GEOLOGY AND PRODUCTION OF MIDDLE TERTIARY...

GEOLOGY AND PRODUCTION OFMIDDLE TERTIARY

MINERAL DISTRICTS IN ARIZONA

BY: JOHN W. WELTY

JON E. SPENCER

GEORGE B. ALLEN

STEPHEN J. REYNOLDS

RI CHARD A. TRAPP

Arizona Bureau of Geologyand Mineral Technology845 N. Park Ave.Tucson, AZ

JANUARY 31, 1985

ARIZONA BUREAU OF GEOLOGY AND MINERAL TECHNOLOGY OPEN-FILE REPORT

85-1

This repo;t is prel!minary and has not been edited orr~vi2'i,'~d fJ( c::r.(Yi;1:ty \':i;h ;\;iz();"a Bureau of GGo!ogy

TABLE OF CONTENTS

pageIntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1

Table 1 - Geologic Descriptions of Mid-Tertiary MineralDistricts 4

Cochise County 4Gila County 7Graham County . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . 7Greenlee County . . . . . . . . . . . . . . . . . . . . . . 9La Paz County 10Maricopa County . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Mohave County 25Pima County ". . . . . . . . . . . . . . . . . . . . . . .. 33Pinal County . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 35Santa Cruz County . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 42Yavapai County 43Yuma County 53

Table 2 - Mid-Tertiary Mineral Districts by LithotectonicAssociation 57

Table 3 - Present Value of Production from Mid-TertiaryMineral Districts 62

Table 4 - Grades of Mid-Tertiary Mineral Districts 69

Table 5 - Grades of Ore by Lithotectonic Association 74

References 75

FIGURES

Figure 1 - Mid-Tertiary Mineral Districts in Arizona 3

Figure 2 - Volcano-Plutonic Associated Mineral Depositsin Arizona 59

Figure 3 - Microdiorite-Dike Associated Mineral Districtsin Arizona 60

Figure 4 - Detachment-Fault Associated Mineral Districtsin Arizona 61

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GEOLOGY AND PRODUCTION OF MIDDLE TERTIARY MINERAL DISTRICTS IN ARIZONA

INTRODUCTION

Areas of known metallic mineralization in Arizona, with recorded production,have been divided into 453 mineral districts, nearly 180 of which are known orsuspected to be mid-Tertiary in age (Keith and others, 1983a,b). This reportbriefly describes the geology of mid-Tertiary mineral districts in Arizona thatwere considered by Keith and others (1983a,b) to be mid-Tertiary, and examinesthe basis of age determinations for each of them. This report is preliminaryin nature, and Bureau-directed mapping and research continues in order toclarify the nature of mid-Tertiary metallogenesis.

Table 1 consists of summaries, based largely upon a review of the publishedliterature, of the geology of mid-Tertiary mineral districts of Arizona. Onlymineral districts with greater than 100 tons recorded production are includedin the compilation. Following each mineral district name is a list of themetals produced, in order of decreasing value at the time of production. Abrief description of the geology of each mineral district is provided andsucceeded by a discussion of the data constraining the age of each district.Many of the districts designated as mid-Tertiary by Keith and others (1983a,b)are thought by us to be older, but are included for completeness. Theessential references for each mineral district are also provided. Thereferences are cited by number and listed alphabetically and numerically at theend of this report. Keith and others (1983b) provide a comprehensive list ofreferences for all metallic mineral districts in the Basin and Range Provinceof Arizona. Many of these references are of limited value; therefore, we listonly those most useful in compiling the basic geologic and geochronologicinformation. Figure 1 is a map showing all the mineral districts in Arizona ofpresumed middle Tertiary age. We have included districts of problematic age onthe figure for completeness.

Table 2 is a list of mineral districts divided into lithotectonicassociations. Our review suggests that most of the mid-Tertiary mineraldistricts may be separated into four groups; these include mineralizationrelated to 1) volcano-plutonic complexes, 2) microdiorite dikes, 3) regionaldetachment faults, and 4) stratabound occurrences (see also Spencer and others,in press). The mineral districts in table 2 are listed in two categories,those mineral districts that are known to be or are probably associated withthe listed lithotectonic element, and those thought to be possibly related tothat lithotectonic element. The differences between known and possibleassociations are based on confidence in the data and on the amount of dataavailable. The geologic setting of many of these mineral districts is stillpoorly known and the available published literature'is often sparse. Figures2, 3, and 4 show the mineral districts thought to be related tovolcano-plutonic complexes, microdiorite dikes, and detachment faults,respectively.

Table 3 lists the present value of production from Arizona's middle Tertiarymineral districts. The Engineering and Mining Journal average 1983 price isused to calculate the present value figures. Copper, gold, silver, molybdenum,and uranium prices have experienced a steady and sometimes sharp decline sincethe time of this compilation, while the other metal prices have experiencedmodest gains in value. The decline in precious metal prices (nearly 30% and

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50% for gold and silver respectively) result in inflated total value figureswhen compared to the current market place (as of January, 1985). The moststriking result of this compilation is that the recorded gold and silverproduction accounts for 84% of the total present value of metals produced frommiddle Tertiary mineral districts, hence the current interest by explorationcompanies in this metallogenic epoch.

Table 4 lists the grade of Cu, Pb, Zn, Mo, Ag, and Au ore produced frommid-Tertiary mineral districts. The table does not include grades for Mn, U,V, and W production because such information is not consistently available.Only those mineral districts with total recorded production in excess of 100tons are listed. The data are complied from u.s. Bureau of Mines minestatistics and are current to 1981.

The lithotectonic associations of table 2 and the grades listed in table 4are merged to create table 5, which shows the average and weighted grade foreach lithotectonic association. The average grades are arithmetic means of theindividual district grades, and hence subject to bias by an anomalously high orlow value. Weighted grades are calculated by summing the total production foreach metal in ounces or pounds and dividing by the total ore produced for eachlithotectonic association. The grades are calculated using only the known orprobable lithotectonic associations.

Each lithotectonic group of districts is weakly characterized by a distinctset of grades, the statistical significance of which is currently underinvestigation. The volcano-plutonic complexes are characterized by the highestlead and silver values with correspondingly lower copper values. Themicrodiorite-related mineralization is highest in copper and gold, but low inlead and zinc. Detachment-fault-related mineralization is high in copper andlead values. The most impressive result of this analysis is that all threelithotectonic associations have average gold grades that could be profitablyexploited under current market conditions.

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'-BLACK DIAMOND Mid-Tertiary Mineral Districts

Arrzona

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Figure I

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TABLE 1. GEOLOGIC DESCRIPTIONS OF MID-TERTIARY MINERAL DISTRICTS

COCHISE COUNTY

DISTRICT: APACHE PASS

PRODUCTION: Au, Pb, Ag

GEOLOGIC SETTING: The Apache Pass District is located within a thick sequence ofwest-northwest-striking, southwest-dipping Paleozoic and Cretaceous sediments with athick rhyolite and andesite sequence overlapping on the north. The orebodies areveins and replacement deposits. Minor barite and molybdenite occur in the district.

AGE: The date of Apache Pass mineralization is uncertain. Karl Tsuji (pers. comm.,1984) states the ore precedes the 34 m.y.B.P. old "Turkey Track" andesite. A possibleperiod of mineralization, therefore, is an extensive 55.9 m.y.B.P. (Laramide) plutonicevent.

REFERENCES: #18, #60, #64, #65, #100, #161, #185, #194

DISTRICT: CALIFORNIA

PRODUCTION: Pb, Zn, Ag

GEOLOGIC SETTING: The California District is underlain by a structurally complexsequence of Paleozoic and Cretaceous sediments that are capped in the center of thedistrict by late Cretaceous andesites. West-northwest-striking thrust faults andnorth-northeast-striking normal faults are the dominant structures. Pipes, shoots,lenses, pockets, and chimneys are characteristic orebody morphologies. Galena,sphalerite, chalcopyrite, arsenopyrite, pyrite, cerussite, anglesite, wulfenite,scheelite, chrysocolla, azurite, malachite, native Cu, native Au, and native Ag areore minerals. Gangue minerals include psilomelane, pyrolusite, garnet, epidote,chlorite, calcite, clinozoisite, quartz, wollastonite, gypsum, tremolite, andlimonite. Silicification is extensive.

AGE: ABGMT file data associates mineralization in the California district with theJhus Canyon pluton which yielded a 30 m.y.B.P. K-Ar biotite age (Shafiquallah andothers, 1978). ABGMT file data states that the 28 m.y.-old Chiricahua volcanicsoverlie the mineralization.

REFERENCES: #18, #100, #185

DISTRICT: MIDDLE PASS

PRODUCTION: Zn, Cu, Ag, Pb, Au, Mo

GEOLOGIC SETTING: The Middle Pass district lies in the complexly faulted Paleozoic

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and Cretaceous sediments of the Dragoon Mountains. Many of the north- andnorthwest-trending contacts are reverse or thrust faults. Extensive poorlymineralized outcrop of the 24 m.y.-old Stronghold Granite separates thewell-mineralized northern and southern portions of the district. Northwest-trendingrhyolite dikes are locally abundant. Another intrusive, possibly related to the 185m.y. Gleeson quartz monzonite, crops out at a few widely spaced localities in thesouthern end of the district. The orebodies are skarns, mantos, and chimneys.

AGE: The general association of ore deposits with the extensively-outcroppingStronghold quartz monzonite is suggestive of a genetic relationship. The 24 m.y.-oldage of the quartz monzonite is therefore suspected to be the age of mineralization.

REFERENCES: #18, #58, #59, #61, #76, #100, #126, #185

DISTRICT: PEARCE

1 PRODUCTION: Ag, Au, Cu, Pb

GEOLOGIC SETTING: The mineralization at Pearce is almost exclusively in the PearceVolcanics which include andesite flows, quartz latite, rhyolite ash flows, tuffs, andepiclastic volcanics. The veins are along major normal faults and in subverticalsheeted zones. Native silver, acanthite, cerargyrite, embolite, and native gold areore minerals. Quartz, calcite, and adularia are gangue. Potassic alteration ispervasive.

AGE: ABGMT filemineralization.nearby volcanismhowever, must bealteration.

data gives a 28-30 m.y. K-Ar biotite age as the time ofThese volcanics are almost certainly mid-Tertiary the same age asin the Chiricahua Mountains. The reported radiometric determination,viewed with caution as the district has undergone extensive potassic

REFERENCES: #93, #100

DISTRICT: RUCKER CANYON

PRODUCTION: Ag, Au

GEOLOGIC SETTING: The Rucker Canyon properties consist of vein mineralization in theMural Limestone of the Cretaceous Bisbee Group. The outcrops in Rucker Canyon arecontrolled by an east-west-trending fault that exposes the Bisbee Group beneath anuppermost Cretaceous andesite and a thick Oligocene silicic-tuff sequence.

AGE: Intrusive activity associated with either the latest Cretaceous andesite or thethick Oligocene volcanics is the probable agent of mineralization. The geochemicalsignature is similar to that of the California mineral district of known mid-Tertiaryage, therefore a mid-Tertiary age seems likely.


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DISTRICT: SWISSHELM

PRODUCTION: Pb, Ag, Au, Zn, Cu, Mo

GEOLOGIC SETTING: The Swisshelm district is on the flank of a major NNW-trending foldof Paleozoic limestones. The anticline is cored by the Swisshelm diorite porphyry.North-northwest-trending thrust faults are a pervasive structural element in thedistrict. The orebodies are dominantly lead replacements with recoverable copper,silver, and gold. Skarns are present in the Pennsylvanian Naco Group and are localizedat the intersection of thrust faults and a variably trending fracture system.

AGE: Shafiquallah and others (1978) reports K-Ar biotite ages of 31 and 34 m.y.B.P.for the Swisshelm stock which intrudes the NNW-trending anticline. This stock ispresumed to be responsible for mineralization.

REFERENCES: #18, #58, #72, #100

DISTRICT: TEVISTON

.~ PRODU CTION: Au, Ag, Pb, CuJ,

GEOLOGIC SETTING: The mines of the Teviston district are small and consist primarilyof base-metal oxides, carbonates, and minor sulfides in irregular quartz veins cuttingPrecambrian Pinal Schist. Precious metal values are erratic but present. Richter andLawrence (1983) map Tertiary felsic flows and pyroclastic deposits, and granitic plugsand dikes close to the Teviston district. .

AGE: Keith and others (1983a,b) ascribe a mid-Tertiary age for this district byvirtue of the district's genetic relationship to a 35-40 m.y.-old dike swarm. The ageof the dike swarm cannot be verified, although it is mapped as Tertiary by Richter andLawrence (1983). This district is very similar to the Apache Pass mineral district,where we have proposed a Laramide(?) age. The age of the Teviston district istherefore problematic.


DISTRICT: YELLOWSTONE

PRODUCTION: Au, Ag, Pb, Cu

GEOLOGIC SETTING: The Yellowstone district is underlain by Precambrian granitoidswith minor klippen of Paleozoic limestones and shales. The Johnny Lyon Hills displayextensive low-angle faulting of mid-Tertiary age (Dickinson, 1984). Two types ofmineralization are evident. In brown carbonate host rocks, veins of variable widthcontain malachite, chrysocolla, and chalcocite, with opaline quartz, boxwork limonite,and calcite as gangue. In the Precambrian Johnny Lyon granodiorite, mineralization issparse and in short veins. Chalcopyrite, malachite, chalcocite, pyrite, trace galena,and limonite occur in massive milky opaline-quartz veins, in vuggy veins, and openfractures. The Yellowstone district mineralization may be related to mid-Tertiarydetachment faulting.

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AGE: Cooper and Silver (1964) describe low-angle faults that cut the Precambriangranites and state that mineralization in these granites cuts low-angle faults;therefore, the bulk of the mineralization is middle Tertiary. Cooper and Silver(1964) also acknowledge some Precambrian mineralization in the granite.

REFERENCES: #18, #38, #50, #100

GILA COUNTY

DISTRICT: Ramsdell

PRODUCTION: Mn

GEOLOGIC SETTING: Psilomelane and pyrolusite occur in a quartzose gangue formingstringers and small lenticular pods along a fissure in coarse-grained quartz diorite.These high-grade lenses and podiform masses are surrounded by a network ofmanganiferous seams and veinlets filling minor fractures of the host quartz diorite.

AGE: Undated. Proximity to Superior ash-flow tuff and by analogy with other districtsweakly suggestive of mid-Tertiary age.

REFERENCES: #70, #121, #199

DISTRICT: SUNSET

t PRODU CTlON : Mn~.

GEOLOGIC SETTING: Manganese minerals occur in shattered Precambian Dripping Spring(?)quartzite along a shear zone striking N70W and dipping 65 NE. Seams, veinlets, andvarious sized irregular masses of psilomelane, pyrolusite and wad. Silica and ironoxides are the dominant gangue minerals.

AGE: Undated; NW strike suggests a mid-Tertiary age.

REFERENCES: 1170

1 GRAHAM COUNTY

DISTRICT: ARAVAIPA

PRODUCTION: Zn, Pb, Cu, Ag, Au, Mo

GEOLOGIC SETTING: The Aravaipa District is lithologically varied with moderatelycomplex structure. Pinal schist, Precambrian granite, Paleozoic sedimentary rocks,Cretaceous sedimentary and volcanic rocks, and extensive middle-Tertiary intrusivesand volcanics are the most prevalent rocks. Ore bodies are located along anorth-northeast, high-angle, normal-fault set and a second set of east-trending,sinuous, low-angle faults. Ore bodies are veins and less important replacements.

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Middle Tertiary rhyolite dikes are commonly associated with ore. Galena andsphalerite dominate with lesser chalcopyrite. Quartz, chalcedony, amethyst,specularite, and fluorite are gangue. Silicification is pervasive.

AGE: The association of ore with rhyolite dikes presumably related to the 25 m.y.-oldSanta Teresa granite indicates a middle tertiary age.

REFERENCES: #40, #49, #150, #159, #170, #171, #172

DISTRICT: BLACK HAWK

PRODUCTION: Mn

GEOLOGIC SETTING: Manganese minerals occur in narrow veins and along a broad fracturezone cutting 1.4 b.y.-old Precambrian biotite quartz monzonite. The veins are largelyfilled with quartz and contain small local bunches of manganese oxides, which includepsilomelane and pyrolusite. Quartz and calcite comprise an abundant gangue.

AGE: Veins are in lower-plate rocks of the Eagle Pass detachment fault. The faultcuts middle Tertiary rocks; therefore mineralization is middle Tertiary or younger. Amiddle Tertiary age is favored.


DISTRICT: RATTLESNAKE

PRODUCTION: Ag, Au

GEOLOGIC SETTING: The Rattlesnake District is in the southern Galiuro Mountains, anarea underlain by middle to late Tertiary volcanics. The deposits are mostly hosted inandesitic to rhyolitic volcanic fragmentals and breccia. The district is centered on

a NNW-trending syncline. Native gold, hematite, pyrite, chrysocolla, and quartz arethe ore minerals. The orebodies are associated with andesite porphyry dikes.

AGE: A 25-20 m.y.B.P. old date is given by analogy to dated andesite dikes elsewherein the Galiuro Mountains.

REFERENCES: #40, #41, #42, #90, #194

DISTRICT: SAN CARLOS

PRODUCTION: Mn

GEOLOGIC SETTING: Manganese minerals occur in seams, stringers, and small irregularbunches distributed sporadically along northwest-trending fractures and brecciatedzones in volcanic rocks. The ore minerals are chiefly psilomelane, pyrolusite, andwad. Calcite and iron oxides are the principal gangue minerals. The largermineralized bunches, seldom exceeding one foot in greatest dimension, are composedlargely of small nodules and stringers of ore mixed with calcite and brecciated

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wallrock fragments.

AGE: Bromfield and Schride (1956) map the volcanic rocks hosting the San Carlosdistrict as older Tertiary volcanic rocks. This volcanic package is a succession ofrhyolitic, andesitic, and basaltic flows, breccias, and tuffs. The volcanics of theSan Carlos district are almost certainly of mid-Tertiary age; it seems probable themanganese deposits are of mid-Tertiary age also.

REFERENCES: #31, #42, #70

DISTRICT: STANLEY

PRODUCTION: Pb, Cu, Ag, Au, Zn\

I GEOLOGIC SETTING: The Stanley District encompasses a diverse series of rocks. Thesouthwest portion of the district has NIOW- to N40W-striking Paleozoic sedimentaryrocks with moderate SW dips. A block of Precambrian granite crops out to thenortheast. A large Tertiary quartz monzonite pluton and Oligocene volcanics arepresent in the periphery of the district. The northwest-trending Deer Creek synclinedominates the southwestern part of the district. Although Cretaceous sediments andvolcanics are infrequent hosts, Paleozoic limestone is the prevailing host to veinsand replacements. A variety of volcanics and dikes are associated with ore andinclude quartz porphyry, andesite, and rhyolite volcanics, and diabase dikes.Chalcopyrite, sphalerite, bornite, azurite, pyrolusite, and stibnite are reported oreminerals. Quartz, calcite and pyrite are reported gangue with lesser fluorite,barite, specularite, johannsenite, garnet, and magnetite.

AGE: The ore is presumed to be contemporaneous with the extensive 25 m.y.-old SantaTeresa Granite.


GREENLEE COUNTY

DISTRICT: ASH PEAK

PRODUCTION: Ag, Au, Cu, Pb, Zn

GEOLOGIC SETTING: The enormous amount of silver produced from the Ash Peak districtcame from veins and replacements hosted by a thick middle-Tertiary volcanic andvolcaniclastic sequence. The section attains a thickness of up to 1000 mand isintruded by northwest-trending dikes that may have been controlled by N45W-trendingnormal faults. Plugs of diabase locally intrude the section as well. Precious metalmineralization is restricted to the Miocene rhyolite domes, flows, and pyroclastics ofthe Ash Peak-Rhyolite Peak flow dome-cone complex (Richter and others, 1983) andcharacteristically has argentite, rhodochrosite, and pyrite, with banded chalcedonicquartz. Psilomelane and lesser pyrolusite with calcite hosted by basalt constitutes asecond, separate ore type. The common northerly strike to these manganese orebodiesin contrast to the exclusive N45W trend of the precious metal mineralization supports

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two distinct phases of mineralization.

AGE: Richter and others (1983) assign a 22 to 23 m.y. age for the Ash Peak-RhyolitePeak eruptive center which contains the N45W-trending vein of the Ash Peak Mine.

REFERENCES: #70, #114, #144, #154, #155

DISTRICT: GILA HOT SPRINGS

PRODUCTION: Mn

GEOLOGIC SETTING: Manganese occurs at the Gila Hot Springs district in pods andlenses in the Bonita Creek Conglomerate. The ore cuts bedding in the conglomerate at ahigh angle. Wad, pyrolusite, and barite are ore minerals. Black and white calciteare prevalent gangue minerals.

AGE: The host Bonita Creek Conglomerate is locally interbedded with pyroclasticair-fall and ash-flow deposits of the Tolgate Wash eruptive center and the upperandesite flows of the Guthrie Peak-Turtle Mountain Formation. Richter and others(1983) state that these volcanics were erupted from 19 to 24 m.y. ago, hence themanganese mineralization is no older than about 20 m.y.


DISTRICT: TWIN PEAKS

PRODUCTION: Ag, Au, Cu, Pb

GEOLOGIC SETTING: The Twin Peaks district lies exclusively within a thick pile ofsilicic and intermediate volcanics ranging in age from Oligocene to mid-Miocene. Awhite, massive, flow-banded rhyolite of middle oligocene age is the dominant rocktype. A set of mid-Oligocene rhyolite dikes trends N45E and another set of Miocenemafic dikes trends N50W to N70W. The Twin Peaks Mine proper is a north-trendingmanganese vein in New Mexico. The only documented Arizona production from the TwinPeaks District is at a minor fluorite-manganese property. Ratte and Hedlund (1981)show areas of extensive alteration and veining in adjacent New Mexico, suggesting thatthe majority of base and precious metal production may have come from New Mexico.

AGE: A Oligocene to middle Miocene age of mineralization is reasonable, in view ofthe predominance of a middle Oligocene rhyolite host. By analogy to the nearby andsimilar Ash Peak District, a 22 m.y.B.P. is possible.

REFERENCES: #70, #86, #114, #144

LA PAZ COUNTY

DISTRICT: ABC

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PRODUCTION: Mn

GEOLOGIC SETTING: Psilomelane occurs in brecciated wallrocks andnorth-south-striking, steeply west-dipping, parallel, shear veins cutting Tertiaryandesitic volcanics.

AGE: The veins cut a volcanic package informally known as the Trigo MountainVolcanics. These volcanic rocks are considered to be mid-Tertiary in age based oncorrelation with similar dated rocks in the Castle Dome Mountains, and similar rocksthroughout southwestern Arizona.


DISTRICT: ALAMO

PRODUCTION: Cu, Au, Pb, Ag

GEOLOGIC SETTING: Copper carbonates, silicates, and minor sulfides at depth, withlocal lead carbonate in fissure veins. Strong silicification with minor epidote,fluorite and selenite in association with the veins in and near a low-angle normalfault zone. The veins are found in altered mylonitic schist and gneiss, and arelocated near dikes and intrusive plugs of quartz monzonite.

AGE: These deposits are inferred to be related to mid-Tertiary movement on theWhipple-Buckskin-Rawhide Mountains detachment fault. However, the presence of sulfidesand the possible association of mineralization with dikes and intrusive plugs suggeststhat at least some of the mineralization might not be related to detachment faulting.

REFERENCES: #47, #103, #137

DISTRICT: ARTILLERY

PRODUCTION: Mn

GEOLOGIC SETTING: Stratabound manganese oxides in the Artillery district occur in theearly to middle Miocene Chapin Wash Formation in western Arizona. Manganese oxidesare locally present in the clay cement of every type of sedimentary rock in the ChapinWash Formation, including siltstone, sandstone, conglomerate and tuff. Supergeneenrichment of some of the ore has raised the grade of the ore from 3-4 percent to 6-7percent Mn.

AGE: Volcanic rocks in the Chapin Wash Formation have yielded early to middle MioceneK-Ar ages.

REFERENCES: #63, #117, #125, #130, #136, #168, #174

DISTRICT: BOUSE

PRODUCTION: Au, Cu, Ag, Mn

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GEOLOGIC SETTING: Veins of barite and of pyrolusite, psilomelane, and manganitewith calcite occur in brecciated middle Tertiary volcanic wallrocks (Keith, 1978) •

. AGE: Most of the deposits are hosted by middle Tertiary volcanic rocks, and thereforeare middle Tertiary or younger. A middle Tertiary age is favored since this was atime of widespread magmatism and faulting.

REFERENCES: #103, #106, #107, #174

DISTRICT: CIENEGA

PRODUCTION: Cu, Au, Ag

GEOLOGIC SETTING: Small, discontinuous, replacement bodies containing coppersilicates, carbonates, and oxides, occur with iron oxides and spotty gold values. Thedeposits are associated with faults, fractures, and shear zones along and above theWhipple-Buckskin-Rawhide detachment fault system. Blocks.of partially metamorphosedPaleozoic and Mesozoic limestones, shale, quartzites, and underlying Precambrianmetamorphic rocks host the orebodies.

AGE: These deposits are located along structures thought to be related to theWhipple-Buckskin-Rawhide detachment fault system of mid-Tertiary age. A middleTertiary or younger age is indicated, and a middle Tertiary age is probable.

REFERENCES: #21, #47, #103

DISTRICT: CINNABAR

PRODUCTION: Hg, Cu, Au, Ag

GEOLOGIC SETTING: Spotty disseminations of cinnabar occur with minor metacinnabar,malachite, chrysocolla, gold, and silver. Gouge, brecciated quartz, calcite, andsiderite comprise the gangue. Ore and gangue minerals occur in strongly iron-stainedfaults and fissures cutting Mesozoic schists.

AGE:. Age is Mesozoic or Cenozoic. Keith and others (1983a,b) assign a middleTertiary(?) age for reasons that are not given in their paper.

REFERENCES: #21, #103, #106, #107

DISTRICT: CLARA

PRODUCTION: Cu, Ag, Au

GEOLOGIC SETTING: Copper silicates and carbonates occur with minor chalcocite andsparse leaf gold. Gangue consists of abundant calcite, quartz, gypsum and hematite.Mineralization consists of fracture fillings along and near the Buckskin-Rawhidedetachment fault. This fault places middle Tertiary conglomerates over myloniticgneiss.

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AGE:. Mineralization is related to the middle Tertiary Buckskin-Rawhide Mountainsdetachment fault, and therefore is mid-Tertiary in age.

REFERENCES: #21, #103, #174

DISTRICT: CUNNINGHAM PASS

PRODUCTION: Cu, Au, Ag, Pb

GEOLOGIC SETTING: Spotty, but typically high-grade pockets of copper-gold-silvermineralization occur with quartz, iron oxides, siderite, calcite, and barite inlenses. The lenses of mineralization are found within or along contacts withnorthwest-trending microdiorite dikes that have intruded Mesozoic and Cenozoicmetamorphic and granitic rocks.

AGE: Microdiorite dikes in the Harquahala Mountains yielded a hornblende K-Ar age of28.6 m.y.B.P., and a biotite K-Ar age of 22.1 m.y.B.P., indicating mid-Tertiary agefor the ore deposits.

REFERENCES: #21, #103, #148

DISTRICT: ELLSWORTH


GEOLOGIC SETTING: Numerous, irregular, splitting and lensing veins of quartz,siderite, calcite, and brecciated wallrock containing spotty, oxidized and sulfidecopper mineralization, occur with gold and silver metallization. Some veins areassociated with microdiorite or rhyolite(?) dikes that intrude Mesozoicmetasedimentary and metavolcanic rocks and, locally, Paleozoic metasedimentary andPrecambian crystalline rocks.

AGE: Mid-Tertiary age is probable if mineralization is associated with microdioritedikes, since similar dikes of mid-Tertiary age are known in the nearby HarquahalaMountains.

j REFERENCES: 1121,1/103,11174

DISTRICT: FOOLS FOLLY

PRODUCTION: Mn

GEOLOGIC SETTING: Pyrolusite is found along steeply-dipping, east-trending fracturezones in volcanic rocks. The fractures extend almost continuously for 200 metersalong strike. Gangue consists mostly of unreplaced fragments of the host volcanicrocks.

AGE: Host volcanic rocks are probably mid-Tertiary in age. If so, mineralization ismid-Tertiary or younger.

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REFERENCES: 1t69

1 DISTRICT: HARCUVAR


GEOLOGIC SETTING: Spotty copper sulfides and secondary copper mineralization inirregular quartz-siderite veins or associated with microdiorite or diorite dikes.Some of the veins and middle Tertiary microdiorite dikes are in northwest-strikingfissure zones. Rost rocks are Mesozoic granite and metamorphic rocks.

AGE: The microdiorite dikes are almost certainly middle Tertiary in age based oncorrelation with dated dikes in the Rarquahala Mountains. Associated mineralization isprobably middle Tertiary in age.

l REFERENCES: 1121, 11103t

DISTRICT: HARQUAHALA

PRODUCTION: Au, Cu, Ag, Pb

GEOLOGIC SETTING: The Rarquahala district is composed of pockety, irregular, andlensing deposits along veins and as replacements. The ores are characteristicallygold and silver rich with minor contributions from oxides of base metals. Ore shootsare associated with quartz, calcite and abundant iron oxides. The wallrocks includePrecambrian granitic and gneissic rocks, Paleozoic sediments, and undated microdioritedikes. The wallrocks are locally silicified, sericitized, and brecciated. Veins andreplacements are near northwest to north-northwest-striking faults and microdioritedikes. Although the dikes are thought to be genetically related to the oreoccurrences, mineralization is, at least in part, spatially associated with Mesozoicthrust faults.

AGE: The spatial association of mineralization with middle Tertiary microdioritedikes indicates that many of the deposits are middle Tertiary in age. Furtherdetailed study, including geoc~ronologic studies, are needed to accurately determine

i the age and nature of all of the deposits.i

REFERENCES: 1115, 1121, 1t103, 1t105

DISTRICT: LA CROLLA

PRODUCTION: Au, Cu, Ag

GEOLOGIC SETTING: Spotty and irregular copper, gold, and silver mineralization asdisseminations and veins in or near northwest- to west-northwest-striking microdioritedikes. The veins are quartz-rich and occur along faults in Mesozoic metasedimentaryand metavolcanic rocks. Crowl (1979) describes malachite in noses of folds inMesozoic McCoy Mountains Formation at the Copper Bottom mine.

14

AGE: The northwest-striking microdiorite dikes are almost certainly mid-Tertiarybased on dike orientation and on lithologic similarity to dated dikes in other ranges.

REFERENCES: #21, #43, #103

DISTRICT: LA PAZ


GEOLOGIC SETTING: Spotty gold, silver, and gold-bearing pyrite with minor copper andlead mineralization in lensing massive quartz and iron-oxide-rich veins. The veinsare in shear zones cutting Mesozoic metavolcanic rocks. A nearby rhyolitic plug ofunknown age may be related to the mineralization. Crowl (1979) describes chrysocollain fractures in metavolcanic rocks with associated quartz-sericite-pyrite hydrothermalalteration of host metavolcanics.

, AGE: There is insufficient data to reliably constrain the age of this district,although it is almost certainly Laramide or mid-Tertiary. A probable mid-Tertiary agefor the rhyolite plug, and a possible relationship between mineralization and therhyolite plug, suggest a mid-Tertiary age of mineral~zation.


DISTRICT: LINCOLN RANCH

PRODUCTION: Mn

GEOLOGIC SETTING: Manganese oxides coating grains, clasts, and fracture surfaces insheared and faulted Tertiary sandstone and conglomerate. Some mineralization predateslatest movement on the Buckskin detachment fault.

AGE: Middle Tertiary age is indicated by the association with middle Tertiary rocks.


1 DISTRICT: LITTLE HARQUAHALA


GEOLOGIC SETTING: Rich, pockety shoots of gold with minor silver in a gangue of ironoxides, shattered quartz, and gypsum. The ore shoots are found in shear zones cuttingPrecambrian granites, shattered Cambrian quartzites, and strongly folded and faultedPaleozoic sedimentary rocks, and are locally near microdiorite dikes. The richerdeposits occur in the shattered quartzites.

AGE: Apparent association with mid-Tertiary microdiorite dikes in some parts of thedistrict (Keith and others, 1983a,b) is suggestive of a middle Tertiary age ofmineralization.

15

REFERENCES: #21 t #103

DISTRICT: MAMMON

PRODUCTION: CUt AUt Ag

GEOLOGIC SETTING: Hematite replacement bodies and breccia fillings with spottYtnarrow t and lensing oxidized copper mineralization with minor gold and silver t alongshear zones between metamorphics and granitic intrusives t and along schistosity in theschists.

AGE: Mineralization is almost certainly the result of intermittent hydrothermalactivity associated with low-angle normal faulting in the Whipple-Buckskin-Rawhide

j Mountains. The faulting t and probably also the mineralization, are mid-Tertiary age.

REFERENCES: #21 t #47, #103 t #189

DISTRICT: METATE

PRODUCTION: Mn

GEOLOGIC SETTING: High-grade (~40% Mn) zones of soft pyrolusite t psilomelane t andmanganite t with very little gangue t occur as irregular replacements along a minor foldin limestone. Ore bodies are discontinuous along strike and typically less than ameter thick and no longer than 4 meters. The manganese-rich replacements appear to belocalized in a westerly-dipping fissure zone cutting the northern limb of a fold inthe limestone. Reconnaissance mapping indicates that most of the district isunderlain by Mesozoic metavolcanic rocks.

AGE: Host limestone is of unknown age but possibly Mesozoic age t suggesting aMesozoic or Tertiary age for mineralization. A mid-Tertiary age is suggested bysimilarity to dated Mn deposits in adjacent areas.

REFERENCES: #69 t #103 t #174

;

! DISTRICT: MIDDLE CAMP~

PRODUCTION: Pb t AUt Ag t Cu

GEOLOGIC SETTING: Spotty gold t silver t lead t copper t and zinc mineralization inquartz veins t stringers t and in replacement deposits along fractures in Mesozoicmetamorphic and granitic rocks. The veins are locally northwest-striking and thoughtto be associated with the Diablo quartz monzonite. Chalcopyrite is associated withgold-bearing veins at the Marquitta and Goodman mines (Crowl t 1979).

AGE: The veins have the characteristic mid-Tertiary strike t but may be related to theDiablo quartz monzonite of probable Mesozoic age.


16

DISTRICT: MIDWAY


GEOLOGIC SETTING: Spotty, oxidized copper mineralization with minorgold. Hematite, quartz, barite, and fluorite are present as gangue.fractures cutting Mesozoic sediments and Precambrian gneisses, or aslimestones.

sulfides andThe ore is along

replacements in

AGE: The mineralogy and style of mineralization suggest metallization related tomovement on the Buckskin-Rawhide detachment fault of mid-Tertiary age.


DISTRICT: MOON MOUNTAINS

PRODUCTION: Au, Ag

GEOLOGIC SETTING:copper sulfides inmetamorphic rocks.

Spotty gold and silver mineralization with minor, partly oxidizedlensing quartz veins and disseminations cutting Mesozoic(?)

AGE: The Moon Mountains detachment fault of mid-Tertiary age is exposed at the northend of the east ridge of the Moon Mountains. Mineralization at this locality isclearly related to the fault and hence is mid-Tertiary. Little geologic informationis available from other parts of the Moon Mountains although a mid-Tertiary age hasbeen suggested (Keith and others, 1983a,b) for other areas of mineralization in thedistrict.

REFERENCES: #103

DISTRICT: NEW WATER

PRODUCTION: Ag, Pb, Cu, Au

GEOLOGIC SETTING: Spotty silver, lead, and copper oxide mineralization with limonitei along joints, fractures, and small high-grade chimneys in epidotized porphyritic

andesite and volcanic agglomerate.

AGE: The host volcanic rocks are mid-Tertiary, hence mineralization is mid-Tertiaryor younger. Mineralization is probably a consequence of widespread mid-Tertiarymagmatism, and therefore is probably mid-Tertiary in age.


DISTRICT: NORTHERN PLOMOSA

PRODUCTION: Au, cu, Ag, Pb

17

GEOLOGIC SETTING: Spotty, fine-grained gold with oxidized copper, silver and leadmineralization in narrow, lensing and irregular veins. Ore is found along faults, andat intersections between cross-fractures and the contact of shale, limestone andwelded tuff with Precambrian gneiss and schist. Veins also cut Miocene volcanicrocks. Brecciation of the wallrocks is intense, with local replacement of thewallrock by manganese and iron oxides.

AGE: The veins are hosted in part by middle Tertiary volcanic rocks, so aremid-Tertiary or younger in age. Most of the district is in the upper plate of thePlomosa detachment fault, and mineralization could be related to faulting. If so, thedeposits are mid-Tertiary in age.

REFERENCES: #21, #63, #106, #107

DISTRICT: PLANET

1 PRODUCTION: Cu, Au, Ag

GEOLOGIC SETTING: Copper carbonates and silicates, with minor copper sulfides andpyrite at depth, occur in disseminations, veinlets, and irregular, lensing,replacement bodies of specular hematite. Wallrocks are brecciated carbonates andshales. Some carbonate masses may have been formed by replacement of preexistingrocks. The orebodies are found along a flat fault zone with gouge, quartz, calciteand feldspar.

AGE: Mineralization is within the Buckskin-Rawhide low-angle detachment fault systemof mid-Tertiary age, and is probably related to faulting. A mid-Tertiary age isstrongly suggested.


DISTRICT: SILVER

PRODUCTION: Ag, Pb, Cu, Zn, Au

GEOLOGIC SETTING: Deeply oxidized argentiferous lead, zinc, and copper mineralizationin a gangue of quartz, calcite, limonite, barite, and fluorite. Ore-bodies arespotty, irregular and lensoidal. Middle Tertiary volcanic and sedimentary rocks hostthe ore shoots along high-angle normal faults.

AGE: Recent work (Pietenpol, 1983) in this district suggests the vein deposits areassociated with high-angle normal faulting and volcanism of the Basin and Rangedisturbance. The age of volcanism, faulting, and mineralization is middle to lateTertiary.

REFERENCES: #21, #136A, #142

DISTRICT: SOUTHERN PLOMOSA

18

}I


GEOLOGIC SETTING: Largely oXidized, spotty copper, gold, and silver mineralizationwith minor lead, in small, irregular, lensing pods. The ore shoots are found in highlydeformed, schistose, silicified, epidotized Paleozoic limestones and Mesozoiccontinental sediments. The quartz-rich mineralized zones are associated withmicrodiorite dikes.

AGE: Microdiorite dikes associated with mineralized zones are almost certainlymid-Tertiary in age based on lithologic similarity to dated dikes in nearby ranges.


DISTRICT: SWANSEA


GEOLOGIC SETTING: Disseminated and veinlet copper oxide mineralization in severallarge, irregular lensing hematite replacement bodies. Chalcopyrite, bornite, andpyrite are found at depth in a gangue of quartz, chlorite, and epidote. Ore bodiesare in a basal section of a folded block of replacement(?) carbonate and schist thatis in low- angle, normal-fault contact with mylonitic gneiss.

AGE: These deposits are the result of hydrothermal activity along the mid-TertiaryBuckskin-Rawhide detachment fault system, and formed during faulting.


DISTRICT: TRIGO MOUNTAINS

PRODUCTION: Pb, Ag, Au, Cu

GEOLOGIC SETTING: Spotty, high-grade, gold-silver mineralization in a gangue of vuggyand banded quartz, iron oxides, ferruginous calcite, and pyrite. Ore bodies arecavity and fracture fillings along shear zones in Tertiary volcanic rocks and inMesozoic(?) and Precambrian basement rocks.

AGE: This district is possibly related to the Trigo Mountain detachment fault systemof mid-Tertiary age. At least some of the mineralization is hosted by mid-Tertiaryvolcanic rocks, and is therefore mid-Tertiary or younger. A mid-Tertiary age isfavored.


MARICOPA COUNTY

DISTRICT: AGUILA

19

PRODUCTION: Mn

GEOLOGIC SETTING: Manganese mineralization occurs in Precambrian metamorphic andgranitic rocks and overlying Tertiary andesites and light-colored tuffs. Themanganese deposits are as prevalent in the basement rocks as in the younger volcanicrocks. Faulting is common in the area, and locally has disrupted the continuity oforebodies. The chief manganese minerals are a mixture of pyrolusite, psilomelane, andmanganite. The gangue is composed largely of calcite, quartz, and unreplacedfragments of the wallrocks. The manganese minerals occur as fissure fillings, asirregular masses, and in networks of smaller seams surrounding brecciated fragments ofcountry rock. Individual deposits range from narrow veins, with small but enrichedore shoots, to wide shears and brecciated zones of lower grade material. The majorityof the veins and mineralized fracture zones strike north and dip steeply to the west.

AGE: Since the ore occurs in mid-Tertiary volcanic rocks, it is mid-Tertiary oryounger. A mid-Tertiary age is favored since this was a time of widespread magmatismand tectonism.

REFERENCES: #69

DISTRICT: BIGHORN


GEOLOGIC SETTING: Precambrian crystalline rocks and Laramide granitic rocksconstitute the bedrock in the Bighorn District. A westward prong of Tertiaryvolcanics extends into the district from the extensive andesites of the centralBighorn Mountains. Precious metal mineralization is restricted to massive,coarse-grained, quartz pods and veins with hematite and limonite in low- to high-angleshears in Precambrian schists and foliated granite. The veins are locally commingledwith felsic dikes. The wall rocks are notably sericitized. The Aguila manganese-baritedistrict lies in the same general area as the native gold mineralization of theBighorn District.

AGE: The age of mineralization is uncertain but a mid-Tertiary age is suggestedbecause mineralization is as~ociated with "basic dike rocks" of the EI Tigre mine(Wilson and others, 1967), and these dikes may be mid-Tertiary microdiorite dikes as

~ in the nearby Harquahala Mountains where they have yielded mid-Tertiary K-Ar dates.Other mineralized areas are associated with northeast-trending rhyolitic dikes, andmay be Laramide.

REFERENCES: #148, #149, #185, #191, #194

DISTRICT: CAVE CREEK


GEOLOGIC SETTING: The Cave Creek District is extensive and encompasses manyorebodies. The district is located at the southern edge of the Yavapai Seriesmassive-sulfide belt. Bedrock consists of a basal tholeiitic to calc-alkaline

20

,,j

metavolcanic sequence with an upper calc-alkaline sequence with a distinct set ofbanded iron formations and tuffaceous sediments. Mineralization at the Grey's Gulchand Phoenix-Maricopa Mines of the district is probably of Precambrian age. Incontrast, the majority of the mines are intimately associated with porphyriticrhyolite and porphyritic diorite-andesite dikes which are probably of Cretaceous orTertiary age. Native gold in quartz is the most commonly cited mineralogy.Vanadinite, molybdenite, galena, malachite, azurite, anglesite and hematite alsooccur.

AGE: The association of mineralization with unfoliated dikes and intrusives indicatesa probable Laramide or mid-Tertiary age.

REFERENCES: #11, #54, #185, #194

DISTRICT: GOLDFIELD

PRODUCTION: Au, Ag

GEOLOGIC SETTING: The Goldfield District is astride a horst block of Precambrian RuinGranite which lies between the late Oligocene-Miocene Goldfield and Superstitionvolcanic fields. The volcanic piles range from basanites to high silica rhyolites incomposition. The ore is dominantly free gold in north and north-northeast-trending,fault-controlled quartz veins. Some orebodies have andesitic volcanics along thefracture zones. Pyrite and limonite are also reported but, notably, no copperminerals are known.

AGE: Sporadic Miocene(?) dikes associated with some orebodies suggest mineralizationis related to the mid-Tertiary volcanics.

REFERENCES: #138, #185, #194

DISTRICT: OSBORNE

PRODUCTION: Pb, Au, Cu, Ag, Zn

GEOLOGIC SETTING: Northeast- to northwest-trending, steeply dipping veins cuttingPrecambrian crystalline and middle Tertiary volcanic rocks characterize the Osbornedistrict. The veins are commonly associated with silicified and brecciated zones inthe volcanic rocks. Galena, chalcopyrite, chalcocite, sphalerite, and pyrite are foundin a gangue of quartz and calcite. The upper levels of the mine workings are oxidizedand marked by the presence of base metal carbonate and oxide minerals.

AGE: Veins cut middle Tertiary volcanic rocks, and therefore are middle Tertiary oryounger. A middle Tertiary age is favored since this was a time of widespreadmagmatic and tectonic activity.

REFERENCES: #15

DISTRICT: PAINTED ROCK

21

· PRODUCTION: Cu, Pb, Ag, Au

GEOLOGIC SETTING: The Painted Rock district lies in the low hills off the northwestflanks of the Painted Rock Mountains. Bedrock in the Painted Rock district consistsof middle Tertiary andesite flows and agglomerates which are intruded by a variety ofdike rocks. South of the district quartz latite porphyry abundantly intrudes theandesite. These rocks are overlain by an approximately 475-meter-thick ash flow tuffwith vitrophyre that forms prominent massive to columnar outcrops. The youngest unitsin the Rowley Mine area are calcite-cemented volcanic gravels which form benches.Mineralization is restricted to a N30W- to N40W-trending fault zone in the andesitethat dips 40 to 50 northeast. The fault lies between two ore types: a quartz vein onthe footwall and a barite vein on the hangingwall. The quartz vein is of fairlyuniform, 2 meter thickness and contains no gouge or breccia. The quartz vein is amassive replacement of the andesite. The barite vein ranges 5 to 10 meters thick andis generally brecciated and deformed (Wilson and Miller, 1974). The inferred hypogenemineralization is barite, quartz, fluorite, galena, pyrite, chalcopyrite, andsphalerite (Wilson and Miller, 1974).

AGE: The mineralization occurs within volcanic rocks of possible mid-Tertiary age,and is therefore mid-Tertiary or younger. A mid-Tertiary age is favored since this wasa time of widespread magmatism.

REFERENCES: #112, #176, #200

DISTRICT: PIKES PEAK

PRODUCTION: Au, Cu, Pb, Ag

GEOLOGIC SETTING: The Pikes Peak district is in Precambrian schist and banded ironformation. Andesitic dikes intrude the sequence and are associated with much of themineralization. The mineralization is in veins and pods and contains notable lead andzinc oxides and sulfides along with native gold, cerargyrite, vanadinite, wulfenite,descloizite, and gangue of hematite, magnetite, pyrolusite, and hausmannite.

AGE: Many ore deposits are associated with andesitic dikes that are almost certainlyof mid-Tertiary or Laramide age.

1 REFERENCES: #15, #185, #198

DISTRICT: RELIEF

PRODUCTION: Au, Ag

GEOLOGIC SETTING: No published description of the general geology of the Reliefdistrict is available. The Wilson and others (1957, 1969) maps show the mines ingranite of Precambrian age and near a Laramide(?) granitoid. Ore is in quartz veinscutting granite and syenite. Free gold, copper carbonates, and free silver are theore minerals.

AGE: Uncertain, but probably Laramide or mid-Tertiary.

22

REFERENCES: #15, #149, #198

DISTRICT: SALT RIVER MOUNTAINS


GEOLOGIC SETTING: The South Mountains (previously referred to as the Salt RiverMountains) contain two terranes; the eastern half of the range is mylonitizedgranodiorite,granite, and alaskite of mid-Tertiary age, and the western half consistsof Precambrian metamorphic and granitic rocks that are mylonitized in the east butgradually less so to the west. The Salt River Mountains mineral district is in quartzveins in the Precambrian terrane and is associated with a north-northwest trendingdike swarm. Mineralization closely followed cessation of mid-Tertiary mylonitization.Native gold is the ore mineral with limonite and hematite gangue. Sericitization is

widespread.

, AGE: The gold deposits of the Salt River Mountains district are of middle Tertiaryage.

REFERENCES: #149, #152, #185, #194

DISTRICT: SAN DOMINGO


GEOLOGIC SETTING: Middle Tertiary(?) veins along faults, possibly within the upperplate of a regional detachment fault system (Keith and others, 1983a,b). A thoroughliterature review did not reveal any substantive geologic descriptions for thisdistrict.

AGE: Keith and others (1983a,b) locate the district partly within mid-Tertiaryvolcanic rocks, indicating a mid-Tertiary or younger age.


1 DISTRICT: SUNRISE~

~

PRODUCTION: Cu, Ag

GEOLOGIC SETTING: Mineralization at the Sunrise Mine occurs along a fault thatstrikes N20E and dips 45NW. Schistose Precambrian metamorphic rocks form the footwalland biotite granite of unknown age forms the hangingwall. A stockwork of lenticularquartz veins occupy a zone 3-6 meters wide along the fault. Fine to coarse grains andflakes of gold occur within brecciated white quartz with abundant limonite andhematite. Native gold, native silver, and copper carbonates are the ore minerals.The wallrocks exhibit sericitization, silicification and carbonatization.

AGE: Probably Laramide or mid-Tertiary.

23

REFERENCES: #15, #149, #151, #198

DISTRICT: VULTURE


GEOLOGIC SETTING: The Vulture vein occurs along a north-northwest striking, northeastdipping fault zone in Precambrian schist. Granite of unkno~~ age hosts some of thedeposits at depth in the Vulture Mine. A granite is associated with the gold-bearingquartz veins. In the oxide zone native gold occurs in milk quartz with occasionalwulfenite. Below the oxidized zone pyrite, galena, sphalerite, and chalcopyrite arefound.

AGE: The nearby presence of a large Laramide plutonic body (the Wickenberg batholith)is suggestive of a Laramide age, but the association of the quartz veins withnorth-northwest-trending a granite porphyry dike is suggestive a mid-Tertiary age.

REFERENCES: #149, #151, #185, #194

DISTRICT: WEBB


GEOLOGIC SETTING: Precambrian schist intruded by granitic plutons of uncertain ageforms the country rock in the Webb district. Mineralization is in veins strikingvariably from NI0E to N35W. Mineralization is also in quartz monzonite dikes. Oreminerals are chrysocolla, malachite, cuprite, bornite, chalcopyrite, and chalcocite.The B & H #6 barite prospect is also within the district and is presumably aconsequence of a separate, later mineralizing event.

AGE: Cheeseman (1974) suggests that copper mineralization in this district is eitherof volcanogenic origin or related to the weak development of a porphyry copper system.The relationship between ore and host rocks is equivocable.

REFERENCES: #36A, #176

DISTRICT: WINIFRED


GEOLOGIC SETTING: Country rocks in the Winifred district include Precambrianmetamorphic rocks (Yavapai Series) and a granitoid of unknown age. The major veinstrikes southeast and consists of coarse, vuggy greyish-white quartz with occasionalcalcite and hematite. Pyrite is also locally present.

AGE: Northwest strike could be indicative of a middle Tertiary age.

REFERENCES: #185, #194, #198

24

MOHAVE COUNTY

DISTRICT: ARTILLERY PEAK

PRODUCTION: Ag, Cu, Au, Pb

GEOLOGIC SETTING: Very little geologic information exists for this district.Available information indicates that ore-minerals including chrysocolla, malachite,chalcocite, and gold and silver are present in veins hosted by Paleozoic limestone andPrecambrian schists. The veins are associated with rhyolite dikes that intrude thelower Artillery Formation.

AGE: K-Ar dates from the Artillery formation give a 21-16 m.y.-old age for this unit.The rhyolite dikes are no older and possibly are considerably younger; a mid-Tertiary

age of mineralization probable, although a late-Tertiary age is possible.

REFERENCES: #117, #136, #167, #168

DISTRICT: BLACK BURRO

PRODUCTION: Mn

GEOLOGIC SETTING: Soft, finely-divided, manganese oxides disseminated through areddish sandstone similar to the Chapin Wash Formation. Parts of the outcrop haveundergone supergene enrichment and are characterized by numerous fractures filled withpsilomelane and pyrolusite.

AGE: The host sediments and ore are probably correlative with the lower MioceneChapin Wash Formation.

REFERENCES: #68, #136, #167, #168

DISTRICT: BLACK DIAMOND

PRODUCTION: Mn

Jt GEOLOGIC SETTING: The Black Diamond deposit occurs in a steeply dipping fault zone

cutting Paleozoic carbonate rocks. The zone is up to 20 meters wide, strikes NE, andis exposed for several hundred feet along strike. The fault zone is composed ofbrecciated fragments of silicified limestone. The manganese minerals, consisting ofwad, pyrolusite, and psilomelane, occur in a complex pattern of fractures surroundingthe brecciated fragments of limestone. Where the fractures are numerous and closelyspaced they may coalesce and form irregular masses of high-grade ore.

AGE: Mesozoic or Cenozoic.


25

DISTRICT: BUCK MOUNTAINS

GEOLOGIC SETTING: Available literature on this district is sketchy and inconclusive.ABGMT file data indicates the Yucca Mine of the Buck Mountains mineral district is amajor manganese producer. The Palo Verde and Ideal mines in the northern part of thedistrict are located within an area of Precambrian crystalline rocks, and the ArizonaYucca mine appears to be within either Precambrian crystalline or mid-Tertiaryvolcanic rocks.

AGE: Unknown.


DISTRICT: CEDAR VALLEY

PRODUCTION: Au, Ag, Cu

GEOLOGIC SETTING: Small pods and lenses of marmatite, chalcopyrite, and galenareplacing altered black hornblende schists and grey siliceous schists. Gangue mineralsinclude quartz, pyrrhotite, magnetite, anthophyllite, tremolite, and pyrite. Ores fillopen fissures in schists and pegmatite dikes. In 1947 the ores assayed 10% combinedbase-metal sulfides with minor precious metal credits.

AGE: There is no direct evidence for the age of this district. Many of the mines inthis district are minor W producers. The description of this district is unlike anyother mid-Tertiary mineral district. There is no compelling evidence for amid-Tertiary age, and the metallogeny of the district would more likely indicate aPrecambrian or Mesozoic age for the deposits.

REFERENCES: #157

DISTRICT: CHEMEHUEVIS

GEOLOGIC SETTING: Precambrian schist locally cut by high-grade gold veins that tendto be irregular and narrow. The veins are filled with coarse-textured brecciatedwhite quartz, pyrite and galena, and are associated with diorite and granite porphyrydikes. Most mines in the district are tungsten prospects with erratic values ofscheelite in thin streaks. Both tungsten-rich and base- and precious-metal-rich veinsstrike northeast.

AGE: Keith and others (1983a,b) have assigned a mid-Tertiary age to this district.The presence of important tungsten prospects and northeast-trending veins and dikesbrings this age into question, and a Laramide age is considered possible.

26

DISTRICT: CLEOPATRA


GEOLOGIC SETTING: Copper carbonates, silicates, and oxides, and gold and silver, arepresent in replacement bodies of hematite and within veins of quartz, calcite, andlimonite. The veins strike northwest and dip to northeast. Paleozoic metasedimentshost most of the ore, in particular marbles and quartzites. The veins are part of alow-angle normal fault system.

AGE: This district is part of the Buckskin-Rawhide low-angle detachment system ofmid-Tertiary age.

REFERENCES: #19, #167, #168

DISTRICT: CYCLOPIC1) PRODUCTION: Au, Ag, Pb, Cu

GEOLOGIC SETTING: The Cyclopic district contains ores formed during two periods ofmineralization. The first stage of mineralization is characterized by high-angle,NE-striking, gold-bearing quartz veins that are the result of hydrothermal activityrelated to a nearby Cretaceous granite. Hosts rocks for this mineralization arePrecambrian rapakivi-type granite and gneiss. The Cretaceous gold-quartz veins werethen incorporated in a mid-Tertiary detachment fault zone. The second period of goldmineralization is characterized by pervasive argillic and localized ferric alteration.Ferric alteration, accompanied by gold mineralization, is confined to the hangingwall

of the detachment fault zone and to the footwall of high angle structures antitheticto the detachment surface.

AGE: Theodore and others (1982) state unequivocally that the deposits of the CyclopicMine are related to and localized by a west-dipping, mid-Tertiary, low-angle,detachment fault zone. Other deposits in the district are of inferred Cretaceous age.

REFERENCES: #127, #165, #179A, #194

j DISTRICT: EL DORADO PASS


GEOLOGIC SETTING: Gold is associated with iron oxides in the oxidized portion, andwith pyrite and galena in the unoxidized zones. Quartz and shattered quartz crystalsare the predominant gangue mineral in these steeply dipping veins. The veins cutPatsy Mine volcanics and Precambrian granite, gneiss and schist.

AGE: The veins are time equivalent or younger than the Patsy Mine volcanics ofMiocene age; therefore this district is of middle Miocene age.

REFERENCES: #12, #165, #194

27

DISTRICT: EMERALD ISLE


GEOLOGIC SETTING: Chrysocolla, tenorite, and cuprite filling fissure veins andcementing alluvium. This exotic copper accumulation is derived from the Mineral Parkporphyry copper deposit and related veins.

AGE: Although the district is designated mid-Tertiary by Keith and others (1983a,b),the alluvium is no older than Pliocene and is probably Quaternary (R. Scarborough,pers. comm., 1984).

REFERENCES: #51, #180, #181

DISTRICT: GREENWOOD

PRODUCTION: Au, Ag, Cu, Pb, (W)

GEOLOGIC SETTING: Precambrian granite, gneiss, aplite, and pegmatite locally overlainby Tertiary volcanic rocks. Half to five meter-wide veins of glassy quartz containingirregular disseminations and bunches of wolframite and scheelite with minorchalcopyrite. Iron and copper staining near the surface is abundant. Sericiticalteration of the wallrocks is noticeable.

AGE: Keith and others (1983a,b) consider this district to be a mid-Tertiary golddistrict. Reported gold production from this district is minor, and the district isprobably more correctly designated tungsten district. A Precambrian or Mesozoic ageis possible.

REFERENCES: #45, #119, #192

DISTRICT: LEAD PILL

PRODUCTION: Pb, Au, Cu, Ag

GEOLOGIC SETTING: Quartz veins with galena, fluorite, barite and gold cuttingPrecambrian gneiss. The veins are related to the intrusives at Potts Mountain. Therhyolites and andesites have a northwest-striking foliation.

AGE: No radiometric ages are available in the Potts Mountain area, but the geologicmap of Mohave County (Wilson and Moore, 1959) shows these rocks to be Tertiary.


DISTRICT: McCONNICO


GEOLOGIC SETTING: Gold and pyrite in pegmatitic dikes and shears cutting Precambrian

28

microcline granite. Gold is concentrated in an elluvial placer derived from onceoverlying mineralized rock. Hypogene ore is probably very low grade.

AGE: A mid-Tertiary age is suggested by Keith and others (l983a, b), but this isspeculative since there are insufficient data to make an age determination.


DISTRICT: McCRACKEN

PRODUCTION: Ag, Pb, Au, Cu

GEOLOGIC SETTING: Argentiferous galena with quartz-calcite-barite-gangue fillingfissure veins in Precambrian gneiss and schist. Evidence for brecciation is abundantin both veins and country rock. Keith and others (1983a,b) suggest that this districtis related to a mid-Tertiary low-angle breccia zone, perhaps suggesting detachmentrelated mineralization. However, some veins dip steeply (65) and theBuckskin-Rawhide detachment fault is probably several hundred meters below the surfacein this area.

AGE: Age is unknown, although if mineralization is related to detachment faulting,it is mid-Tertiary.


DISTRICT: MESA

PRODUCTION: Mn

GEOLOGIC SETTING: Psilomelane and pyrolusite in fractures and podiform masses cuttingcalcite marble, with less important bedded manganese deposits in reddish, sandysediments resembling the Chapin Wash Formation of Laskey and Webber (1949).

AGE: These sediments are probably correlative with the Miocene Chapin Wash formation.

REFERENCES: #63, #69, #137, #177

DISTRICT: MINNESOTA


GEOLOGIC SETTING: Horn silver in gangue of iron-stained, crushed and brecciatedquartz forming veins that flatten with depth. The veins cut Precambrian granitegneiss, schists, and Patsy Mine volcanics.

AGE: Several K-Ar dates indicate that the Patsy Mine volcanics are middle Miocene inage. The veins are clearly younger than earliest Patsy Mine volcanism, but areprobably related to the same pulse of mid-Tertiary magmatism. A mid-Tertiary ageseems almost certain.

29


DISTRICT: OATMAN


GEOLOGIC SETTING: Quartz-calcite-adularia veins bearing electrum cut the Gold Roadand Oatman latites. The veins strike NW and in many cases are associated withlate-stage rhyolite porphyry dikes. Sulfides are rare except for pyrite in wallrocksadjacent to the veins. Propylitic alteration is district wide, while analunite-illite-montmorillonite alteration assemblage lies above all productive veinsin the district.

~1 AGE: K-Ar dates from the Oatman district volcanics give late Oligocene to earlyMiocene ages. The mineralization is almost certainly related to volcanism, and henceis of mid-Tertiary age.

REFERENCES: #37, #118, #143, #165, #183

DISTRICT: OWENS

PRODUCTION: Ag, Au, Pb, Cu, Zn

GEOLOGIC SETTING: Veins and replacements above a mid-Tertiary detachment fault. Thisdistrict is in close geographic proximity to the Buckskin-Rawhide detachment faultsystem, and Keith and others (1983a,b) infer that mineralization is related tofaulting. A thorough literature review did not reveal any substantive geologicdescriptions of this mineral district, and the relationship of mineralization todetachment faulting should be considered speculative at present.

AGE: If mineralization is related to the Buckskin-Rawhide detachment fault, then thisis a mid-Tertiary mineral district; should this relationship not be demonstrable thenthe age should be considered unknown.

REFERENCES: #106, #107, #167, #168

DISTRICT: PILGRIM

PRODUCTION: Au, Ag

GEOLOGIC SETTING: Free gold in veins cutting across the fault contact betweenhangingwall rhyolites and footwall andesites. The volcanic rocks are probablyequivalent to the Patsy Mine volcanics. Rhyolite porphyry dikes are commonly found inthe fault zones. Veins are filled by quartz, calcite, pyrolusite and minor sulfides.Wallrocks are extensively silicified and brecciated. Red fault gouge and waxygreen-yellow quartz mark high-grade ore zones.

AGE: If these volcanic rocks are time equivalent with the Miocene Patsy Minevolcanics, then a mid-Tertiary age is appropriate. There is little doubt about the

30

correlation.

REFERENCES: #12, #165, #194

DISTRICT: PINE PEAK

PRODUCTION: Au, Zn, Pb, Ag, Cu

GEOLOGIC SETTING: Gold in a steeply-dipping, east-west striking, oxidized gouge zonecutting Precambrian amphibolite schist.

AGE: Keith and others (1983a,b), propose that this district is related to a northwesttrending dike swarm. Very little is known about this district, and lateCretaceous-Tertiary intrusives have been mapped in the vicinity. Although amid-Tertiary age has been proposed by Keith and others, a late Cretaceous - earlyTertiary age is a distinct possibility. Since most mid-Tertiary dikes in Arizona arenorthwest-trending, it would be especially important to establish a relationshipbetween mineralization and dike emplacement in order to more confidently propose amid-Tertiary age.

REFERENCES: #15, #106, #107

DISTRICT: RAWHIDE

PRODUCTION: Pb, Au, Cu, Zn, An

GEOLOGIC SETTING: Anglesite, cerussite, and chrysocolla with minor gold and silver inhematite replacement bodies. Host Paleozoic limestones overlie a low-angle normalfault underlain by mylonitic gneiss.

AGE: Mineralization is related to the mid-Tertiary Buckskin-Rawhide detachment fault,therefore the age of mineralization is mid-Tertiary.

REFERENCES: #15, #167, #168

1 DISTRICT: UNION PASS

PRODUCTION: Au, Ag

GEOLOGIC SETTING: Finely divided gold in quartz-calcite stringers, lodes, and veinscutting Precambrian Katherine granite and local rhyolite. Veins are commonlyassociated with rhyolite porphyry dikes are are nearly vertical and vuggy. High-gradezones are marked by the presence of adularia and/or manganese oxides. Fluorite andiron staining are also present. Wallrocks proximal to the veins are typicallyshattered and silicified; those distal from the veins may be kaolinized.

AGE: Mid-Tertiary age by analogy to the adjacent Oatman district.

REFERENCES: #118, #165, #194

31

DISTRICT: VIRGINIA

PRODUCTION: Au~ Ag~ Cu~ Pb

GEOLOGIC SETTING: Free gold in quartz-hematite-calcite veins with minor amounts ofadularia and epidote cutting Patsy Mine volcanics and Precambrian granites andmetamorphic rocks. Vein dips vary from steep to flat-lying. The mines are all nearthe Epperson Fault~ and veins are spatially associated with diabase dikes.

AGE: The veins of the district cut the mid-Tertiary Patsy Mine volcanics and areprobably related to the mid-Tertiary magmatic pulse. A mid-Tertiary age seems almostcertain.

REFERENCES: #12~ #124~ #165~ #194

DISTRICT: WHITE HILLS

PRODUCTION: Ag~ Au~ Cu~ Pb

GEOLOGIC SETTING: The source of ore in the White Hills district is NW striking~

moderately to steeply dipping veins cutting Precambrian(?) gneissic granite andamphibolite schist. The locally brecciated veins consist of quartz~ manganese andiron oxides~ silver chlorides and horn silver. Vesicular hornblende-augite andesiteand agglomerate overlie the basement. Schrader (1909) suggests the veins are relatedto feeder dikes of the overlying volcanic rocks.

AGE: The volcanic rocks of the White Hills district are probably correlative with theMt. Davis volcanics dated by Anderson and others (1972) as mid-Tertiary. Amid-Tertiary age for the White Hills district seems likely.

REFERENCES: #12~ #165

DISTRICT: YELLOW JACKET

PRODUCTION: Zn~ Ag~ .Au~ Cu~ Pb

1 GEOLOGIC SETTING: Keith and others (1983a~b) report that mineralization occurs asveins and replacements. The production data is from one year of mining activity inthe 1970's~ and as yet there is no published geologic information concerning thismineral district.

AGE: So little is known about this district that any age call is extremelyspeculative.

REFERENCES: #106~ #107

DISTRICT: YUCCA

PRODUCTION: Mn

32

GEOLOGIC SETTING: Wad-like oxides intimately mixed with sandy sediments in lensesinterlayered with barren sandstone, and cut by psilomelane and pyrolusite filledfractures. Fragments of brecciated country rock, calcite, barite, and iron oxides arethe primary gangue minerals in the fractures.AGE: The host rocks are probably correlative with the Miocene Chapin Wash Formationand thus the bedded manganese is Miocene in age. The veins are possibly related tohot springs of probable Miocene age.

REFERENCES: #63, #69, #136

PIMA COUNTY

t DISTRICT: ARAVACA, (OCEANIC)i

PRODUCTION: Cu, Au, Ag, Pb, Zn

GEOLOGIC SETTING: The country rocks of the Arivaca-Oceanic district are Mesozoicsandstones, conglomerates, and shales that are disrupted by east-west-trending faults.A second, lengthier set of faults trend N45W and are commonly intruded by Laramide

intermediate dikes. Ore minerals are argentiferous-auriferous galena, sphalerite,chalcopyrite, native gold, wolframite, scheelite, silver chlorides and pyrite.Mineralization is scattered and frequently associated with Tertiary-Cretaceousintrusives. Historically, three areas with various styles of mineralization havefallen under the Arivaca district. A Laramide tungsten district in the northwest LasGuijas Mountains, a gold-base metal district in the central and southern Las GuijasMountains, and a mid-Tertiary gold district in the San Luis Mountains are all includedin the Oceanic district as defined by Keith and others (1983).

AGE: The virtual absence of middle Tertiary rocks and the extensive outcrop ofCretaceous-Tertiary dikes make a late Cretaceous or Paleocene age most likely for thedeposits in the Las Guijas Mountains.

REFERENCES: #14, #102, #108, #197

DISTRICT: BABOQUIVARI

PRODUCTION: Au, Ag, Cu, Pb

GEOLOGIC SETTING: The Baboquivari Range has a complex history of Mesozoic throughTertiary magmatism with lower Jurassic silicic volcanics, an upper Jurassicgranodiorite batholith, early Tertiary granite, and a mid-Tertiary magmatic episodewith lamprophyre and rhyolite dikes. The Allison Mine is the major producer in thedistrict and has ore in pods and breccia related to dike swarms and sills. Nativegold, argentite, and silver-gold chlorides are the major ore minerals. Keith (1974)proposes a discernable district-wide metal zonation pattern where precious and basemetal mineralization is bound by tungsten on the north and south margins. Theorebodies are commonly associated with rhyolite dike swarms that yielded a 26 m.y.K-Ar age.

33

1

AGE: The probable genetic association of the orebodies with the dated rhyolite dikesindicates a mid-Tertiary age.

REFERENCES: #53, #66, #68, #84, #88, #101, #108, #185, #194

DISTRICT: BEN NEVIS

PRODUCTION: Ag, Au, Cu, Pb

GEOLOGIC SETTING: This small district is characterized by quartz-calcite-barite veinscutting Tertiary rhyolites. The typically epithermal veins follow fault zones in anirregular and lensing fashion. Free gold and silver chlorides are the primary oreswith a minor base metal component.

AGE: The mines of the Ben Nevis district are localized along the contact betweenTertiary rhyolite and andesite (Rytuba and others, 1978). This volcanic package is asyet undated, although a Miocene age is probable for these units, and the districtitself •

REFERENCES: #75, #101, #160

DISTRICT: BLACK DRAGON

PRODUCTION: Mn

GEOLOGIC SETTING: Hard and soft wad-type oxides with small amounts of pyrolusi'te havepartially replaced, and occur as coatings and narrow fracture fillings in, a shearedor fractured rhyolite. Haxel and others (1980) map the area as Jurassic rhyodaciteporphyry of the Mulberry Wash Volcanics Formation. The mineralized zones arediscontinuous for nearly 700 meters of strike length. The mineralized fractures canbe traced along the surface by their capping of desert varnish.

AGE: The mineralization is hosted by Jurassic rocks; therefore, the age ofmineralization is Jurassic or younger.

REFERENCES: #70, #84, #101

DISTRICT: CADILLAC

PRODUCTION: Mn

GEOLOGIC SETTING: Seventy meters of strike length have been explored along the faultcontact between Tertiary fine-grained basalt and vesicular basalt; the contact strikesN15W, and dips 60E. Manganese minerals are present in a breccia zone 1-2 meters wideagainst the vesicular basalt. Psilomelane has replaced much of the cementing materialof the breccia zone and appears as rims around unreplaced basalt fragments. Adjacentto the breccia zone the sheared and shattered basalt contains manganese oxides in thinfracture fillings and small nodules.

34

AGE: Kahle and others (1978) assign a Tertiary age to the host basalts; therefore,the age of mineralization is Tertiary or younger.


DISTRICT: CERRO DE FRESNAL


GEOLOGIC SETTING: The Cerro de Fresnal District is on the western margin of anextensive northeast-trending silicic volcanic field. The western edge of the districtis in a Laramide granite. Ore minerals include silver and gold chlorides in a fissurezone, and weathered and oxidized quartz veins with free gold and silver.

AGE: Keith and others (1983a,b) infer that a 30 to 25 m.y.-old northwest-strikingdike swarm is the agent of mineralization. However, a genetic relationship betweenmineralization to dike emplacement has not been established, and a Laramide age ofmineralization is a distinct possibility.


DISTRICT: RINCON


GEOLOGIC SETTING: The Rincon district is in the upper plate of the mid-TertiaryCatalina detachment fault. The Colossal Cave area is dominated by the southwestdipping Catalina detachment fault and numerous north-trending normal faults. ALaramide pluton intrudes Precambrian Apache Group and Paleozoic sediments.Mineralization includes spotty pockets of lead and copper oxides as replacements inPaleozoic limestbnes. Epidote, pyrite, garnet, and limonite accompany extensivesilicic alteration. A brecciated-barite bearing fault zone in Paleozoic limestonerepresents a separate style of mineralization.

AGE: Mid-Tertiary structural disruption in this area has been severe. It is likelythat the brecciated barite in the fault zone is mid-Tertiary, but the age of thereplacement deposits is uncertain. Mid-Tertiary replacement deposits in limestoneoccur above mid-Tertiary detachment faults in western Arizona, indicating that thereplacements could be mid-Tertiary.

PINAL COUNTY

DISTRICT: COPPER BUTTE

PRODUCTION: Cu, Ag, Au, Pb

35

GEOLOGIC SETTING: The Copper Butte deposit is in the Oligocene Whitetailconglomerate. The conglomerate is poorly sorted and consists of angular clasts ofPinal Schist. The Whitetail variously rests on Precambrian Pinal Schist intruded byRuin Granite) or upon Paleozoic sediments. The deposit and its enclosing conglomerateare bounded by Miocene Apache Leap Tuff. Ore minerals are chrysocolla and blackcopper wad. The deposit is not clastic copper, but rather it is a precipitate fromgroundwater. The protore source is unknown and Philips (1976) suspects the nearbypresence of an as yet unfound porphyry copper deposit. However, it is possible thatprior to middle to late Tertiary low-angle normal faulting, the deposit was locatedcloser to porphyry copper mineralization near Ray.

AGE: By analogy to other exotic copper bodies, the mineralization is presumed to bemiddle to late Cenozoic.

REFERENCES: #13, #140, #141) #185

DISTRICT: CRESCENT

PRODUCTION: Mn

GEOLOGIC SETTING: The most important manganese deposits are along fracture zones inthe Precambrian Mescal Limestone and Dripping Spring Quartzite. A few small depositshave been found along narrow fractures in the fanglomerates of the San ManuelFormation which overlie the Precambrian rocks. Most of the mineralized fracture zonesfollow bedding planes in the older rocks. The ore minerals consist of psilomelane,pyrolusite, and manganite, which occur in irregular lenticular masses) veinlets) andinterlacing seams surrounding fragments of unreplaced wallrocks. The chief gangueminerals are iron oxides) quartz, and calcite.

AGE: The presence of deposits in the mid-Tertiary San Manuel Formation indicates amid-Tertiary or younger age. We favor a mid-Tertiary age because this was a time ofwidespread magmatism and tectonism, in contrast to younger) relative quiescence.

REFERENCES: #70

DISTRICT: GREENBACK

PRODUCTION: Au, Ag) Cu

GEOLOGIC SETTING: The general geology of the Greenback district is characterized bylate Cretaceous through middle Tertiary volcanics and minor faulting. Laramidegranite) hornblende porphyry) and dacite constitute the majority of outcrops. TheCopperosity Mine is the major producer in the district. Here the ore occurs in veins)and replaces Paleozoic limestone. Ore minerals are chrysocolla, malachite) azurite)copper pitch) and native copper. Gangue are jasper, hematite, goethite) and jarosite.Other deposits occur as quartz veins in dacite and granite. The Greenback districtmay be distal and contemporaneous with the Pinal Grande mineral district, a porphyrycopper system.

AGE: The abundance of Laramide intrusives in the area is suggestive of a Laramide

36

age.

REFERENCES: #15, #30, #35, #52, #196

DISTRICT: MAMMON


GEOLOGIC SETTING: The Mammon District lies mostly in Precambrian Pinal schist. Thedistrict's northern perimeter contains Precambrian Apache Group sediments cut by amajor N20-trending fault and numerous lesser E-W trending faults. The northernreaches of the district contain similarly faulted sections of Paleozoic sediments.District ore geology includes limestone replacements in Mississippian Escabrosalimestone; vein fillings in Laramide(?) andesite porphyry with oxides and sulfates oflead, zinc, silver, vanadium, and free gold with notable advanced argillic alteration;schist-hosted quartz veins with chrysocolla, malachite, cerargyrite, wulfenite,vanadiriite; and free gold with epidote, chlorite, pyrite gangue at the Mammon mine.

AGE: The presence of pebble dikes, the lead-zinc-copper element suite, and theproximity of the 67 m.y.-old Lakeshore porphyry copper all suggest Mammonmineralization may be related to the Laramide Lakeshore system.

REFERENCES: #15, #27, #81, #84, #85, #91, #97, #185

DISTRICT: MAMMOTH

PRODUCTION: Pb, Au, Cu, Zn, Mo, Ag

GEOLOGIC SETTING: Precambrian Oracle quartz monzonite is the major country rock ofthe Mammoth district. Tertiary intrusive rhyolite breccia is the predominant orehost, and Oracle quartz monzonite is a lesser host. Mineralization centers on thenorthwest-trending Mammoth and Dream faults, and is associated with significantsilicic alteration. Sphalerite, galena, and molybdenite are the major ore mineralswith fluorite and barite as common gangue.

AGE: The veins intrude the late Oligocene Cloudburst volcanics and are cut by thej Miocene San Manuel fault; this indicates a mid-Tertiary age.

REFERENCES: #34, #39, #115, #139, #166

DISTRICT: MARTINEZ CANYON

PRODUCTION: Pb, Ag, Cu, Au, Zn

GEOLOGIC SETTING: The Martinez Canyon district is in a thin sequence of Miocenesiliceous volcanics that rest on Precambrian Pinal Schist. Most of the mines fallalong a north-trending fault system. The mineralogy includes galena, cerussite,anglesite, hematite, azurite, chrysocolla, pyromorphite, cerargyrite, embolite,quartz, limonite, fluorite, and barite.

37

AGE: Creasey (1978) reports dates on biotite of 17.4 m.y.B.P. for the quartz latitewhich is assumed to be contemporaneous with mineralization.

REFERENCES: #15, #164, #178, #179, #185

DISTRICT: MINERAL HILL

PRODUCTION: Ag, Cu, Au, Pb, Zn

GEOLOGIC SETTING: Pinal Schist is the prevailing country rock in the Mineral Hilldistrict. North- to N40W-trending shear zones punctuate the terrane and controlmineralization. Galena dominates with lesser sphalerite, cerargyrite, argentite,cerussite, and anglesite. ABGMT file data include the Reymert Mine as the northernextension of the district. The Reymert has black calcite, manganese-silver ore whichis frequently characteristic of mid-Tertiary precious metal mineral districts.

AGE: ABGMT file data and Keith and others (1983a,b) infer that 18 to 15 m.y.-old,quartz latite dikes adjacent to the district are genetically related tomineralization. A north- to northwest-trend of the mineralized shear zones issupportive of a mid-Tertiary age.

REFERENCES: #16, #164, #179, #185

DISTRICT: MINERAL MOUNTAIN


GEOLOGIC SETTING: The Mineral Mountain occurrence is similar to Martinez Canyon. Thegeology of the district is characterized by an intensely faulted section ofPrecambrian crystalline rocks that are overlain by Miocene silicic volcanics andintruded by domiriantly N25W~ to riorth~trending quartz latite dikes. The vast majorityof the mineralization is localized along these dikes. The south end of the districthas a east-west- to N80W-trending fault zone that marks the southern end ofmineralization. Galena, anglesite, cerussite, native gold, and native silver are oreminerals.

(j AGE: Theodore and others (1978) propose a late Cretaceous-early Tertiary age for the

deposit by inference that mineralization is related to the 71 m.y. Mineral Mountainpluton. In contrast, ABGMT file data and Keith and others (1983a,b) infer amid-Tertiary age based on the close association of mineralization with 15.8 to 17.4m.y.-old quartz latite dikes. The Miocene age of mineralization is preferred.

REFERENCES: #178, #179, #185

DISTRICT: OWL HEAD


GEOLOGIC SETTING: The Owl Head mineralization is restricted to middle Tertiary

38

Theconsiststhe

volcanic rocks that rest on the Guild Wash low-angle, normal fault. Beneath thisdetachment surface are the mylonitized Precambrian rocks of the Tortolita and SuizoMountains. Chalcocite, chrysocolla, and chalcopyrite are common. Malachite, azurite,native gold, argentiferous galena, argentite, and tenorite .are also reported.Specularite is extensive as is sericitic and propylitic alteration. Local placermagnetite deposits have recorded production.

AGE: A mid-Tertiary age for mineralization is almost certain based on the associationof mineralization with a ~id-Tertiary fault and with mid-Tertiary volcanic rocks.

REFERENCES: #22, #23, #24, #25, #32, #104

DISTRICT: PICACHO


GEOLOGIC SETTING: Two ar.eas, one in the vicinity of Picacho Peak and a second to theNE, both fall within the Picacho district as defined by Keith and others (1983a,b).The southern part of the district, near Picacho Peak at the SSW end of the PicachoRange, consists of a basalt and basaltic agglomerate of Miocene age, and is in theupper plate of a detachment fault. Northwest-trending structures control themineralization which consists of chrysocolla, copper oxides, and specularite.northern part of the district is in the main portion of the Picacho Range andof mylonitic Precambrian and Cenozoic rocks. This area is the lower plate ofdetachment terrane and the mylonitic gneisses appear to represent a northwestcontinuation of mylonitic gneiss in the Rincon, Santa Catalina, and Tortolitamountains. Mineralization here consists of chrysocolla, malachite, azurite, andextensive specularite in quartz veins. The deposits are in Precambrian granite gneissand diabase dikes with occasionally associated andesite dikes.

AGE: The association of mineralization with a mid-Tertiary low-angle normal fault andwith mylonitic gneiss of probable mid-Tertiary age is suggestive 6f a mid-Tertiaryage. Mineralization within mid-Tertiary volcanic rocks at the southwest end of therange must be mid-Tertiary or younger.

REFERENCES: 1122, tI2 9, 1152

}

)-' DISTRICT: RANDOLPH

PRODU CTION: Ag, Pb, Au, Cu

GEOLOGIC SETTING: Keith and others (1983a,b) infer northwest-striking, middleTertiary veins to be associated with a probable 18-15 m.y.-old northwest-strikingrhyolitic dike swarm. ABGMT file data indicates that the veins trend northeast andcut Precambrian diabase and granite.

AGE: The northeast trend of the veins, if true, is suggestive of a Laramide age.

REFERENCES: #106, #107, #147

39

DISTRICT: SAWTOOTH

PRODUCTION: Mn

GEOLOGIC SETTING: The Sawtooth district in the northern end of the SawtoothMountains, contains deposits that are hosted by Tertiary basalt, latite, andtrachyandesite flows and are confined to northeast- or northwest-striking,steeply-dipping fractures and faults. Ore occurs as lenses, pods, replacements, andveinlets in and surrounding brecciated fragments of the country rock. Manganeseoxides, psilomelane and pyrolusite are found in a gangue of calcite, which is locallymanganiferous.

AGE: The manganese ores are hosted by undated Tertiary volcanics, which arelithologically similar to known mid-Tertiary volcanics in neighboring mountain ranges.

The age of mineralization is likely mid-Tertiary.


DISTRICT: SILVER REEF

PRODUCTION: Ag, Cu, Au, Pb

GEOLOGIC SETTING: Mineralization in the Silver Reef district is intimately associatedwith Tertiary vesicular andesite that overlies Oracle Granite and with dikes thatintrude Pinal Schist. The deposits are localized along east-west trending faults andfissures. Native silver, galena, argentite, cerargyrite, wulfenite, vanadinite,,: andchrysocolla are reported ore minerals.

AGE: The volcanics have been dated at 25.3 m.y.-old and presumed to becontemporaneous with ore formation. A younger age is possible for the mineralization.

REFERENCES: #20, #27, #36,

DISTRICT: SLATE

PRODUCTION: Ag, Au, Pb, Cu

GEOLOGIC SETTING: deposits consist of veins and limestone replacement occurrencesrelated to andesite porphyry dikes and sills. Silver-rich galena and free gold arefound associated with quartz, pyrite, and sphalerite. The veins are extensivelybrecciated, and the wallrocks are silicified, pyritized, sericitized, and argillized.Replacement deposits are confined to Paleozoic limestones that are recrystallized andpyritized. Both vein and replacement deposits are oxidized as indicated by abundantiron and manganese oxides and base metal oxides and carbonates.

AGE: These deposits are intimately related to andesite dikes and sills.Heindl(1960) correlates the dikes and sills of the Slate Mountains with those of theAjo area and/or the Tucson Mountains, both of Laramide age. These correlations arehighly speculative, so the age of mineralization could be either Laramide ormid-Tertiary.

40


DISTRICT: SUPERSTITION MOUNTAINS

PRODUCTION: AUt CUt Ag

GEOLOGIC SETTING: The Superstition Mountains prospects are along an east-west trendthat flanks the southern end of the Superstition volcanic complex. The volcaniccomplex is a thick t diverse sequence of Miocene age. Mineralization occurs in bothPrecambrian Ruin Granite and Tertiary volcanics. Peterson and Jinks (1983) describe apredominantly base metal character in contrast to the gold-pyrite ore of the nearbyGoldfield district t and report that there has been no production from the SuperstitionMountains district.

AGE: A middle Tertiary or younger age is certain since deposits are in part hosted bymiddle Tertiary volcanic rocks.


DISTRICT: TABLE MOUNTAIN

GEOLOGIC SETTING: Rocks of the Table Mountain area are cherty and dolomiticMississippian Escabrosa Limestone overlain unconformably by the lower andesite unit ofthe middle Tertiary Galiuro Volcanics. The north end of the eastern contact betweenthe limestone and volcanics is a northwest-striking fault t but the remaining contactsare depositional (Simons t 1964). The principal ore-bearing rock is a layer of gray ormottled red t broWTI t and white massive jasperoid or jasperoid breccia. The jasperoidzone contains chrysocolla, malachite, azurite, dioptase, and otherand carbonates. The ore minerals are fourid in irregular concentrations and pods alongfault and joint surfaces. Other than jasperoid t only quartz and barite are commongangue minerals.

AGE: The Table ~ountain deposits may have Been derived from the nearby LaramideCopper Creek porphyry copper system to the southwest as Keith and others (1983b)suggest. Simons (1964) suggests that ore deposition occurred prior to the depositionof the Galiuro volcanics t but the age of mineralization is not well constrained,except that it predates the Galiuro Volcanics.

DISTRICT: WOOD CAMP CANYON


GEOLOGIC SETTING: Keith and others (1983a tb) suggest that the Wood Camp Canyondistrict is a middle Tertiary porphyry copper system associated with the Wood CampCanyon pluton. Lowell (1974, and pers. comm. t 1985) describes disseminated copper

41

mineralization of subeconomic grade and tonnage in this area.that the intrusive relationships between the Wood Camp plutonLeap Tuff are uncertain. Map relationships suggest that thiscontact with the Apache Leap Tuff and may not be intrusive.

Peterson (1960) statesand the overlying Apachepluton is in fault

AGE: The age of this district depends critically upon the nature of the Wood CampCanyon pluton - Apache Leap Tuff contact. If this contact is intrusive t then thedistrict is of middle Tertiary age t but if this is a fault contact t as map relationssuggest t then the Wood Camp Canyon mineralization is more likely Laramide.

REFERENCES: #124A t #136B

DISTRICT: ZIG ZAG

PRODUCTION: Mn

.~ d 1 1, GEOLOGIC SETTING: Har psi orne ane occurs in a gangue of manganiferous calcite andquartz in high-grade streaks and veinlets along three parallel veins in coarse-grainedgranitic rocks. The veins strike NI0W to N25W t dip steeply to the southwest t and areup to 30 meters apart. Where the granite is shattered t a network of thin seams ofmanganese minerals may extend outward for several meters beyond the veins.

AGE: The age of this district is unknown t but may be middle Tertiary based on thenorth-northwest strike of the veins.

REFERENCES: inO

SANTA CRUZ COUNTY

DISTRICT: AUSTERLITZ - YELLOW JACKET

PRODUCTION: AUt Ag t CUt Pb

GEOLOGIC SETTING: Mineralization in the Austerlitz district is found in tabularlenses associated with northwest-trending rhyolite dikes. The Jurassic Cobre Ridgetuff is the major country rock. Quartz veins containing native gold t native silver tchrysocolla t and pyrite are the ore assemblage. The Little Doe Mine hosts minoruranium mineralization.

AGE: The northwest trend of rhyolite dikes intimately associated with the ore issuggestive of a middle Tertiary age.

REFERENCES: #71, #108, #113 t #185

DISTRICT: CAVE CREEK

PRODUCTION: Cu, Ag t Pb

42

t

1

GEOLOGIC SETTING: The Cave Creek district as defined by Keith and others (1983a)b) ispoorly known. The deposits consist of spotty) oxidized) silver-rich) coppermineralization filling fault contacts and along intrusive contacts. The deposits arehosted by Cretaceous Fort Crittenden Formation and Triassic Mount Wrightson Formation(Drewes) 1971).

AGE: Keith and others (1983a,b) propose a mid-Tertiary age for this district basedupon a spatial relationship with rhyolitic dikes of Oligocene(?) age (Drewes, 1972).The dikes are undated; yet they post-date regional Laramide mineralization andunconformably underlie Oligocene age Pantano Formation (Drewes) 1972). Drewes (1972)proposes a Paleocene to Oligocene age for these rocks. The genetic relationshipbetween these dikes and the Cave Creek occurrences is not at all clear, and furthergeologic evaluation is necessary to document the importance of these dikes to theweakly mineralized Cave Creek deposits. A Laramide age for this district ispermissible. The Cave Creek district is ringed by Laramide age mineral districts(Keith and others) 1983a)b).

REFERENCES: #55) #56) #102

DISTRICT: ORO BLANCO

PRODUCTION: Pb, Zn) Ag) Au) Cu

GEOLOGIC SETTING: Mesozoic rhyolites) quartz latite ash flows, tuffs, and arkoseoverlain by late Cretaceous terrestrial sediments are the major stratigraphic units inthe Oro Blanco district. Laramide plutons are abundant and include the lateCretaceous Ruby Diorite and the Paleocene-Eocene Sidewinder Quartz Monzonite. Threetypes of ore are noted: quartz veins filling fractures with lenses containing galena)chalcopyrite) sphalerite) tetrahedrite) and pyrite; native silver and gold in flat)shallow faults with strongly pyritized and silicified quartz monzonite dikes; andsteeply dipping) tabular zones of argillitizedmineralization.

AGE: The near absence of middle Tertiary igneous rocks, the overwhelming abundance ofCretaceous through Paleocene intrusives, and the varied base metal character of theore all suggest a Laramide) not middle Tertiary, age. The presence of precious metalmineralization in low-angle faults and occasional uranium values suggest that somemineralization is middle Tertiary, although the production statistics point topreeminence of the Laramide age deposits.

REFERENCES: #102, #111) #113) #185, #187

YAVAPAI COUNTY

DISTRICT: BATTLE FLAT

PRODUCTION: Ag, Cu, Au, Pb, Zn

GEOLOGIC SETTING: Bedrock within the Battle Flat district consists of the Precambrian

43

Brady Butte granodiorite and surrounding metasediments of the Texas Gulch Formationand metavolcanics of the Spud Mountain volcanics. Ore is associated withnortheast-trending feldspar porphyry dikes of possible Laramide age that parallel thetrend of foliation and faulting in the Precambrian rocks. The orebodies consist ofquartz-pyrite veins with native silver, silver chlorides and oxides, and argentiferousgalena. Spatz (1974) describes a similar geologic setting for parts of the Pine Flatdistrict,S km to the north; this district is a porphyry copper prospect of Laramideage.

AGE: Keith and others (1983a,b) suggest a mid-Tertiary age for the veins of theBattle Flat district. The northeast trend of the veins and proximity to the Pine Flatdistrict suggest that this district is of Laramide age.

REFERENCES: #7, #120, #173, #185

DISTRICT: BLACK CANYON

PRODUCTION: Au, Ag, Pb, Cu, Zn

GEOLOGIC SETTING: The bedrock of the Black Canyon district consists of Precambrianmetasedimentary and metavolcanic rocks near and within the north-trending Shylockfault zone. The southern portion of the district is adjacent to the Precambrian CrazyBasin batholith. Dikes ranging in composition from basalt to rhyolite are, in manyareas, spatially if not genetically related to the ore deposits. Native silver, rubysilver, silver chlorides and minor free gold are common ore minerals. Precious metalmineralization is associated with galena, pyrite, sphalerite, and minor chalcopyritein low-angle quartz-calcite-siderite veins. The veins are discordant to the dominantnortheast-trending foliation of the Precambrian metamorphic rocks, and commonly dip tothe southeast. Wallrocks are locally affected by intense sericitization andsilicification.

AGE: The dikes associated with mineralized material in the Black Canyon district areundated, but thought to be Miocene (E. DeWitt, written corom.). The high silvercontent and low-angle nature of the veins also points to a mid-Tertiary age ofmineralization according to DeWitt (written comm.).

REFERENCES: #4, #5, #6, #114, #120, #185, #194

DISTRICT: BLACK DOME

PRODUCTION: Mn

GEOLOGIC SETTING: Pyrolusite and psilomelane occurring in fractures, seams, and smallirregular masses surrounding brecciated fragments of Miocene volcanic rocks andPrecambrian granitic rocks. The deposit also contains large amounts of calcite(travertine?), much of it manganiferous.

AGE: The deposits are hosted, in part, by mid-Tertiary volcanic rocks, indicatingthat they are mid-Tertiary or younger in age. A middle to late Tertiary age is

44

favored as this was a time of widespread magmatism.

REFERENCES: #69

DISTRICT: BLACK HILLS

PRODUCTION: Cu, Ag, Au, Pb, Zn

GEOLOGIC SETTING: There is scant information available for this district. Lindgren(1926) describes the deposits as consisting of quartz-calcite veins with variableamounts of sphalerite, galena, pyrite, bornite, tetrahedrite, and tennantite. Oxidizedportions of the veins are characterized by ankerite, azurite, and malachite. Theeast-west-trending, low-angle veins cut the volcaniclastics of the upper unit of thePrecambrian Grapevine Gulch Formation near the north-trending Shylock Fault.

AGE: The district has been designated mid-Tertiary by Keith and others (1983a,t because the deposits are related to a series of east-west-trending dikes. The

presence of these dikes is not confirmed in the literature; they are neither mapped byAnderson and Creasey (1967), nor described by Lindgren (1926). The timing of thismineralization is unknown and the basis of Keith and others's (1983) age determinationis equivocal. E. DeWitt (written comm.) proposes that the high silver and leadcontent and low-angle nature of the veins suggests a mid-Tertiary age.


DISTRICT: BLACK ROCK

PRODUCTION: Au, Cu, Ag, Pb, Zn

GEOLOGIC SETTING: The bedrock in the Black Rock district consists of Precambrianamphibolite-grade metaigneous rocks, grahite gneiss, and granite. Northwest-strikingMiocene(?) rhyolite porphyry and mafic dikes cross-cut the east-northeast-strikingfabric of the Precambrian rocks. The mafic (andesite?) dikes are locally altered andcross-cut by epithermal quartz-pyrite-siderite-fluorite veins. Chalcopyrite, galena,arsenopyrite and tetrahedrite are common ore minerals. Secondary specularite andchrysocolla occurs locally in the northwest-striking high-angle quartz-sulfide veins.The Monte Cristo mine contains nickel-cobalt arsenates and sulfides (Nichols, 1983).In contrast, the Grijalva and Oro Grande mines are characterized by pyriticcopper-gold ores in thick, high-angle, northeast-striking quartz veins. The lattertwo vein deposits may have been rotated during middle Tertiary faulting.

AGE: The majority of the Black Rock district orebodies.have northwest trends and,therefore, appear to be associated with mid-Tertiary listric normal faults that rotatePrecambrian basement and the Tertiary volcanic cover in the Wickenberg area. Thedistinctly different trend and character of the Grijalva and Oro Grande mines suggestsa Laramide age for these deposits.

REFERENCES: #4, #5, #79, #84, #134, #185, #194

45

1

DISTRICT: BOX CANYON

PRODUCTION: Mn

GEOLOGIC SETTING: Manganese mineralization occurs along steeply- dipping fractures ina volcanic breccia. The highest grade ore is found in disconnected lenticular bodiesspaced discontinuously along the fracture zones. The manganese minerals, consistingof a mixture of the common oxides, occur as irregular shoots and veinlets surroundingunreplaced fragments of the volcanic breccia. Calcite, quartz, and wallrock inclusionsare the principal components of the gangue.

AGE: Volcanic breccias manganese deposits are probably mid-Tertiary in age,indicating that mineralization is mid-Tertiary or younger. A mid-Tertiary (early tomiddle Miocene) age is favored.

REFERENCES: #69

DISTRICT: BURMISTER

PRODUCTION: Mn

GEOLOGIC SETTING: Psilomelane with opal and chalcedony in disconnected massesdistributed erratically within a flat-lying bed of travertine interbedded with theHickey Formation.

AGE: The Hickey Formation is composed dominantly of basalt of middle to late Mioceneage, therefore, the manganese deposits late Miocene.

REFERENCES: #69

DISTRICT: BULLARD


GEOLOGIC SETTING: The Bullard district includes two areas of mineralization: the areaaround Bullard Peak near the foot of the eastern Harcuvar Mountains, and the NellieMeda Mine northeast of Aguila. The mines near Bullard Peak lie in close proximity tothe Bullard detachment fault. The deposits consist of copper-stained fault gouge withquartz, calcite, barite, and minor fluorite. The brecciated and oxidized ore consistsmainly of chrysocolla and malachite with minor chalcopyrite. Hematite and manganeseoxides are also prevalent. The wallrocks are interbedded Miocene andesites andsandstones.

AGE: Mineralization in the Bullard Peak area occurs within andesites that have beendated by Scarborough and Wilt (1979) as Miocene. The presence of a nearby detachmentfault and dated volcanic rocks indicate that mineralization is mid-Tertiary in thisarea. Ore deposits of the Nellie Meda mine are hosted by Precambrian crystallinerocks, and are of uncertain age.

REFERENCES: #21, #153, #163

46

DISTRICT: CASTLE CREEK


GEOLOGIC SETTING: The country rocks in the Castle Creek district are many and varied.Precambrian metasedimentary schists with a northeast-trending foliation predominate,

Precambrian granite crops out locally, and Tertiary(?) andesite to rhyolite flows aretypically associated with mineralization. A NI0W to N40W trending, low-angle fault isthe dominant locus of mineralization. Native gold, galena, sphalerite, chrysocolla,copper carbonates, and chalcocite are ore. Quartz, limonit~, barite, pyrite,tourmaline, and abundant specularite are gangue. Lindgren (1926) outlines evidencethat the copper-gold and lead veins are pre-middle Tertiary. This argument is noteasily supported and the varied mineralogy suggests more than one phase of oreformation. The Independence Mine, for example, has native silver, argentiferousgalena, and beryl, in contrast to the scheelite and psilomelane of the Black Butteprospect. Both of these are markedly different from the copper-gold suite of themajor properties.

AGE: None of the ore deposits have been dated by radiometric techniques, and thedistinct mineralogy of some of the properties suggest more than one ore forming event.

The pervasiveness of specularite along the gently dipping faults, and association ofprobable Tertiary dikes with mineralization favor a mid-Tertiary age for thesedeposits.

REFERENCES: #120, #123, #185, #194

DISTRICT: CROSBY


GEOLOGIC SETTING: Little geologic information is presently available for the depositsof the Crosby district. Wilson (1967) described rt6rtheast~strikingveinsquartz with disseminations of pyrite in the unoxidized levels. Oxidized ore consistsof brecciated quartz and limonite with free gold adsorbed onto the limonite. Thecountry rock is Precambrian schist and granite which is locally sericitized adjacentto the veins.

AGE: Keith and others (1983a,b) describe this district as mid-Tertiary veins in and~ near a low-angle normal (detachment) fault. E. DeWitt (written comm.) suggests the

geometry of the veins are indicative of mineralization related to a low-angle normalfault of probable mid-Tertiary age.

REFERENCES: #194

DISTRICT: DATE CREEK

PRODUCTION: U, V

GEOLOGIC SETTING: Stratabound, uraniferous mudstone, tuffaceous mudstone, marlstone,and limestone within a 260 m thick, unconformity-bounded sequence of primarily

47

mudstone and limestone that forms the Anderson Mine Formation of Sherborne and others(1979) and is within the mid-Tertiary Chapin Wash Formation (Otton, 1981). Uraniummineralization typically occurs in 1-3 m-thick zones that are associated withcarbonaceous mudstone. Uranium-rich sediments typically contain 0.03 to 0.08 % U308occurring in amorphous silica and associated with pyrite. Local oxidized ore innear-surface deposits contains as much as 30% U308 as carnotite and tyuyamunite.

AGE: Host sediments are early to mid-Miocene in age. Unoxidized uranium is probablyof about the same age, whereas remobilization and concentration of oxidized uraniumore may have occurred in late Tertiary or Quaternary time.

REFERENCES: #131, #135, #136, #169

DISTRICT: FRENCH GULCH


GEOLOGIC SETTING: The French Gulch district is in Precambrian granite. The dearth ofdescriptions from French Gulch preclude a detailed summary. French Gulch has a lowerbase-metal component and a high pyrite content, but is otherwise similar to the WalnutGrove district, suggesting a similar age and origin.

AGE: Keith and others (1983a,b) designate the French Gulch deposits as mid-Tertiary.The presence of Laramide gold-copper deposits in the area, however, favors a Laramideage for this district.

REFERENCES: #17, #89, #185

DISTRICT: GROOM CREEK

PRODUCTION: Au Ag, Cu, Zn, Pb

GEOLOGIC SETTING: The Yavapai Series Green Gulch volcanics and Government Canyongranodiorite are the major hosts for the Groom Creek district. Cretaceous-Tertiary(?)rhyolite porphyry dikes, which are parallel or subparallel to the NI0E-trendingPrecambrian foliation, are associated with mineralization in the area. These dikesare probably related to the 64 m.y.-old Walker stock. Orebodies are fault controlledand typically have native gold, galena, and pyrite. About two-thirds of the propertiesshow minimal copper with the other third having notable chalcopyrite. The SilverFlake mine is uraniferous. The geologic setting of the Groom Creek is similar to thatof the Mount Union and Hassayampa districts.

AGE: Keith and others (1983a,b) favor a mid-Tertiary age on the basis of thegeochemical signature of the deposits. The close association of Laramide(?) rhyoliteporphyry dikes with ore, and the proximity of the Laramide Walker mineral district ofsimilar geologic setting suggests that the deposits of Groom Creek are Laramide ratherthan mid-Tertiary.

REFERENCES: #7, #112, #185, #194

48

DISTRICT: HARRIS

PRODUCTION: Mn

j GEOLOGIC SETTING: Lenticular ore shoots of pyrolusite and psilomelane occurring in agangue composed of brecciated sandstone, calcite, and barite, in a well-definednorthwest-striking, steeply northeast-dipping vein cutting red, southwest-dippingMiocene sandstone.

AGE: The host sandstone is Miocene, therefore, the manganese deposits are Miocene oryounger; a Miocene age of mineralization is preferred.


DISTRICT: HASSAYAMPA

1 PRODUCTION: Au, Ag, Pb, Cu, Zn

GEOLOGIC SETTING: The bedrock geology of the Hassayampa district consists ofamphibolites, slates, metarhyolites, and rhyolites of the Yavapai series Green Gulchformation. Mineralization is associated with dikes and veins that parallel aN15E-trending Precambrian foliation. Chalcopyrite, native gold, sphalerite, galena,and tetrahedrite are ore minerals. Quartz, pyrite, fluorite, and calcite areprevalent gangue. The Hassayampa district seems very similar to the nearby GroomCreek, Mt.Union, and districts.

AGE: E. DeWitt (written comm.)based on the northeast-trend ofLaramide districts in the area.based on the element suite.

REFERENCES: #7, #181, #193

DISTRICT: HUMBUG


believes Hassayampa is of late Laramide age, in partthe dikes and veins, and similarity to other knownKeith and others(1983a,b) favor a middle Tertiary age

GEOLOGIC SETTING: Precambrian Crazy Basin quartz monzonite, and mica schists of theYavapai Series comprise the bedrock of the Humbug district. Tertiary(?) rhyoliteporphyry dikes striking N40E to NSOE and dipping 80NW are typically associated withore. Pyrite, galena, sphalerite, arsenopyrite, native gold, ruby silvers, silverhalides, and chalcopyrite in quartz veins are the ore assemblage. Wilson and others(1967) mention that sericitic alteration is pervasive in the wallrocks.

AGE: Keith and others(1983a,b) favor a middle Tertiary age. However, the northeasttrend of the dikes, and the similarity of this district to the Walker, Groom Creek,and other mineral districts of this type make a Laramide age more probable.

REFERENCES: #120, #185, #194

49

DISTRICT: KIRKLAND


GEOLOGIC SETTING: No detailed description of the Kirkland district is available. TheYavapai County geologic map (Az. Bur. Mines, 1951) shows a north-northeast-trendingband of Yavapai Series schists hosting the district. The district has lithophilicaccessory minerals including W, Mo, F, Hg, and Fe. Keith and others (1983a,b) statethat mineralization is found in northwest- and northeast-trending rhyolite porphyrydikes.

AGE: There is insufficient geologic data for this district to make an intelligent andmeaningful age determination. A Laramide or mid-Tertiary age is possible.

REFERENCES: #17

DISTRICT: MARTINEZ


GEOLOGIC SETTING: The Congress Mine of the Martinez district is Yavapai County'spremier middle Tertiary gold producer. Proterozoic porphyritic granite is thepredominant rock type of the district. Many of the orebodies are related toeast-west-trending, shallowly dipping andesite (microdiorite?) dikes of presumedMiocene age. Gold is mostly in quartz veins with auriferous pyrite, auriferousgalena, and chalcopyrite.

AGE: Copper-gold mineralization related to andesite (microdiorite?) dikes in theMartinez district closely resembles microdiorite-related mineralization of knownmid-Tertiary age in the nearby Harcuvar Mountains.

REFERENCES: #54 #89 #114 #185 #194

DISTRICT: MOUNT UNION

PRODUCTION: Au, Cu, Ag, Pb, Zn

GEOLOGIC SETTING: The Mount Union district bedrock geology is comprised of GreenGulch volcanics and 1760 m.y.-old granodiorites, both of which are intruded by lessextensive Laramide(?) rhyolites thought to be related to the Laramide Walker stock.The foliation in the Yavapai Series trends NI0E to N45E. At the Superior (Chase)property mineralization is in veins which, along with rhyolite dikes, parallelfoliation. In general, however, mineralization does not follow the regionalfoliation, but is related to the rhyolite dikes. Ore minerals are chalcopyrite,galena, sphalerite, and argentiferous galena in quartz veins with specularite andpyrite gangue. The Mount Union mineral district is similar to Hassayampa, Groom Creek,and Walker districts.

AGE: Keith and others (1983a,b) favor a middle Tertiary age based on similarity ofelement suite to other mid-Tertiary districts. E. DeWitt (written comm.) favors a

50

Laramide age because of the local northeast trend of orebodies and by the inferredassociation with the Laramide Walker granodiorite.

REFERENCES: #7, #185, #194

DISTRICT: PECK

PRODUCTION: Ag, Pb, Cu, Au

GEOLOGIC SETTING: Peck has the largest historic Ag production of Yavapai County'smiddle Tertiary districts. The regional geology is characterized by an intenselyfolded sequence of Precambrian metavolcanics and granitoids. Ore deposits areassociated with northeast-trending, steeply-dipping fault zones and Laramide(?)rhyolite porphyry dikes. Reported ore mineralogy is native silver, cerargyrite,tetrahedrite, argentiferous galena, and chalcopyrite.

AGE: There is no definitive data for the age of the Peck district. The northeasttrend of the veins and probable association with Laramide(?) dikes provide persuasivearguments for a Laramide age. However, the extremely high silver content of the oresargues for a mid-Tertiary age of mineralization. At this time either age isconsidered possible.

REFERENCES: #2, #3, #8, #10, #15, #185

DISTRICT: RED PICACHO


GEOLOGIC SETTING: The Red Picacho district is an inlier of Tertiary rhyolites anddacites surrounded by Yavapai Group schists that contain the extensive White Picachopegmatite district. The Red Picacho deposits are in northwest~trehdihgquartz veinswithin the middle Tertiary volcanics. Native gold is the stated ore mineral withcalcite as gangue. The southern portion of the district hosts uranium and tungsten aswell as gold mineralization; the host rock for these deposits is hornblende gneisswith scheelite, torbernite, schroeckingerite, and chrysocolla.

AGE: The probable mid-Tertiary age of the silicic volcanics, and the northwest trendof the veins both favor a mid-Tertiary age for this district.

REFERENCES: #17, #94, #123, #185

DISTRICT: RICH HILL


GEOLOGIC SETTING: The Rich Hill district is segmented and the southern portionoverlaps the Congress Precambrian tungsten district. The most important mines,however, are in a cluster located 7 km south of Yarnell, AZ. The country rockconsists of undifferentiated Precambrian Yavapai Series and Tertiary(?) diorite and

51

andesite dikes. Mineralization is in low-angle quartz veins and is frequentlyassociated with andesite and rhyolite dikes. Native gold t galena t and pyritepredominate. Tellurides are reported at the Bee Hive Mine.

AGE: The exact age of Rich Hill is poorly constrained. The ores of the Rich Hilldistrict are mineralogically similar to those of the Congress mine in the Martinezdistrict. This similarity along with the presence of low-angle structures hosting theore suggest a mid-Tertiary age. Keith and others (1983a tb) suggest that theassociated dikes are microdiorite dikes t of probable mid-Tertiary age t supporting amid-Tertiary age for mineralization.

REFERENCES: #78 t #89 t #162 t #185 t #186 t #194

DISTRICT: SHEA

PRODUCTION: Agt AUt Cu

GEOLOGIC SETTING: The Shea District is in the Yavapai Series metamorphics whichinclude the Shea basalt t the Deception rhyolite t and unnamed granite porphyry dikes.Ore bodies trend east-west and range up to 2 m in width in low-angle structures. Theore includes pyrite t tetrahedrite t chalcopyrite t arsenopyrite t galena t and nativesilver. Bull quartz is the predominent gangue with lesser siderite and ankerite. Theveins also produced several tons of barite. Lindgren (1926) notes extensive chlorite tepidote t sericite and quartz alteration in the wallrocks.

AGE: The high silver grades and low-angle structures are suggestive of a mid-T~~tiary

age.


DISTRICT: TIP TOP

PRODUCTION: Agt AUt CUt Pb

GEOLOGIC SETTING: The Tip Top deposits are characterized by northeast-striking veinscutting Precambrian granite and schist. The veins consist of quartz t chalcedonYt combquartz t and pyrite; ore minerals include wolframite t arsenopyrite t sphalerite t andgalena. The galena is argentiferous. In the oxidized portions of the veins rubysilvers and silver chlorides are found in high grade pockets. Within 150 m of themajor workings are north-northeast-striking rhyolite porphyry dikes t thought to begenetically related to the ores.

AGE: Keith and others (1983a tb) ascribe a mid-Tertiary age to these dikes anddeposits. The rhyolite porphyry dikes responsible(?) for the mineralization are as yetundated t however their strike direction (NNE) is characteristic of the Laramidetectonic regime (Rehrig and Heidrick t 1976). A Laramide age is further indicated by a67 m.y. K-Ar age on sericite (C. Kortemeir t 1985 t pers. comm.).


52

DISTRICT: WRKEY CREEK

PRODUCTION: Ag, Pb, Au, Cu, Zn

GEOLOGIC SETTING: The Turkey Creek deposits are small and poorly known. Thenorth-south-striking, steeply-dipping veins are hosted by upper Spud Mountainvolcanics and Crooks Canyon granodiorite. The high-grade zones are oxidized andconsist of native silver and silver chlorides with quartz. Quartzgalena-sphalerite-tetrahedrite-chalcopyrite comprise the lower unoxidized levels ofthe veins.

AGE: Keith and others (1983a,b) ascribe a mid-Tertiary age for this district.Anderson and Blacet (1972) show no Tertiary magmatic rocks in the region except forthe metallogenically barren Hickey Basalts. A Laramide quartz latite porphyry plug iswithin several miles of the Turkey Creek district (Anderson and Blacet, 1972), yetthere is no demonstrable relationship between this plug and the ores. The age of thisdistrict is considered to be unknown.


DISTRICT: WALNUT GROVE

PRODUCTION: Pb, Ag, Au, Cu, Zn

GEOLOGIC SETTING: No detailed description is available of the Walnut Grove district.The major rock types present are Precambrian Yavapai Series and granitoids. Themineralization is in quartz veins with cuprite, azurite, malachite, chalcopyrite andpyrite. The veins are related to northeast-trending silicic dikes.

AGE: The age of Walnut Grove is highly uncertain. E. DeWitt (written comm.) suggestsa Laramide age, while Keith and others (1983a,b) favor a middle Tertiary age for theveins and replacements.

REFERENCES: #17, #54, #89, #185, #186

YUMA COUNTY

DISTRICT: BLACK TOP

PRODUCTION: Mn

GEOLOGIC SETTING: Pyrolusite and psilomelane in discontinuous shoots, stringers, andpods. Gangue is composed of quartz, calcite and wallrock fragments. The irregularore horizons are along fracture veins cutting late Oligocene to early Miocenecalc-alkaline andesites and rhyodacites.

AGE: Gutman (1982) has dated the volcanic rocks of the Castle Dome Mountains. Theages range from 25.0 to 20.39 m.y.B.P., hence the volcanic rocks hosting the Black Topmanganese deposits are of mid-Tertiary age. We favor a mid-Tertiary age for the

53

mineralization.

REFERENCES: #69, #80, #103, #190

DISTRICT: CASTLE DOME

PRODUCTION: Pb, Ag, Au, Cu, Zn

GEOLOGIC SETTING: Argentiferous galena-fluorite-barite fissure veins in greenschistfacies(?), Mesozoic, fine-grained, clastic metasedimentary rocks, closely associatedwith dacite porphyry and rhyolite porphyry dikes. The veins are in a wide, steeplydipping fault zone which cuts the metasediments and dikes. The veins may becontinuous for considerable distances, but thicken from one meter to greater thanthree meters in width. Outcropping veins consist of fluorite, calcite, and baritewith local gypsum and minor quartz. Oxide zones contain cerussite, anglesite, and leadoxide. At depth, galena occurs as sheet-like masses or irregular vein-like bodiesscattered through a gangue of banded, toarsely~crystallirte,varicolored fluorite,calcite, bladed to massive barite, and quartz. Wallrocks show pronouncedsilicification, carbonatization, and sericitization, with weak chloritization anddisseminated pyrite.

AGE: Mineralization is spatially and temporally related to northwest-trending dikes.These dikes have been dated at 19.0 and 20.4 m.y.B.P. (Logan and Hirsch, 1982).

REFERENCES: #103, #122, #194

DISTRICT: HOVATTER

PRODUCTION: Mn

GEOLOGIC SETTING: Pyrolusite and psilomelane mixed with calcite and brecciatedwallrocks in stringers, pods, and overlapping lenses, or irregular veins and flattabular bodies within a large shear zone in middle Tertiary andesite flows.

AGE: The deposits are hosted by mid-Tertiary volcanic rocks, and therefore are middleTertiary or younger. A middle Tertiary age is favored because this was a time of

i widespread magmatism.


DISTRICT: KOFA


GEOLOGIC SETTING: Spotty, but often high-grade, fine-grained, gold and silvermineralization in quartz-calcite gangue, forming lenses within brecciated wallrock,and in fissure veins cutting Tertiary rhyolitic to dacitic ash-flow tuffs and Mesozoicschist or slate. Northwest-striking, southwest-dipping dikes of silicic tointermediate composition are associated with zones of mineralization. Minor copper

54

AGE:1982).

f!

and lead sulfide' mineralization is present with locally important amounts of manganeseoxides and fluorite. Wallrocks are strongly silicified.

The volcanic pile yielded K-Ar dates of 19.5 to 17.3 m.y.B.P. (Dahm and Hankins,The associated dikes are thought to be of the same age.

REFERENCES: #44, #98, #103, #190

DISTRICT: LAGUNA


GEOLOGIC SETTING: The Laguna district consists of sporadic gold and silver with minorcopper mineralization in lenticular and brecciated quartz veins. Gangue mineralogyconsists of iron oxides, manganese oxides, siderite, gypsum, and fault gouge. Theveins appear to occupy fault zones in Mesozoic schists. The wallrocks are silicifiedand seric.itiZed. Loca.lly proximal to the veins are pods of aplitic granite. Therelationship between the granite pods and mineralization is unclear.

AGE: This district is insufficiently known to determine a verifiable age. Keith andothers (1983a,b) suggest a mid-Tertiary or Paleocene age.


DISTRICT: NEVER SWEAT

PRODUCTION: Ag, Cu, Pb, Au

GEOLOGIC SETTING: Irregular shoots of argentiferous galena with barite, minorfluorite, silver chlorides and sulfides, and oxidized copper mineralization. Theseshoots are in lensing veins and brecciated fault zones cutting Mesozoic schist.Spatially associated bodies of andesitic to rhyolitic dikes are present.

AGE: Keith and others (1983a,b) propose a mid-Tertiary age for this district becauseof its gross similarities with the dated Castle Dome district.

t REFERENCES: 11103, 11190

DISTRICT: SHEEP TANKS


GEOLOGIC SETTING: Strong faulting and fracturing are characteristic throughout thedistrict. Rhyolitic flows lie unconformably beneath thick dacitic flows. Irregularmasses, sills, and dikes of diorite porphyry intrude and cross-cut both the rhyoliteand dacite. Intensely silicified and iron and manganese stained breccia unconformablyoverlie the rhyolite and diorite porphyry and lie in apparent fault contact with thedacite. The brecciated zone is locally cemented and filled by quartz-carbonate veins.

The veins consist of irregular masses and streaks of limonite, pyrolusite, quartz,

55

i

I)

and calcite, and are cut by barite veins. Shoots of gold and silver mineralization,locally with chrysocolla and secondary lead minerals, are found lensing within theveins. The wallrocks are intensely silicified, chloritized and sericitized.

AGE: Mineralization is hosted by volcanics that yield middle Tertiary ages in thenearby Kofa and Eagle Tail Mountains (Cousins, 1984).

REFERENCES: #38A, #38B, #103, #190

56

TABLE 2. MID-TERTIARY MINERAL DISTRICTS BY LITHOTECTONIC ASSOCIATION

VOLCANO-PLUTONIC COMPLEXES

1!

KNOWN OR PROBABLE ASSOCIATION

CALIFORNIA, COCHISEMIDDLE PASS, COCHISEPEARCE, COCHISETEVISTON, COCHISEARAVAIPA, GRAHAMRATTLESNAKE, GRAHAMSTANLEY, GRAHAMASH PEAK, GREENLEETWIN PEAKS, GREENLEENEW WATER, LA PAZNORTHERN PLOMOSA, LA PAZCAVE CREEK, MARICOPAGOLDFIELDS, MARICOPAARTILLERY PEAK, MOHAVEEL DORADO PASS, MOHAVEMINNESOTA, MOHAVEOATMAN, MOHAVEVIRGINIA, MOHAVEWHITE HILLS, MOHAVEBABOQUIVARI, PIMABEN NEVIS, PIMAMARTINEZ CANYON,PINALMINERAL HILL, PINALRANDOLPH, PINALSILVER REEF, PINALSUPERSTITION MTNS., PINALAUSTERLITZ-YELLOW JACKET, SANTA CRUZBLACK CANYON, YAVAPAIPECK, YAVAPAICASTLE DOME, YUMAKOFA, YUMA

57

POSSIBLE ASSOCIATION

RUCKER CANYON, COCHISEPIKES PEAK, MARICOPALEAD PILL, MOHAVEPILGRIM, MOHAVEUNION PASS, MOHAVEMAMMOTH, PINALSLATE, PINALRED PICACHO, YAVAPAINEVERS

MICRODIORITE DIKES


CUNNINGHAM PASS, LA PAZHARCUVAR, LA PAZHARQUAHALA, LA PAZLA CHOLLA, LA PAZSOUTHERN PLOMOSA, LA PAZSALT RIVER MTNS., MARICOPAMARTINEZ, YAVAPAIRICH HILL, YAVAPAI


RED PICACHO, YAVAPAIELLSWORTH, LA PAZLITTLE HARQUAHALA, LA PAZBIGHORN, LA PAZ

DETACHMENT RELATED


ALAMO, LA PAZCIENEGA, LA PAZCLARA, LA PAZMAMMON, LA PAZMIDWAY, LA PAZMOON MTNS., LA PAZPLANET, LA PAZSWANSEA, LA PAZCLEOPATRA, MOHAVECYCLOPIC, MOHAVEOWENS, MOHAVERAWHIDE, MOHAVERINCON, PIMABULLARD, YAVAPAI

STRATABOUND


ARTILLERY, MOHAVEBURMISTER, YAVAPAIDATE CREEK, YAVAPAI

58


LINCOLN RANCH, LA PAZTRIGO MTNS, LA PAZAGUILA, MARICOPASAN DOMINGO, MARICOPAPICACHO, PINAL


LINCOLN RANCH, LA PAZBLACK BURRO, MOHAVE

35·

... /PEARCE ~.,PASS':::::":,,... CALIFORNIAk:--°

RUCKER CANYON"-o

Associated

in Arizona

o Flogstoff

:-==-SABoaUIVAAI

Volcano - Plutonic

Mineral Districts

/EL DORADO PASS

, '-WHITE" HILLS

,~VIRGINIA/1PILGRIM

\ Ie:5,,~UN10N PASS

-t~OATMAN

1130

112 0 1110 110037°,-J-------l.-----L--_--,L L --l ---l.1_-,-,_.1- +-' -'- 1_370

j II

!,J)

/~

.J./

~\

(I

I-~I ,

I '----,'--L

I

L-_-1'i I

ARTILLERY PEAK\ ! I iCEAD PILL-----., '_ I ~\S-~ I

..~ . / ~"'- I- v- ... / I PECK __ .. 1~8LACK CANYON "'Vl

I ~ I i(-NORTHERN I'--------..4 /-----S 1-----

1

'I

PLOMOSA REO PICACHO...--- -___.' • <ii' ")

'\; I' PIKES PEAK~: .'. '<CAVE CREEK, 'I I' .{~r-;''',' GOLDF.'ELD, '\,r\ I--!.,/r

'NEW WATER I \ '_

/- --, J 0 Phoenix r~---, /,_/-1t L- ~- --- .,.-RANDOLPH r./

IKOFA~ ~SHEEP TANKS ---SUPERSTITION MTN$.

---I ~~m~LEO:"::ER J1

" j~'~·;'~"""!;-"'·\:\2ie"..",,, _,,,I I ~/ARAVArPA TWIN ,PEAKS-C

I I MAMMOTH-'" I ASH PEAK~I I 'f~SILVER REEF ~ )

f-- J I:l_~_S~A_TE__ ---------i '-RATTLESNAKE (,

I ,----------I TEVISTON---dI

I 0 Tucson

I I

.-BEN NEvIS I32 0

' ........ MINNESOTA

'0

34 0

20 30 40 Milts

'=='==1=1="===,,

J Probable or known relationship to volcano-plutonic complexes.

«) Possible relationship to volcano- plutonic complexes.

Figure 2

59

32'

35'

II

L_

1,

II

II

!I

II

I

o Flagstaff

Microdiorite-Dike Associated

Mineral Districts in Arizona

I32'

35

litO 110037',----'--__---'- --7-,-----l------l------l1----,----l -1' ~ 1-370

/I

)~)

/~J./

~\

(I

!-~,

i "'"--"'--L,

! L_--'l

I 'i j

, I'i r~~,-,,- I

--...1'MARTINEZ f " '--""'/I-V-,/" I \, ';>R'CH HILL I '0"\

,.t. ~ ,

.. ~---__ /-------~ L ,~

' ~'_'-CUNN'NGHAM PASS ~ r ~?~~HARCUVAA ~REDP~~HO .

ELLSWORTH 'If I' I ,_

• ~~0.. ' O~'G HORN \ I r~/' "~ LITTLE HARQUAHALA '\...1'\ I r"'"

LA CHOLLA ... SOUTHERN PLOMOSA I~,/r--, J 0 Phoenix r---l'----- r-----\ r'----SALT RIVER MTNS_~ I

i i ~,--~ \ ~33' --. ! \/1 \

-----__-1__" -~--------~ i,-------

o Tucson !I,II1---1

-~ i,

, Probable or known relationship ta micradiarite dikes"

10 20 30 400==±=1='~=±===II M! Ie$

\} Passible

Figure 3

60

35"

113 0

I

Detachment- Fault Associated

Mineral Districts in ArizonaI

II

II

L_

o Flagstaff

I II i eo PlcAcHa I

>----------------------------

Io Tucson

37"

o 10 2:0 30 40 MiltsL I

.) Proboble or known relationship to detachment faults.

A Possible relationship to detachment faults.

Figure 4

61

RINCON-#

32"

TABLE 3. PRESENT VALUE OF PRODUCTION FROMMID-TERTIARY MINERAL DISTRICTS

Production data for this compilation are taken from Keith andothers (1983a). Metal prices, listed below, used to calculatepresent value of production are from Engineering & MiningJournal's (March, 1984) average annual metal prices. The pricesused are the 1983 average price, except where otherwise indicated.All values are rounded-off to the nearest one hundred dollars.

COPPER: $O.78/1b; domestic refinery

GOLD: $423.83/oz; Handy and Harmon, N.Y.

LEAD: $O.22/1b; primary delivered

*MANGANESE: $O.70/1b; regular 99.5 %

MOLYBDENUM: $3.64/1b; dealer oxide

SILVER:

TUNG STEN:

URANIUM:

VANADIUM:

ZINC:

*

$11.44/oz; Handy and Harmon, N.Y.

$64.48/stu W0 3 ; 65% min GSA 12/15/83

$17.50/1b U3

08

; NUEXCO's exchange value 2/29/84

$3.50/1b V2 0 5 ; 98% fused f.o.b. N.Y. 5/15/81

$O.41/1b; high grade delivered

Manganese production data based on pounds delivered toovernment urchasing depots at Deming, New Mexico, and Wenden,

Arizona, and do not meet the gra e cr ter on. 0 ca cu a epresent value we have assumed a 25% grade for this material.

62

1j

MID-TERTIARY MINERAL DISTRICT PRESENT VALUE TOTALS:

Au: $1,888,769,800Ag: $508,786,900Mn: $218,313,900Cu: $98,261,100Zn: $52,019,400Pb: $50,519,250Mo: $14,357,800V: $8,928,300U: $681,400W: $600

GRAND TOTAL OF PRESENT VALUE FOR MID-TERTIARY MINERAL DISTRICTS:

$2,840,638,450

68

TABLE 4. GRADES OF MID-TERTIARY MINERAL DISTRICTS

The following table is a compilation of grade statistics formid-Tertiary age mineral districts in Arizona. The grades werecalculated by standard means from U.S. Bureau of Mines statistics;the data is accurate to 1981, the last year USBM statistics werereported. Values of <0.01 and <0.001 indicate that the listedmetal was produced but in insignificant amounts, while a value of0.00 indicates that there is no recorded production for the listedmetal.

The values for Cu, Pb, Zn, and Mo are in weight perc~nt,

those for Ag and Au are in ounces per ton.

COCHISE COUNTY

DISTRICT Cu Pb Zn Mo Ag Au

APACHE PASS 0.01 2.37 0.00 0.00 1 .011 0.916CALIFORNIA 0.55 13.56 1. 93 0.00 4.485 0.003MIDDLE PASS 1. 26 0.20 4.37 <0.01 1.132 0.004PEARCE <0.01 <0.01 <0.01 0.00 5.17 a 0.053RUCKER CANYON 0.00 0.00 0.00 0.00 22.897 0.034TEVISTON o•18 1.16 0.00 0.00 1 .641 0.821SWISSHELM 0.10 12.72 0.23 0.00 7 .317 a •122YELLOWSTONE a .27 2.33 0.00 0.00 1 .90 3 0.742

GRAHAM COUNTY

DISTRICT

ARAVAIPARATTLESNAKESTANLEY

GREENLEE COUNTY

DISTRICT

ASH PEAKTWIN PEAKS

Cu

0.330.005.25

Cu

<0. a10.34

Pb

6.060.00

24.02

pb

<0.01o.37

Zn

4.900.060.00

Zn

0.000.00

69

Mo

0.000.000.00

Mo

0.000.00

Ag

1 .2405 •a146.796

Ag

6.6564.708

Au

0.0150.3960.132

Au

0.026a .216

LA PAZ COUNTY

DISTRICT Cu Pb Zn Me Ag Au

ALAMO 2.77 1.13 0.00 0.00 0.471 0.117BOUSE 7 .41 0.00 0.00 0.00 0.296 a .841CIENEGA 4.49 0.00 0.00 0.00 0.084 0.629CINNABAR 3.72 0.00 0.00 0.00 2.378 a •110CLARA 4.69 0.00 0.00 0.00 0.035 <0.001CUNNINGHAM PASS 8.77 0.02 0.00 0.00 0.297 0.463ELLSWORTH 2.59 0.05 0.00 0.00 1.000 a . 118HARCUVAR 2.86 0.00 0.00 0.00 0.217 0.278HARQUAHALA 0.08 <0.01 0.00 0.00 0.350 0.124LA CROLLA 6.62 0.00 0.00 0.00 9.631 1 .204LA PAZ 0.07 0.01 0.00 0.00 0.095 0.217LITTLE HARQUAHALA 0.02 0.05 0.00 0.00 0.566 0.901MAMMON 5.17 0.00 0.00 0.00 0.169 0.071MIDDLE CAMP 0.01 7.26 0.00 0.00 0.255 0.276MIDWAY 2. 20 0.00 0.00 0.00 0.164 0.210MOON MOUNTAINS 0.00 0.00 0.00 0.00 2.667 0.333NEW WATER 0.30 0.90 <0.01 0.00 34.294 0.022NORTHERN PLOMOSA 2.31 a .17 0.00 0.00 0.977 0.677PLANET l.00 0.00 0.00 0.00 <0.001 <0.001SILVER <0.01 1.19 <0.01 0.00 12.753 <0.001SOUTHERN PLOMOSA 6.60 0.07 0.00 0.00 7.487 0.295SWANSEA 2.43 0.00 0.00 0.00 0.061 <0.001

MARICOPA COUNTY


AGUILA • 17 2.75 0.00 0.00 1.090 0.397BIG HORN 0.08 0.02 0.00 0.00 0.073 0.225CAVE CREEK 0.56 <0.01 0.00 0.00 0.519 0.496GOLDFIELDS 0.00 0.00 0.00 0.00 2.529 0.443OSBORNE a .91 3 .71 <0.01 0.00 2.316 0.144

j PAINTED ROCK 6.69 14.39 0.00 0.00 4.511 0.047PIKES PEAK 0.25 0.16 0.00 0.00 0.512 0.551RED PICACHO 6.47 0.00 0.00 0.00 0.793 0.389RELIEF 0.00 0.00 0.00 0.00 0.021 0.310SAN DOMINGO 2.44 0.02 0.00 0.00 0.683 a .512SALT RIVER MTNS. 0.09 0.00 0.00 0.00 0.327 0.459SUNRISE 0.09 0.00 0.00 0.00 0.159 0.582VULTURE 0.02 a .12 0.00 0.00 a .273 a .351WEBB 3 .7 1 0.38 0.00 0.00 0.485 0.137WINIFRED 0.03 <0.01 0.00 0.00 0.093 0.231

70

MOHAVE COUNTY


ARTILLERY 1. 46 <0.01 0.00 0.00 1 .323 0.018BUCK MOUNTAINS <0.01 0.55 0.00 0.00 0.409 o .341CEDAR VALLEY 0.02 0.00 0.00 0.00 5.167 0.556CHEMEHUEVIS 0.02 0.87 <0.01 0.00 1 .807 0.628CLEOPATRA 1.19 <0.01 0.00 0.00 0.580 0.088EL DORADO PASS 0.02 0.03 0.00 0.00 0.847 o.211EMERALD ISLE 0.78 0.00 0.00 0.00 <0.001 <0.001GREENWOOD 0.01 0.04 0.00 0.00 0.394 0.631LEAD PILL 0.96 13.96 0.00 0.00 1 .535 0.365McCONNICO <0.01 0.00 0.00 0.00 0.079 0.156McCRACKEN <0.01 0.88 0.01 0.00 4.038 <0.001MINNESOTA 0.07 0.02 0.00 0.00 0.878 0.414OATMAN <0.01 <0.01 0.00 0.00 0.296 0.501OWENS 0.11 3.95 <0.01 0.00 13.038 0.133PILGRIM 0.00 0.00 0.00 0.00 0.258 0.170PINE PEAK 0.02 0.32 0.42 0.00 0.466 0.039RAWHIDE 0.75 18.37 1. 6 2 0.00 11.475 0.054UNION PASS 0.00 0.00 0.00 0.00 0.475 0.163VIRGINIA <0.01 <0.01 0.00 0.00 0.232 0.232WHITE HILLS <0.01 0.02 0.00 0.00 3.119 0.017YELLOW JACKET 0.31 0.02 7 • 11 0.00 1 .802 0.037

PIMA COUNTY


ARIVACABABOQUIVARI 0.01 <0.01 0.00 0.00 2.322 0.194BEN NEVIS 0.46 0.04 0.00 0.00 450.202 0.761CERRO DE FRESNAL o .11 0.00 0.00 0.00 15.868 0.647OCEANIC <0.01 0.01 0.00 0.00 0.270 0.403RINCON 3.28 0.19 0.00 0.00 2 .411 0.570

7 1

PINAL COUNTY


COPPER BUTTE 2.94 <0.01 0.00 0.00 0.030 <0.001CRESCENT 14.83 0.00 0.00 0.00 23.500 0.167GREENBACK" 0.13 0.00 0.00 0.00 3.808 o.129MAMMON 0.05 0.00 0.00 0.00 o•163 1 .425MAMMOTH 0.10 1. 25 0.82 0.04 0.313 0.066MARTINEZ CANYON o•19 4.94 <0.01 0.00 6.982 0.002MINERAL HILL 0.14 0.07 <0.01 0.00 12.724 0.010MINERAL MOUNTAIN 0.49 6.51 0.94 0.00 0.844 0.085OWL HEAD 1. 27 0.00 0.00 0.00 5.039 0.025PICACHO 0.97 0.00 0.00 0.00 0.540 0.177RANDOLPH 0.41 3.66 0.00 0.00 13.492 0.096SILVER REEF 0.07 0.08 0.00 0.00 10.554 0.006SLATE <0.01 0.02 0.00 0.00 0.470 0.003SU PERSTITION MTNS. 0.56 0.00 0.00 0.00 0.775 0.307TABLE MOUNTAIN 8.00 0.00 0.00 0.00 <0.001 0.193WOOD CAMP CANYON 1.09 0.00 0.00 0.00 2.941 0.002

SANTA CRU Z COUNTY


CAVE CREEK 0.86 <0.01 0.00 0.00 4.145 0.008ORO BLANCO 0.22 3.23 2.71 0.00 4.916 0.049YELLOW JACKET 0.03 0.00 0.00 0.00 1 .578 1 .252

72

YAVAPAI COUNTY

DISTRICT Cu Ph Zn Mo Ag Au

BATTLE FLAT 0.39 0.25 0.09 0.00 33.032 0.032BLACK CANYON 0.05 0.68 0.04 0.00 3.584 0.124BLACK ROCK 0.61 o.10 0.00 0.00 2.283 0.259BULLARD 1. 77 0.00 0.00 0.00 0.347 0.210CASTLE CREEK 2. 66 0.89 0.00 0.00 3.137 0.475CROSBY 0.09 0.04 0.00 0.00 0.441 0.515FRENCH GULCH 0.02 <0.01 0.00 0.00 0.125 0.228GROOM CREEK 0.56 0.03 0.06 0.00 5.671 0.271HASSAYAMPA 0.65 2.13 1. 27 0.00 6.380 0.522HUMBUG 0.93 0.67 0.00 0.00 1 .662 0.375KIRKLAND 0.04 0.05 0.00 0.00 0.317 0.525MARTINEZ <0.01 <0.01 0.00 0.00 0.375 0.348MOUNT UNION 0.77 1. 35 0.32 0.00 3.924 0 703PECK 0.05 0.72 0.00 0.00 88.789 0.005RED PICACHO 0.62 0.01 0.00 0.00 0.817 0.574RICH HILL <0.01 0.06 0.00 0.00 0.257 0.270SHEA 1.88 0.00 0.00 0.00 32.902 o•137SILVER MOUNTAIN 0.78 0.70 0.00 0.00 1 .823 1.112TIP TOP 0.02 0.05 0.00 0.00 67.348 0.347TURKEY CREEK 0.09 2.55 <0.01 0.00 5.487 0.080WALNUT GROVE 0.32 4.71 0.27 0.00 5.259 0.111

YUMA COUNTY

DISTRICT Cu Ph Zn Mo Ag Au

CASTLE DOME 0.02 3.76 <0.01 0.00 1 .652 0.01KOFA <0.01 0.00 0.00 0.00 o•116 0.314LAGUNA o.01 0.00 0.00 0.00 0.140 0.342NEVERSWEAT 3.09 9.82 0.00 0.00 6.421 0.538SHEEP TANKS <0.01 0.00 0.00 0.00 1 .959 0.359

!

73

districtWeightedounces

TABLE 5. GRADES OF ORE BY LITHOTECTONIC ASSOCIATION

The average grades are arithmetic means of the individualgrades, and hence subject to bias by an anomalously high or low value.grades are calculated by summing the total production for each metal inor pounds and dividing by the total ore produced for each lithotectonicassociation. Cu, Pb, Zn, and Mo grades are in weight percent, while those forAg and Au are in ounces per ton.

74

REFERENCES

1. Acker, C. J., 1958, Geologic interpretation of a siliceous breccia inthe Colossal Cave area, Pima County, Arizona: Tucson, Universityof Arizona, MS thesis, 50 p.

2. Anderson, C. A., 1950, Lead-zinc deposits, Bagdad area, YavapaiCounty, Arizona, in Part 1 of Arizona zinc and lead deposits:Arizona Bureau of~ines Bulletin 156, p. 122-138.

3. 1969, Copper, in Mineral and water resources of Arizona:Arizona Bureau of Mines Bulletin 180, p. 117-156.

4. 1972, Precambrian rocks in the Cordes area, Yavapai County,Arizona: U.S. Geological Survey Bulletin 1345, 36 p.

5. Anderson, C. A., and Blacet, P. M., 1972a, Precambrian geology of thenorthern Bradshaw Mountains, Yavapai County, Arizona: U.S.Geological Survey Bulletin 1336, 82 p.

6. 1972b (1973), Geologic map of the Mayer Quadrangle, YavapaiCounty, Arizona: U.S. Geological Survey Geologic Quadrangle MapGQ-996, scale 1:62,500.

7. 1972c (1973), Geologic map of the Mt. Union Quadrangle, YavapaiCounty, Arizona: U.S. Geological Survey Geologic Quadrangle MapGQ- 997, scale 1:62,500.

8. Anderson, C. A., Blacet, P. M., Silver, L. T., and Stern, T. W.,1971, Revision of Precambrian stratigraphy in the Prescott-Jeromearea, Yavapai County, Arizona: U.S. Geological Survey Bulletin1324-C, p. C1-C16.

9. Anderson, C. A., and Creasey, S. C., 1967, Geologic map of the MingusMountain Quadrangle, Yavapai County, Arizona: U.S. GeologicalSurvey Geologic Quadrangle Map GQ-715, scale 1:62,500.

10. Anderson, C. A., and Silver, L. T., 1976, Yavapai series-a greenstonebelt: Arizona Geological Society Digest v. 10. p. 13-26.

11. Anderson, P., and Guilbert, J. M., 1979, The Precambrianmassive-sulfide deposits of Arizona: A distinctepoch and province, in Ridge, J. D., ed., Papers on mineraldeposits of western North America: Nevada Bureau of Mines andGeology Report 33, p. 39-48.

12. Anderson, R. E., Longwell, C. R., Armstrong, R. L., and Marvin, R.F., 1972, Significance of K-Ar ages of Tertiary rocks from theLake Mead region, Nevada-Arizona: Geological Society of AmericaBulletin, v. 83, no. 2, p. 273-287.

13. Anthony, J. W., Williams, S. A., and Bideaux, R. A., 1977, Mineralogyof Arizona: Tucson, Arizona, University of Arizona Press, 255 p.

14. Arizona Bureau of Geology and Mineral Technology Clippings file:Tucson, Arizona, Arizona Bureau of Geology and MineralTechnology, 85719.

15. Arizona Bureau of Geology and Mineral Technology File data: Tucson,Arizona, Arizona Bureau of Geology and Mineral Technology, 85719.

16. Arizona Bureau of Mines, 1950, Arizona zinc and lead deposits, Part1: Bulletin 156, 114 p.

17. 1958, Geologic map of Yavapai County, Arizona: scale1:375,000.

18. 1959, Geologic map of Cochise County, Arizona: scale 1:375,000.

75

19. Arizona Department of Mineral Resources, 1941, Productionpossibilities of the marginal copper mines in Arizona: Phoenix,Arizona, Department of Mineral Resources, 85007.

20. Balla, J. C., 1972, The relationship of laramide stocks to regionalstructure in central Arizona: Tucson, University of Arizona, PhDdissertation, 132 p.

21. Bancroft, H., 1911, Reconnaissance of the ore deposits in northernYuma County, Arizona: U.S. Geological Survey Bulletin 451, 130p.

22. Banks, N. G., 1980, Geology of a zone of metamorphic core complexesin southeastern Arizona, in Crittenden, M. D., Jr., Coney, P. J.,and Davis, G. H., eds., Cordilleran metamorphic core complexes:Geological Society of America Memoir 153, p. 177-215.

23. Banks, N. G., Docktor, R. D., and Briskey, J. A., 1976, Maps showingmines, mineralization, and alteration in the Tortolita MountainsQuadrangle, Arizona, map A: U.S. Geological Survey Open-FileReport 76-764, map scale 1:62,500.

24. Banks, N. G., Docktor, R. D., Briskey, J. A., Davis, G. H., Keith, S.B., Budden, R. T., Kiven, C. W., and Anderson, P., 1977,Reconnaissance geologic map of the Tortolita MountainsQuadrangle: U.S. Geological Survey Miscellaneous Field StudiesMap MF-864, scale 1:62,500.

25. Barter, C. F., 1962, Geology of the Owl Head mining district, PinalCounty, Arizona: Tucson, University of Arizona, MS thesis, 73 p.

26. Bergquist, J. R., Banks, N. G., and Blacet, P. M., 1978,Reconnaissance geologic map of the Eloy quadrangle, Arizona: U.S.Geological Survey Miscellaneous Field Studies Map MF-990, scale1:62,500.

27. Blacet, P. M., Bergquist, J. R., and Miller, S. T., 1978,Reconnaissance geologic map of the Silver Reef MountainsQuadrangle, Pinal and Pima Counties, Arizona: U.S. GeologicalSurvey Miscellaneous Field Studies Map MF-934, scale 1:62,500.

28. Blacet P. M., and Miller, S. T., 1978, Reconnaissance eolo ic rnao the Jackson Mountain Quadrangle, Graham County, Ar zona: U.S.Geological Survey Miscellaneous Field Studies Map MF-939, scale1:62,500. .

29. Briscoe, J. A., 1967, General geology of the Picacho Peak area:Tucson, University of Arizona, MS thesis, 52 p.

30. Briskey, J. A., Haxel, G., Peterson, J. A., and Theodore, T. G.,1978, Reconnaissance geologic map of the Gu Achi Quadrangle, PimaCounty, Arizona: U.S. Geological Survey Miscellaneous FieldStudies Map MF-965, scale 1:62,500.

31. Bromfield, C. S., and Shride, A. F., 1956, Mineral resources of theSan Carlos Indian Reservation, Arizona: U.S. Geological SurveyBulletin 1027-N, p. 613-619.

32. Budden, R. T., 1975, The Tortolita-Santa Catalina Mountain complex:Tucson, University of Arizona, MS thesis, 133 p.

33. Burnham, C. W., 1959, Metallogenic provinces of the southwesternUnited States and northern Mexico: New Mexico Bureau of Minesand Mineral Resources Bulletin 65, 76 p.

34. Butler, B. S., and Wilson, E. D., 1938, General features, in Part Iof Some Arizona ore deposits: Arizona Bureau of Mines Bulletin

76

145, p.9-25.35. Carpenter, R. H., 1947, The geology and ore deposits of the Vekol

Mountains Pinal County, Arizona: Palo Alto, CA, StanfordUniversity, PhD dissertation, 110 p.

36. Chaffee, M. A., 1964, Dispersion patterns as a possible guide to oredeposits in the Cerro Colorado district, Pima County. Arizona:Tucson, University of Arizona, MS thesis, 69 p.

36A. Cheeseman, R. J., 1974, The geology of the Webb Mountain district,Gila Bend Mountains, Maricopa Countys southwestern Arizona:Flagstaff, Northern Arizona University, MS thesis, 69 p.

37. Clifton, G. C., Buchanan, L. J., and Durning, W. P., 1980,Exploration procedure and controls of mineralization in theOatman mining district, Oatman, Arizona: American Institute ofMining Engineers Preprint 80-143, 69 p.

38. Cooper, J. R., and Silver, L. T., 1964, Geology and ore deposits ofthe Dragoon Quadrangle, Cochise County, Arizona: U.S.Geological Survey Professional Paper 416, 196 p.

38A. Cousins, N., 1972, Relationship of black calcite to gold and silvermineralization in the Sheep Tanks mining district, Yuma County,Arizona: Tempe, Arizona State University, MS thesis, 43 p.

38B. 1984, Gold, silver, and manganese mineralization in the SheepTanks mine area, Yuma County, Arizona in Wilkins, J., Jr., ed.,Gold and silver deposits of the Basin and Range Province, westernU.S.A.: Arizona Geological Society Digest, v. 15, p. 167-174.

39. Creasey, S. C., 1965, Geology of the San Manuel area, Pinal County,Arizona, with a section on Ore deposits by J. D. Pelletier and S.C. Creasey: U.S. Geological Survey Professional Paper 471, 64 p.

40. Creasey, S. C., Jackson, E. D., and Gulbrandsen, R. A., 1961,Reconnaissance geologic map of parts of the San Pedro andAravaipa valleys, south-central Arizona: U.S. Geological SurveyMiscellaneous Field Studies Map MF-238, scale 1:125,000.

41. Creasey, S. C., Jinks, J. E., Williams, F. E., and Meeves H. C.1981 [1982], Mineral resources of the Galiuro Wilderness ancontiguous further planning areas, Arizona: U.S. GeologicalSurvey Bulletin 1490, 94 p.

42. Creasey, S. C., and Krieger, M. H., 1978, Galiuro volcanics, Pinal,Graham, and Cochise Counties, Arizona: U.S. Geological SurveyJournal of Research, v. 6, p. 115-121.

43. Crowl, W. J., 1979, Geology of the central Dome Rock Mountains, YumaCounty, Arizona: Tucson, University of Arizona, MS thesis, 76 p.

44. Dahm, J. B., and Hankins, D. D., 1982, Preliminary geology of aportion of the southern Kofa Mountains, Yuma County, Arizona, inFrost, E. G., and Martin, D. L., eds., Mesozoic-Cenozoic tectonicevolution of the Colorado River region, California, Arizona, andNevada; Anderson-Hamilton volume: San Diego, California,Cordilleran Publishers, p. 459-469.

45. Dale, V. B., 1961, Tungsten deposits of Gila, Yavapai, MohaveCounties, Arizona: U.S. Bureau of Mines Information Circular8078, 104 p.

46. Dale, V. B., Stewart, L. A., and McKinney, W. A., 1961, Tungstendeposits of Cochise, Pima, and Santa Cruz Counties, Arizona: U.S.Bureau of Mines Report of Investigations 5650, 132 p.

77

56.

57 •

iJ

1 58.

59.

47. Davis, G. A., Anderson, J. L.,Frost, E. G., and Shackelford, T. J.,1980, Mylonitization and detachment faulting in the WhippleBuckskin-Rawhide Mountains terrane, southeastern California andWest ern Ariz 0 n a , in Cr i ~ tenden, M. D., Jr. , Coney, P. J. , andDavis, G. H., eds., Cordilleran metamorphic core complexes:Geological Society of America Memoir 153, p. 79-129.

48. Davis, G. H., and Hardy, J. J., Jr., 1981, The Eagle Pass detachment,southeastern Arizona: Product of mid-Miocene listric(?) normalfaulting in the southern Basin and Range: Geological Society ofAmerica Bulletin, v. 92, p. 749-762.

49. Denton, T. C., 1947, Aravaipa lead-zinc deposits, Graham County,Arizona: U.S. Bureau of Mines Reports of Investigations 4007, 14p.

50. Dickinson, W. R., 1984, Reinterpretation of Lime Peak thrust as alow-angle normal fault; implications for the tectonics ofsoutheastern Arizona: Geology, v. 12, p. 610-613.

51. Dings, M. G., 1951, The Wallapai mining district, Cerbat Mountains,Mohave County, Arizona: U.S. Geological Survey Bulletin 978-E,p. 123-163.

52. Docktor, R. D., and Keith, W. J., 1978, Reconnaissance geologic mapof the Vekol Mountains Quadrangle, Arizona: U.S. GeologicalSurvey, Miscellaneous Field Studies Map MF-931, scale 1:62,500

53. Donald, P. G., 1959, Geology of the Fresnal Peak area, BaboquivariMountains, Arizona: Tucson, University of Arizona, MS thesis, 45p.

54. Donnelly, M. E., and Hahn, G. A., 1981, A review of the Precambrianvolcanogenic massive sulfide deposits in central Arizona~hd therelationship to their depositional environment: ArizonaGeological Society Digest, v. 14, p. 11-21.

55. Drewes, H., 1971, Geologic map of the Mount Wrightson Quadrangle,southeast of Tucson, Santa Cruz, and Pima Counties, Arizona: U.S.Geological Survey Miscellaneous Investigations Map 1-614, scale1:48,000.

1972, Cenozoic rocks of the Santa Rita Mountains, southeast of----Tucson, Arizona: U.S. Geological Survey Professional Paper 746,66 p.

1977 (1978), Geologic map and sections of the Rincon Valley.----Quadrangle, Pima County, Arizona: U.S. Geological SurveyMiscellaneous Investigations Map 1-997, scale 1:48,000.

1981, Tectonics of southeastern Arizona: U.S. Geological Survey----Professional Paper 1144, 96 p.

Drewes, H., Watts, K. C" and Klein, D. P., 1983, Mineral resourcepotential map of the Dragoon Mountains roadless area, CochiseCounty, Arizona: U.S. Geological Survey Miscellaneous FieldStudies Map MF-1521-B, scale 1:.

60. Drewes, H., and Bigsby, P. R., 1984, North End roadless area,Arizona, in Marsh, S. P., and others, eds., Wilderness mineralpotential; assessment of mineral-resource potential in U.S.Forest Service lands studied 1964-1984: U.S. Geological SurveyProfessional Paper 1300, v.l, p. 91-93.

61. Drewes, H., and Kreidler, T. J., 1984, Dragoon Mountains roadlessarea, Arizona, in Marsh, S. P., and others, eds., Wilderness

78

mineral potential; assessment of mineral-resource potential inU.S. Forest Service lands studied 1964-1984: U.S. GeologicalSurvey Professional Paper 1300, v.l, p. 59-62.

62. Eaton, G. P., 1970, Altered (pyritized) rocks in San Simon valley,southeastern Arizona, in Geological Survey research 1970: U.S.Geological Survey Professional Paper 700-A, p. A37.

63. Eberly, L. D., and Stanley, T. B., Jr., 1978, Cenozoic stratigraphyand geologic history of southwestern Arizona: Geological Societyof America Bulletin, v. 89, no. 6, p. 921-940.

64. Erickson, R. C., 1968, Geology and geochronology of the Dos CabezasMountains, Cochise County, Arizona, in Titley, S. R., ed.,Southern Arizona Guidebook III: Geological Society of AmericaCordilleran Section, 64th annual meeting, Arizona GeologicalSociety, p. 192-198.

65. 1969, Petrology and geochemistry of the Dos Cabezas Mountains,Cochise County, Arizona: Tucson, University of Arizona, PhDdissertation, 441 p.

66. Fair, C. L., 1965, Geology of the Fresllal Canyon area, BaboquivariMountains, Pima County, Arizona: Tucson, University of Arizona,PhD dissertation, 89 p.

67. Fair, C. L., and Jinks, J, E., 1961, Santa Catalina foothills faultin.the Pontotoc area: Arizona Geological Society Digest. v. 4,p. 131-133.

68. Fair, C. L., and Kurtz, W. L., compilers, 1959, Generalized geologicmap of parts of the Baboquivari, Roskruge, south Comobabi, andArtesia Mountains, Pima County, Arizona, in Volcanic craters ofthe Pinacate Mountains, Sonora, Mexico (rO"ad log): in Heindl, L.A., ed., Southern Arizona Guidebook II: Geological SOciety ofAmerica Cordilleran Section, 55th annual meeting, ArizonaGeological Society Digest, v. 2, p. 256, fig. 57, scale1:200,000.

69. Farnham, L. L., and Stewart, L. A., 1958, Manganese deposits ofwestern Arizona: U.S. Bureau of Mines InformatioIl Circular 7887 p.

70. Farnham, L. L., Stewart, L. A., and Delong, C. W., 1961, Manganesedeposits of eastern Arizona U.S. Bureau of Mines InformationCircular 7990, 178 p.

71. Fowler, G. M., 1951, Oro Blanco or Ruby district, Chapter 5, inPart 2 of Arizona zinc and lead deposits: Arizona Bureau ofMines Bulletin 158, p. 41-49

72. Galbraith, F. W., and Loring, W. B., 1951, Swisshelm district,Chapter 3, in Part 2 of Arizona zinc and lead deposits: ArizonaBureau of Mines Bulletin 158, p. 30-36.

73. Garner, W. E., Frost, E. G., Tanges, S. E., and Germinario, M. P.,1982, Mid-Tertiary detachment faulting and mineralization in theTrigo Mountains, Yuma County, Arizona, in Frost, E. G., andMartin, D. L., eds., Mesozoic-Cenozoic tectonic evolution of theColorado River region, California, Arizona, and Nevada;Anderson-Hamilton volume: San Diego, California, CordilleranPublishers, p. 158-171.

74. Gassaway, J. S., 1972, Geology of the Lincoln Ranch Basin, BuckskinMountains, Yuma County, Arizona: San Diego, CA, San Diego State

79

University, undergraduate thesis, 64 p.75. Gebhardt, R. C., 1931, Geology and mineral resources of the Quijotoa

Mountains: Tucson, University of Arizona, MS thesis, 63 p.76. Gilluly, J., 1956, General geology of central Cochise County,.

Arizona, with sections on age and correlation by A. R. Palmer, J.S. Williams, and J. B. Reeside, Jr.: U.S. Geological SurveyProfessional Paper 281, 169 p.

77. Granger, H. C., and Raup, R. B., 1959, Uranium deposits in theDripping Spring quartzite, Gila County, Arizona: U.S. GeologicalSurvey Bulletin 1046-P, p. 415-486.

78. 1962, Reconnaissance study of uranium deposits in Arizona:U.S. Geological Survey Bulletin 1147-A, p. A1-A54.

79. Gray, D. S., 1982, Geology of the Morgan Butte area, Yavapai County,Arizona: Flagstaff, Northern Arizona University, MS thesis, 115p.

80. Gutmann, J. T., 1982, Geology and regional setting of the Castle DomeMountains, southwestern Arizona, in Frost, E. G., and Martin, D.L., eds., Mesozoic~Cenozoic tectonic eVolution of the ColoradoRiver region, California, Arizona, and Nevada; Anderson-Hamiltonvolume: San Diego, California, Cordilleran Publishers, p.117-122.

81. Hammer, D. F., 1961, Geology and ore deposits of the Jackrabbit area,Pinal County, Arizona: Tucson, University of Arizona, MS thesis,156 p.

82. Harper, H. E., and Reynolds, J. R., 1969, The Lakeshore copperdeposit: Mining Congress Journal, v. 55, no. 11, p. 26-30.

83 • Harrer, C. M., 1964, Re conn a iss an c e of iron resources in Ar iioill a :U.S. Bureau of Mines Information Circular 8236, 204 p.

84. Haxel, G., May, D. J., Wright, J. E., and Tosdal, R. M., 1980;Reconnaissance geologic map of Baboquivari Peak Quadrangle,Arizona: U.S. Geological Survey Miscellaneous Field Studies MapMF-1251, scale 1:62,500.

85. Haxel, G., Wright, J. E., May, D. J., and Tosdal, R. M., 1980,Reconnaissance geology of the Mesozoic and Lower Cenozoic rocksof the southern Papago Indian Reservation, Arizona; a preliminarreport, in Jenney, J. P. ed, Studies in western Arizona: ArizonaGeological Society Digest, v. 12, p. 17-27.

86. Hedlund, D. C., 1979-1980, Data from the York Valley SE Quadrangle,Grant and Hidalgo Counties, New Mexico, and Greenlee County,Arizona: U.S. Geological Survey unpublished data.

87. Heindl, L. A., 1960, Cenozoic geology of the Papago IndianReservation, Pima, Maricopa, and Pinal Counties, Arizona (apreliminary summary): Arizona Geological Society Digest, v. 3, p.31-34.

88. Heindl, L. A., and Fair, S. L., 1965, Mesozoic(?) rocks in theBaboquivari Mountains, Papago Indian Reservation, Arizona: U.S.Geological Survey Bulletin 1194-1, p. 11-112.

89. Hewett, D. F., Callaghan, E., Moore, B. N., Nolan, T. B., Rubey, W.W., and Schaller, W. T., 1936, Mineral resources of the regionaround Boulder Dam: U.S. Geological Survey Bulletin 871, 197 p.

90. Hewett, D. F, and Fleischer, M., 1960, Deposits of the manganeseoxides: Economic Geology, v. 55, no. 1, p. 1-55.

80

91. Hogue, W. G., 1940, Geology of the northern part of the SlateMountains, Pinal County, Arizona: Tucson, University of Arizona,MS thesis, 43 p.

92. Howard, K. A., Goudge, J. W., and John, B. E., 1982, Detachedcrystalline rocks of the Mohave, Buck, and Bill WilliamsMountains, western Arizona, in Frost, E. G., and Martin, D. L.,eds., Mesozoic-Cenozoic tectonic evolution of the Colorado RiverRegion, California, Arizona, and Nevada: San Diego, CA,Cordilleran Publishers, p. 377-392.

93. Howell, K. K., 1977, Geology and alteration of the Commonwealth mine,Cochise County, Arizona: Tucson, University of Arizona, MSthesis, 225 p.

94. Jahns, R. H., 1952, Pegmatite deposits of the White Picacho district,Maricopa and Yavapai County, Arizona: Arizona Bureau of MinesBulletin 162, 105 p.

95. John, B. E., 1981, Reconnaissance study of Mesozoic plutonic rocks inthe Mojave Desert region, in Howard, K. A. and others, eds.,Tectonic framework of the Mojave arid onoran eserts, Californiaand Arizona: U.S. Geological Survey Open-File Report 81-503, p.48-50.

96. Johnson, M. G., 1972, Placer gold deposits of Arizona: U.S.Geological Survey Bulletin 1355, 103 p.

97. Johnston, W. P., 1972, K-Ar dates on intrusive rocks and alterationassociated with the Lakeshore porphyry copper deposit, PinalCounty, Arizona: Isochron/West, no. 4, p. 29-30

98. Jones, E. L., Jr., 1915 (1916), A reconnaissance in the KofaMountains, Arizona: U.S. Geological Survey Bulletin 620-H, p.151-164.

99. Kahle, K., Conway, D., and Haxel, G., compilers, 1978, Preliminarygeologic map of the Ajo 1 x 2 quadrangle, Arizona: U.S.Geological Survey Open-File Report 78-1096, scale 1:250,000.

100. Keith, Stanton, B., 1973, Index of mining properties in CochiseCounty, Arizona: Arizona Bureau of Mines Bulletin 187, 98 p.

101. 1974, Index of mining properties in Pima County, Arizona:Arizona Bureau of Mines Bulletin 189, 156 p.

102. 1975, Index of mining properties in Santa Cruz County, Arizona:Arizona Bureau of Mines Bulletin 191, 94 p.

103. 1978, Index of mining properties in Yuma County, Arizona:Arizona Bureau of Mines Bulletin 192.

104. Keith, Stanley B., Reynolds, S. J., Damon, P. E., Shafiqullah, M.,Livingston, D. E., and Pushkar, P. D., 1980, Evidence formultiple intrusion and deformation within the SantaCatalina-Rincon-Tortolita metamorphic core complex southeasternArizona, in Crittenden, M. D., Jr., Coney, P •. J., and Davis, G.H., eds.,-Cordilleran metamorphic core complexes: GeologicalSociety of America Memoir 153, p. 217-268.

105. Keith, Stanley B., Reynolds, S. J., and Richard, S. M., 1982,Preliminary geologic map of the western Harquahala Mountains,west-central Arizona: Arizona Bureau of Geology and MineralTechnology Open-File Report 82-6, scale 1:12,000.

106. Keith, Stanely B., Gest, D. E., DeWitt, E., Woode-Toll, N., andEverson, B. A., 1983a, Metallic mineral districts and production

81

107 •

108.

109.

110.

111.

112.

113 •

114 •

114 •

116 •

117 •

118.

i 119 •j

}

120.

121.

122 •

in Arizona: Arizona Bureau of Geology and Mineral TechnologyBulletin 194, 58 p., scale 1:1,000,000.

Keith, Stanely B., Schnabel, L., DeWitt, E., Gest, D. E., and Wilt,J., 1983b [1984], Map, description and bibliography of themineralized areas of the Basin and Range Province in Arizona:U.S. Geological Survey Open-File Report 84-0086, 129 p., scale1:500,000.

Keith, W. J., 1976, Reconnaissance geologic map of the San Vicenteand Cocoraque Butte 15' quadrangles: U.s. Geological Surv9YMiscellaneous Field Studies map MF-769, scale 1:62,500.

Keith, W. J., and Theodore, T. G., 1975, Reconnaissance geologic mapof the Arivaca Quadrangle, Arizona: U.S. Geological SurveyMineral Investigations Resources Map MF-678, scale 1:63,360.

Kerns, J. R., 1958, Geology of the Agua Verde Hills, Pima County,Arizona: Tucson, University of Arizona, MS thesis, 69 p.

Keyes, D. R., 1923, Tres Amigos gold veins of Arizona: Pan-AmericanGeologist, v. 39, no. 2, p. 159~160.

Kirkemo, H., Anderson, C. A., and Creasey, S. C., 1965, Ihvestigationof molybdenum in the conterminous United States, 1942-1960: U.S.Geological Survey Bulletin 1182-E, p. E1-E90.

Knight, L. H., Jr., 1970, Structure and mineralization of the OroBlanco mining district, Santa Cruz County, Arizona: Tucson,University of Arizona, PhD dissertation, 172 p.

Koschmann, A. H., and Bergendahl, M. H., 1968, Principalgold-producing districts of the United States: U.S. GeologicalSurvey Professional Paper 610, 283 p.

Krieger, M. H., 1968, Geologic map of Lookout Mountain Quadrangl~,

Pinal County, Arizona: U.S. Geological Survey GeologicQuadrangle Map GQ-670, scale 1:24,000.

Kuhn, T. H., 1938, Childs-Aldwinkle mine, Copper Creek, Arizona, inSome Arizona ore deposits: Arizona Bureau of Mines Bulletin 145,p. 127-130.

Laskey, S. G., and Webber, B. N., 1949, Manganese resources of theArtillery Mountains region, Mohave County, Arizona: U.S.Geological Survey Bulletin 961, 86 p.

Lausen, C., 1931, Geology and ore deposits of the Oatman andKatherine districts, Arizona: Arizona Bureau of Mines Bulletin131, 126 p.

Lemmon, D. M., and Tweto, o. L., 1962, Tungsten in the United Statesexclusive of Alaska and Hawaii: U.S. Geological Survey MineralResources Map MR-25, scale 1:3,168,000.

Lindgren, W., 1926, are deposits of the Jerome and Bradshaw MountainjQuadrangles, Arizona: U.S. Geological Survey Bulletin 782, 192p.

Livingston, D. E., 1969, Geochronology of older Precambrian rocks inGila County, Arizona: Tucson, University of Arizona, PhDdissertation, 224 p.

Logan, R. E., and Hirsch, D. D., 1982, Geometry of detachmentfaulting and dike emplacement in southwestern Castle DomeMountains, Yuma County, Arizona, in Frost, E. G., and Martin, D.L., eds., Mesozoic-Cenozoic tectonic evolution of the ColoradoRiver region, California, Arizona, and Nevada; Anderson-Hamilton

82

123.

124 •

124A.

125.

126 •

127 •

128.

129 •

130.

131.

132.

133.

134 •

135 .

volume: San Diego, Cordilleran Publishers, p. 598-607.London, D., and Burt, D. M., 1978, Lithium pegmatites of the White

Picacho district, Maricopa and Yavapai Counties, Arizona, inBurt, D. M., and Pewe, T. L., eds., Guidebook to the geology ofcentral Arizona: Geological Society of America CordilleranSection, 74th annual meeting, Arizona Bureau of Geology andMineral Technology Special Paper 2, p. 61-73.

Longwell, C. R., 1963, Reconnaissance geology between Lake Mead andDavis Dam, Arizona-Nevada: U.S. Geological Survey ProfessionalPaper 374-E, 51 p.

Lowell, J. D., 1974, Regional characteristics of porphyry copperdeposits of the southwest: Economic Geology, v. 69, p. 601-617.

Malhotra, S., Margolin, S., Machacek, R. F., Vejins, V" Kelly, W.S., and Laurila, M., 1984, Recovery of manganese from low-gradedomestic sources (a minerals and materials contract reportprepared by Arthur D. Little, Inc.): U.S. Bureau of Mines, 171p.

Marvin, R. F., Naeser, C. H., and Mehnert, H. H., 1978, Tabulation ofradiometric ages - including unpublished K-Ar and fission trackagas - for rocks in southeast Arizona and southwest New Mexico,in ~allender, J. F., and others, eds., Land of Cochise;southeastern Arizona: New Mexico Geological Society Guidebook,29th annual field conference, p. 243-252.

Meyers, I. A., Smith, E. I., and Wyman, R. V., 1984, Relationship ofmineralization to detachment faulting at the Cyclopic Mine,Mohave County, Arizona: Geological Society of America abstractswith programs, v. 16, p. 324;

Moore, R. T., 1972, Geology of the Virgin and Beaverdam Mountains,Arizona: Arizona Bureau of Mines Bulletin 186, 65 p.

Mot 00 va, J. M., San z a Ion e, R. F., and Cur tis, L. A., 197 9, 'A n a I y s e sof rocks and stream sediments of the Superstition Wilderness,Arizona: U.S. Geological Survey Open-File Report 78-483, 162 p.

Mouat, M. M., 1962, Manganese oxides from the Artillery Mountainsarea, Arizona: American Mineralogist, v. 47, p. 744-757.

Mueller, A., and Halbach, P., 1983, The Anderson Mine (Arizona) - anearly diagenetic uranium deposit in Miocene lake sediments:Economic Geology, v. 78, p. 275-292.

Nakata, J. K., 1982, Preliminary report on diking events in theMohave Mountains, Arizona, in Frost, E. G., and Martin, D. L.,eds., Mesozoic-Cenozoic tectonic evolution of the Colorado Riverregion, California, Arizona, and Nevada; Anderson-Hamiltonvolume: San Diego, California, Cordilleran Publishers, p. 85-90.

Naruk, S. J., 1983, Calculation of shear strain and translationvalues from mylonitic gneiss in a metamorphic core complex:Tucson, University of Arizona, M.S. thesis, 79 p.

Nichols, E. A., 1983, Geology of the Monte Cristo Vein area, BlackRock mining district, Yavapai County, Arizona: Tucson,University of Arizona, 63 p.

Otton, J. K., 1981, Geology and genesis of the Anderson Mine, acarbonaceous lacustrine uranium deposit, western Arizona; asummary report: U.S. Geological Survey Open-File Report 81-0780,25 p.

83

136. 1982, Tertiary extensional tectonics and associated volcanismin west-central Arizona, in Frost, E. G., and Martin, D. L.,eds., Mesozoic-Cenozoic t~tonic evolution of the Colorado Riverregion, California, Arizona, and Nevada; Anderson-Hamiltonvolume: San Diego, California, Cordilleran Publishers, p.143-157.

136A. Parker, F. Z., 1966, The geology and mineral deposits of the Silverdistrict, Trigo Mountains, Yuma County, Arizona: San Diego, SanDiego State University, MS thesis, 147 p.

136B. Peterson, D. W., 1960, Geology of the Haunted Canyon quadrangle,Arizona: U.S. Geological Survey Geologic Map GQ-128, scale1:24,000.137. Peterson, D. W., and Jinks, J. E., 1983, Mineralresource potential maps of the Superstition Wilderness andcontiguous roadless areas, Maricopa, Pinal, and Gila Counties,Arizona: U.S. Geological Survey Open-File Report 83-472, scale1:24,000.

138. 1984, Superstition Wilderness area in Marsh S. P. andothers, eds., Wilderness minera potential; assessment 0

mineral-resource potential in U.S. Forest Service lands studied1964-1984: U.S. Geological Survey Professional Paper 1300, v.1,p. 113-116.

139. Peterson, N. P., 1938, Geology and ore deposits of the Mammoth miningcamp area, Pinal County, Arizona: Arizona Bureau of MinesBulletin 144, 63 p.

140. Phillips, C. H., 1976, Geology and exotic copper mineralization inthe vicinity of Copper Butte, Pinal County, Arizona, in Woodward,L. A., and Northrop, S. A., eds., Tectonics and mineralre~Durces

of southwestern North America: New Mexico Geological SosieiySpecial Publication #6, p. 174-179.

141. Phillips, C. H., Cornwall, H. R., and Rubin, M., 1971, A Holocene orebody of copper oxides and carbonates at Ray, Arizona: EconomicGeology, v. 66, no. 3, p. 495-498.

142. Pietenpol, D. J., 1983, Structure and ore deposits of the Silverdistrict, La Paz County, Arizona: Tucson, University of Arizona,MS thesis, 67 p.

143. Ransome, F. L., 1923, Geology of the Oatman gold district, Arizona:U.S. Geological Survey Bulletin 743, 58 p.

144. Ratte, J. C., and Hedlund, D. C., 1981 (1982), Geologic map of theHells Hole Further Planning area (Rare II), Greenlee County,Arizona and Grant County, New Mexico: U.S. Geological SurveyMiscellaneous Field Studies Map MF-1344-A, scale 1:62,500.

145. Rehrig, W. A., 1982, Metamorphic core complexes of the southwesternUnited States - an updated analysis, in Frost, E. G., and Martin,D. L., eds., Mesozoic-Cenozoic tectonic evolution of the ColoradoRiver region, California, Arizona, and Nevada; Anderson-Hamiltonvolume: San Diego, Cordilleran Publishers, p. 551-581.

146. Rehrig, W. A., and Heidrick, T. L., 1972, Regional fracturing inLaramide stocks of Arizona and its relationship to porphyrycopper mineralization: Economic Geology, v. 67, no. 2, p.198-213.

147. 1976, Regional tectonic stress during the Laramide and LateTertiary intrusive periods, Basin and Range Province, Arizona:

84

Arizona Geological Society Digest, v. 10, p. 205-228.148. Rehrig, W. A., and Reynolds, S. J., 1980, Geologic and geochronologic

reconnaissance of a northwest trending zone of metamorphic corecomplexes in southern and western Arizona, in Crittenden, M. p.,Jr., Coney, P. J., and Davis, G. H., eds., Cordilleranmetamorphic core complexes: Geological Society of America Memoir153, p. 131-157.

149. Rehrig, W. A., Shafiqullah, M., and Damon, P. E., 1980,Geochronology, geology and listric normal faulting of the VultureMountains, Maricopa County, Arizona: Arizona Geological SocietyDigest v. 12, p. 89-110.

150. Reiter, B. E., 1981, Controls on lead-zinc skarn mineralization, IronCap Mine area, Aravaipa district, Graham County, Arizona: ArizonaGeological Society Digest, v. 13, p. 117-126.

151. Reynolds, S. J., 1980, Geologic framework of west-central Arizona:Arizona Geological Society Digest, v. 12, p. 1-16.

152. Reynolds, S. J., 1982, Geology and geochronology of the SouthMountains, Central Arizona: Tucs,on, University of Arizona,dissertation, 220 p.

153. Reynolds, S. J., and Spencer, J. E., 1984, Preliminary geologic mapof the Aguila Ridge-Bullard Peak area, west-central Arizona:Arizona Bureau of Geology and Mineral Technology Open-File Report84-4, scale 1:24,000.

154. Richter, D. H., Shafiqullah, M., and Lawrence, V. A., 1981, Geologicmap of the Whitlock Mountains, and vicinity, Graham County,Arizona: U.S. Geological Survey Miscellaneous Investigations Map1-1302, scale 1:48,000.

155. Richter, D. H., Houser, B. B., and Damon, P. E., 1983, Geologic mapof the Guthrie quadrangle, Graham and Greenlee Counties, Arizona:U.S. Geological Survey Miscellaneous Investigations Map 1-1455,scale 1:48,000.

156. Richter, D. H., and Lawrence, V. A., 1983, Mineral deposit map of theSilver City 1 x 2 quadrangle, New Mexico and Arizona: U.S.Geologic Survey Miscellaneous Investigation Map I-1310-B, scale1:250,000.

157. Romslo, T. M., 1948, Antler copper-zinc deposit, Mohave County,Arizona: U.S. Bureau of Mines Report of Investigations 4214, 14p.

158. 1950, Investigation of Lakeshore copper deposits, Pinal County,Arizona: U.S. Bureau of Mines Information Circular 4706, 24 p.

159. Ross, C. P., 1925, Geology and ore deposits of the Aravaipa andStanley mining districts, Graham County, Arizona: U.S.Geological Survey Bulletin 763, 120 p.

160. Rytuba, J. J., Till, A. B., Blair, W., and Haxel, G., 1978,Reconnaissance geologic map of the Quijotoa Mountains Quadrangle,Pima County, Arizona: U.S. Geological Survey Miscellaneous FieldStudies Map MF-937, scale 1:62,500.

161. Sabins, F. F., Jr., 1957, Geology of the Cochise Head and westernpart of the Vanar Quadrangle, Arizona: Geological Society ofAmerica Bulletin, v. 68, no. 10, p. 1315-1342.

162. Scarborough, R. B., 1981, Radioactive occurrences and uraniumproduction in Arizona; final report: Arizona Bureau of Geology

85

and Mineral Technology, Geological Survey Branch, Tucson,Arizona, GJBX-143(81), 297 p.

163. Scarborough, R. B., and Wilt, J., 1979, A study of uraniumfavorability of Cenozoic sedimentary rocks, Basin and RangeProvince, Arizona; Part I, General geology and chronology ofpre-late Miocene Cenozoic sedimentary rocks: U.S. GeologicalSurvey Open-File Report 79-1429, 106 p.

164. Schmidt, E. A., 1967, Geology of the Mineral Mountain Quadrangle,Pinal County, Arizona: Tucson, University of Arizona, MS thesis,III p.

165. Schrader, F. C., 1909, Mineral deposits of the Cerbat Range, BlackMountains and Grand Wash Cliffs, Mohave County, Arizona: U.S.Geological Survey Bulletin 397, 226 p.

166. Schwartz, G. M., 1953, Geology of the San Manuel copper deposit,Arizona: U.S. Geological Survey Professional Paper 256, 65 p.

167. Shackelford, T. J., 1976, Structural geology of the RawhideMountains, Mohave County, Arizona: Los Angeles, CA, Universityof Southern California, PhD dissertation, 176 p.

168. 1980, Tertiary tectonic denudation of a Mesozoic-earlyTertiary(?) gneiss complex, Rawhide Mountains, western Arizona:Geology, v. 8, p. 190-194.

169. Sherborne, J. E., Buckovic, W. A., DeWitt, D. B., Helliniger, T. S.,and Pavlak, S. J., 1979, Major uranium discovery involcanoclastic sediments, Basin and Range Province, YavapaiCounty, Arizona: American Association of Petroleum GeologistsBulletin, v. 63, p. 621-646.

170. Simons, F. S., 1961, Geologic map and sections of the KlondykeQuadrangle, Arizona: U.S. Geological Survey Open-File R~p~t~, 2p •

171. 1963, Composite dike of andesite and rhyolite at Klondyke,Arizona: Geological Society of America Bulletin, v. 74, no. 8,p. 1049-1056.

172. 1964, Geology of the Klondyke Quadrangle, Graham and PinalCounties, Arizona: U.S. Geological Survey Professional Paper461, 173 p.

173. Spatz, D. M., 1974, Geology and alteration-mineralization zoning ofthe Pine Flat porphyry copper occurrence, Yavapai County,Arizona: Tucson, University of Arizona, MS thesis, 148.

174. Spencer, J. E., Reynolds, S. J., and Welty, J. W., 1982-1985,unpublished data; available at the Arizona Bureau of Geology andMineral Technology, Tucson, AZ 85719.

175. Spencer, J. E., Welty, J. W., and Allen, G., Mid-Tertiary oredeposits in Arizona, in Jenney, J., and Reynolds, S. J., eds., Asummary of Arizona geology: Arizona Geological Society, inpress.

176. Stewart, L. A., and Pfister, A. J., 1960, Barite deposits of Arizona:U.S. Bureau of Mines Report of Investigations 5651, 89 p.

177. Suneson, N. H., 1980, The origin of bimodal volcanism, west-centralArizona: Santa Barbara, CA, University of California, PhDdissertation, 293 p.

178. Theodore, T. G., Keith, W. J., and Creasey, S. C., 1978, Calc-alkalicintrusive rocks at Mineral Mountain, south-central Arizona

86

(abs.): U.S. Geological Survey Professional Paper 1100, p. 74.179. Theodore, T. G., Keith, W. J., Till, A. B., Peterson, J. A., and

Creasey, S. C., 1978, Preliminary geologic map of the MineralMountain Quadrangle, Arizona: U.S. Geological Survey Open-FileReport 78-468, scale 1:24,000.

179A. Theodore, T. G., Blair, W. N., and Nash, J. T., 1982, Preliminaryreport on the geology and gold mineralization of the Gold BasinLost Basin mining districts, Mohave County, Arizona: U.S.Geological Survey Open-File Report 82-1052, 322 p.

180. Thomas, B. E., 1949, Ore deposits of the Wallapai district, Arizona:Economic Geology, v. 44, no. 8, p. 663-705.

181. 1951, The Emerald Isle copper deposit (discussion): EconomicGeology, v. 46, p. 231-233.

182. Thorman, C. H., and Drewes, H. 1981, Geology of the Rincon Wildernessstudy area, Pima County, Arizona: U.S. Geological SurveyBulletin 1500-A, p. 5-38.

183. Thorson J. P., 1971, Igneous petrology of the Oatman district,Mo ave County, Arizona: Santa Barbara, University of California,PhD dissertation, 189 p.

184. U.S. Bureau of Mines, Mineral Inventory Location System, U.S. Bureauof Mines computer data bank, (MILS): U.S. Bureau of Mines,Denver,Colorado, 80225. Data available for inspection at ArizonaBureau of Geology and Mineral Technology, Tucson, Arizona 85719.

185. U.S. Geological Survey, Mineral Resource Data System, U.S. GeologicalSurvey computer data bank (MRDS): U.S. Geological Survey, MenloPark, California, 94025. Data available for inspection atArizona Bureau nf Geology and Mineral Technology, Tucson, Arizona85719.

186. 1971, Aeromagnetic map of the Bradshaw Mountains and vicinity,Yavapai County, Arizona: U.S. Geological Survey GeophysicalInvestigations Map GP-758, scale 1:62,500.

187. Warren, H. V., and Loofbourow, R. W., 1932, The occurrence anddistribution of the prec.ious metals in the Montana and Idahomines, Ruby, Arizona: Economic Geology, v. 27, p. 578-585.

188. Weidner, M. I., 1957, Geology of the Beacon Hill-Colossal Cave area,Pima County, Arizona: Tucson, University of Arizona, MS thesis,34 p.

189. Wilkins, J., Jr., and Heidrick, T. L., 1982, Base and precious metalmineralization related to low-angle tectonic features in theWhipple Mountains, California, and Buckskin Mountains, Arizona,in Frost, E. G., and Martin, D. L., eds., Mesozoic-Cenozoictectonic evolution of the Colorado River region, California,Arizona, and Nevada; Anderson-Hamilton volume: San Diego,California, Cordilleran Publishers, p. 182-203.

190. Wilson, E. D., 1933a, Geology and mineral deposits of southern YumaCounty, Arizona: Arizona Bureau of Mines Bulletin 134, 236 p.

191. 1933b, Arizona gold placers and gold placering, 4th edition,revised: Arizona Bureau of Mines Bulletin 135, 148 p.

192. 1941, Tungsten deposits of Arizona: Arizona Bureau of MinesBulletin 148, 54 p.

193. 1952, Arizona gold placers and placering, 5th edition revised:Arizona Bureau of Mines Bulletin 160, p. 11-86.

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194. Wilson, E. D., Cunningham, J. B., and Butler, G. M., 1934, Arizonalode-gold mines and gold mining: Arizona Bureau of MinesBulletin 137, 261 p.

195. Wilson, E. D., and Moore, R. T., 1959a, Geologic map of MohaveCounty, Arizona: Arizona Bureau of Mines, scale 1:375,000.

196. 1959b, Geologic map of Pinal County, Arizona: Arizona Bureauof Mines, scale 1:375,000.

197. Wilson, E. D., Moore, R. T., and a'Haire, R. T., 1960, Geologic mapof Pima and Santa Cruz Counties, Arizona: Tucson, Arizona Bureauof Mines, scale 1:375,000.

198. Wilson, E. D., Moore, R. T., and Peirce, H. W., 1957, Geologic map ofMaricopa County, Arizona: Arizona Bureau of Mines, scale1:375,000.

199. 1959, Geologic map of Gila County, Arizona: Arizona Bureau ofMines, scale 1:375,000.

200. Wilson, W. E., and Miller, D. K., 1974, Minerals of the Rowley mine:Mineralogical Record, v. 5, no. 1, p. 10-30.

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