DATA-BASE MAP
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DD D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D DD D D D D D D D D D D D D D & & & & & & & & & & & & & & & & & & & && & & & & & & && & & & & & & & & & & & & & & && & & & & EC-21 # # # # # # # # # # # # # # # # # # # # # ## # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # DALBO MAPLE RIDGE ST ANCHFIELD CAMBRIDGE SP R INGV ALE WY ANETT SPENCER BROOK BRADFORD ISANTI NORTH BRANCH OXFORD A THENS ST ANFORD North Stanchfield Lake Grass Lake Matson Lake Lake Krone Mud Lake Upper Rice Lake Seventeen Lake Linderman Lake Trollin Lake Krans Lake Long Lake Little Stanchfield Lake Adams Lake Rum Lake Twin Lake Dollar Lake Skogman Lake Mud Lake Elms Lake Florence L ake Williams Lake Brobergs Lake Green Barton Tennyson Lake Baxter Lesure Heath Lake Radke Lake Sandy Lake Bear Lake Mud Lake Stony Lake Marget Lake Beckman Lake Hoffman Lake Long Lake Tamarack Lake L o wer Birch Lake Upper Birch Lake Hurley Lake Twin Lakes Horseley Lake Mud Lake Horseshoe Lake Knute Lake Rice Lake Grass Lake Spring Lake Big Pine Lake Little Pine Lake Bloomgren Lake Elizabeth Lake Lake Lake Lake Lake Lake Lake Lake Lake Lake Lake Lake Lake Lake Lake Spectacle Long German Stratton Lake Typo Lake Fannie Francis Stanchfield Stanchfield Section Long Stanchfield South Stanchfield Lory Blue Lake Lindgren 6 1 31 36 6 1 31 36 6 1 36 31 6 1 36 31 6 1 36 31 6 1 36 31 6 1 36 31 6 1 36 1 31 6 1 6 1 6 31 36 6 1 6 1 36 1 6 31 19 24 19 24 19 24 19 24 W y a n e tt North Brook River Rum Brook Brook River Rum River Rum River Rum North Branch Branch West Sunrise Sunrise River River Creek Cedar Brook Brook Brook Creek Creek Creek Creek Creek Branch Lower Beckins Green Pine Ties Ties Spencer Seeleye Isanti Creek ) 47 ) 47 ) 95 ) 95 ) 65 ) 107 ) 65 ) 95 ) 65 ) 95 ) 47 ) 65 Braham Cambridge Isanti T . 37 N. T . 36 N. T . 35 N. T . 34 N. R. 24 W. R. 25 W. R. 23 W. R. 24 W. R. 23 W. T . 34 N. T . 35 N. R. 22 W. T . 36 N. T . 37 N. R. 22 W. MILLE LACS COUNTY KAN ABEC COUNTY P I N E KANABEC COUNTY C H IS A G O C O U N T Y C H I S A G O C O U N T Y A N O K A C OU N T Y S H E R B U R N E C O U N T Y MILLE LACS COUNTY COUNTY 9 3 ° 3 0' 93° 22' 30'' R. 25 W. 45° 37' 30'' 93° 15' 45° 37' 30'' 93° 7' 30'' 45° 30' 93° 7' 30'' 93° 15' 45° 30' 93° 22' 30'' A N OK A CO UN TY 9 3 ° 3 0' 290 290 280 300 310 320 270 300 300 290 290 300 290 290 290 300 290 290 290 290 290 300 290 290 290 280 280 300 290 300 300 280 300 300 290 290 290 290 290 300 290 290 290 280 290 280 300 280 300 290 290 290 300 290 280 280 300 280 280 290 290 290 280 290 290 310 290 300 290 290 290 310 290 290 290 300 300 290 290 290 290 290 300 290 280 290 290 290 310 280 300 300 280 270 310 290 300 290 310 290 290 290 290 290 300 300 280 290 290 280 290 280 280 280 310 290 290 300 290 290 290 290 280 290 300 300 300 290 290 280 290 290 280 310 290 280 290 300 310 300 280 290 280 280 280 290 300 290 290 280 300 290 280 290 290 280 280 290 290 300 290 290 290 290 290 300 300 290 300 290 290 300 280 310 320 300 290 290 290 290 300 290 290 300 280 290 280 300 280 290 290 AR-2 IS-4 IS-5 IS-1 IS-3 IS-2 AR-1 X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X XX X X X X X X X X X X X X X X & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - & - E E E E E E k k k k k k k k k k k k k k k k k k k k k k k k k k k k k k k k k k k k k THE DATA-BASE MAP The types, locations, and density of information used to prepare the Isanti County atlas are shown on this map. The data are described below to aid the user in assessing what types may be useful for a particular information need. The Data-Base Map serves as a guide to the precision of the other maps in the atlas. It shows where data are sparse or lacking and interpretation and extrapolation were required to prepare the maps. All data were collected by Minnesota Geological Survey staff unless otherwise specified. DRILL-HOLE INFORMATION A record of water-well construction (well driller's log) is a water-well contractor's description of the geologic materials penetrated during drilling and the construction materials used to complete the well. Not all wells extend to bedrock. In areas of thick, unconsolidated Quaternary deposits, drillers commonly do not need to drill through the entire thickness of overburden to find sufficient groundwater. Hydrologic data, such as the static water level and test-pumping results, are commonly included. Before any driller's log can be used, the location of the well must be verified, and a geologist must interpret the log. Driller's logs are the primary source of subsurface geologic and hydrologic data for Isanti County; about 5,700 logs were used for this atlas; they can be found in the County Well Index (CWI). Core samples were collected at various sites throughout Isanti County as a means to establish the nature of the subsurface material. Site EC-21 (in the northwest corner of the county) is a bedrock core sample, which was retrieved by diamond core drilling. This method uses a diamond bit rotating at the end of a drill rod. A column of rock moves up the drill pipe and is recovered at the surface for study. Rotary-sonic cores were collected by the Minnesota Geological Survey at seven sites in the county (labelled AR-1, AR-2, IS-1, IS-2, IS-3, IS-4, and IS-5) to aid both the interpretation of the Quaternary deposits and in determining bedrock depth and nature. The coring technique enables recovery of a continuous core, 3.5 inches (8.9 centimeters) in diameter, from glacial deposits and bedrock (where intersected). It provides excellent subsurface samples for detailed study and comparison with cuttings, geophysical logs, and driller's logs from surrounding sites. Detailed geologist's logs for the seven cores are shown on Plate 4, Quaternary Stratigraphy. These logs are entered into the County Well Index (CWI) and any sampling results are available in Minnesota Geological Survey file data. The core is available for inspection at the Minnesota Department of Natural Resources Drill Core Library in Hibbing. Cutting samples collected during drilling provide physical evidence of subsurface geologic materials. Cuttings are the samples generated as the drill bit cuts through the subsurface material and are used to interpret and verify driller's logs. They are logged and stored at the Minnesota Geological Survey. Borehole geophysical logs are created by lowering instruments down a well or drill hole and measuring the physical and chemical properties of the geologic materials through which the hole passes. Different logging techniques measure naturally occurring gamma radiation, spontaneous potential, and resistivity. Gamma logs characterize in graphic form the geologic formations penetrated. Spontaneous potential and resistivity are mainly used to locate water levels in wells and the depth of the well casing. An interpretive log is prepared from the geophysical log and correlated with drilling samples from the same hole, information obtained from nearby exposures, or a geophysical log from a nearby drill hole. Geophysical logs can provide high- quality subsurface geologic and hydrologic information for wells that have little or no other information available. The information obtained from a geophysical log is added to the County Well Index (CWI) and the paper log is on file at the Minnesota Geological Survey. Soil borings are test holes drilled to obtain information about the physical properties of subsurface materials for engineering, mapping, or exploration purposes. They are logged by an engineer or a geologist using a variety of classification schemes based on particle sizes, penetration rate, moisture content, and color. Soil-boring data were collected by the Minnesota Department of Transportation and the Isanti County Highway Department. Their distribution is scattered along various highways and county roads in Isanti County. These data are most useful in determining the composition of unconsolidated deposits. Descriptions of the geologic materials penetrated can be accessed in digital and paper files at the Minnesota Geological Survey. Minnesota Department of Transportation data are available from the Foundations Unit web page (http://www.dot.state.mn.us/materials/foundations.html). Giddings probe holes are borings of glacial materials, 2 inches (5.1 centimeters) in diameter, collected by a truck-mounted hydraulic auger. A description was generated at every site and samples were taken for textural analyses at most locations. Samples were generally taken about every 5 feet (1.5 meters), at unit contacts, or where the geologist believed it was important. OTHER INFORMATION Field sites are natural and artificial exposures of unconsolidated Quaternary deposits that were described in detail; samples from many sites were texturally analyzed. Field sites include stream and river cuts, gravel pits, excavations, and road cuts. Data from field sites can be found in Minnesota Geological Survey files. Additional gravel pit data may be found on the Minnesota Department of Transportation Aggregate Source Information System web page (http://www.dot.state.mn.us/materials/aggsource.html). Textural analyses express the proportion of sand, silt, and clay-size particles that make up a sample. The samples analyzed were taken from natural and artificial exposures, Giddings holes, soil auger holes, and the rotary-sonic cores. They are helpful in determining the origin, correlation, and hydrologic properties of unconsolidated sediments. The data are available in Minnesota Geological Survey files. Gravity and aeromagnetic (airborne-magnetic) data that are available at the Minnesota Geological Survey are used to assist mapping Precambrian geology. The utility of these two data sets relies on the strong contrasts in density and magnetization that commonly exists between various Precambrian rocks. The aeromagnetic data in Isanti County were acquired 500 to 650 feet (152 to 198 meters) above ground along flight lines spaced 0.25 to 0.33 mile (402 to 531 meters) apart, and are compiled into a 328-foot (100-meter) grid (line and grid data are not indicated on the map due to high density). The gravity data are based on ground- based stations that are spaced about a mile (1.6 kilometers) apart along roads. Precambrian rocks are present at the bedrock surface only in the northwestern part of Isanti County, but the gravity and aeromagnetic data can be helpful in mapping some Paleozoic structures that may be related to reactivation of Precambrian faults. Passive seismic depth to bedrock soundings provide information based on measurement and analysis of ambient shear- and surface-wave energy in the ground that allows a calculation of the depth to bedrock (thickness of Quaternary deposits) beneath that point. The measurements employ a recording seismograph system that is implanted into the ground surface and records ambient ground vibrations in three orthogonal directions (2 horizontal and 1 vertical) during a 16-minute interval. The method is called passive because no energy is directly input into the ground at the time of measurement, such as is the case for conventional seismic sounding. Instead, the unit measures background vibrations from a variety of natural and artificial sources that include machinery, traffic, and wind. The averaged horizontal spectra of the seismic noise is divided by the corresponding vertical spectrum, and the resulting Horizontal to Vertical Spectral Ratio (HVSR) should display a prominent peak that closely approximates the resonant frequency (shear wave) of the unconsolidated sequence overlying the bedrock surface. The resonant frequency of unconsolidated overburden is a useful parameter for seismic risk investigations, but here it is used to estimate the thickness of the overburden itself, which in our case is the Quaternary sequence. In this application, the HVSR method is calibrated by taking measurements at locations where the thicknesses of Quaternary deposits are known from either well data or from conventional seismic sounding. The control points are selected to approximately span the expected range of bedrock depths for the region, and the calibration curve that is fitted to these data can be used to estimate bedrock depth in areas lacking either drill hole or seismic control. In general, depth to bedrock calculated by this method can have errors up to 25 percent of the depth; however, in areas with little to no other data, this is still useful information and many soundings can be inexpensively collected over a short period of time by one or two operators. Seismic refraction soundings measure the time required for sound or pressure waves to travel from a source through the subsurface and be refracted back to a receiver. Travel time can be correlated with the density and rigidity of the geologic material. Precambrian and Paleozoic rocks usually exhibit pressure-wave velocities that are 1.5 to 2.5 times those of unconsolidated Quaternary sediments below the water tables. The spacing of the receivers (geophones) and the arrival times (measured in milliseconds) are used to calculate the depth to bedrock. Seismic refraction soundings are more labor intensive than passive seismic soundings, but can provide velocity information and higher-quality depth estimates. No seismic refraction soundings were acquired for the Isanti County Geologic Atlas, but the results of five soundings that were previously acquired by H.M. Mooney of the University of Minnesota were included. DATA-BASE MAP By Margeurite C. Pettus and V.W. Chandler 2017 MINNESOTA GEOLOGICAL SURVEY Harvey Thorleifson, Director Prepared and Published with the Support of THE ISANTI COUNTY BOARD OF COMMISSIONERS, THE MINNESOTA ENVIRONMENT AND NATURAL RESOURCES TRUST FUND AS RECOMMENDED BY THE LEGISLATIVE-CITIZEN COMMISSION ON MINNESOTA RESOURCES, AND THE MINNESOTA LEGACY AMENDMENT'S CLEAN WATER FUND Every reasonable effort has been made to ensure the accuracy of the factual data on which this map interpretation is based; however, the Minnesota Geological Survey does not warrant or guarantee that there are no errors. Users may wish to verify critical information; sources include both the references listed here and information on file at the offices of the Minnesota Geological Survey in St. Paul. In addition, effort has been made to ensure that the interpretation conforms to sound geologic and cartographic principles. No claim is made that the interpretation shown is rigorously correct, however, and it should not be used to guide engineering-scale decisions without site-specific verification. COUNTY ATLAS SERIES ATLAS C-44, PART A Isanti County Plate 1—Data-Base Map CONTOUR INTERVAL 10 METERS 1 0 1 2 3 4 5 MILES 8 KILOMETERS SCALE 1:100 000 1 0 1 2 3 4 5 6 7 LOCATION DIAGRAM GEOLOGIC ATLAS OF ISANTI COUNTY, MINNESOTA Digital base modified from the Minnesota Department of Transportation BaseMap data; digital base annotation by the Minnesota Geological Survey. Elevation contours were derived from the U.S. Geological Survey 30-meter Digital Elevation Model (DEM) by the Minnesota Geological Survey. Universal Transverse Mercator Projection, grid zone 15 1983 North American Datum ©2017 by the Regents of the University of Minnesota The University of Minnesota is an equal opportunity educator and employer GIS compilation by M.C. Pettus Edited by Lori Robinson INTRODUCTION The public health and economic development of Isanti County are directly dependent on the wise use and management of its land and water resources. Geologic and hydrologic information are essential before decisions are made that affect natural resources. Although the amount of geologic information required for making specific decisions can vary, the information will not be used if it is unavailable when needed, or if it is available only in a highly technical form, or scattered in many different maps and reports. The data bases described here address this need. County atlases, prepared jointly by the Minnesota Geological Survey and the Minnesota Department of Natural Resources, present detailed geologic and hydrologic information in an interpretive as well as descriptive form. Maps and texts summarize basic geologic and hydrologic conditions at a county scale, and interpret these conditions in terms of the impacts of possible land- and water-use decisions. Site-specific information is available in some areas at a greater level of technical detail than shown on the maps of this atlas. The data are too voluminous to present at the scale of this atlas, but have been incorporated into readily accessible files housed at the Minnesota Geological Survey. Several sources commonly provide information about an area or an individual property, but they may use different classification schemes to describe the same geologic materials. As a result, discrepancies in interpreting the data may arise or the different sources may appear to contradict each other. For example, water-well drillers may describe glacial till as "clay," but engineering records will describe it as "clayey sand." Both descriptions are acceptable for their original purpose of describing the physical attributes of the material. "Clay," the term used by well drillers, defines the general inability of the till to yield groundwater to a well. "Clayey sand," the term from the engineering record, defines the physical composition of the till relative to particle size and engineering properties. The geologist must take the analysis one step further and define the material in terms of how it formed rather than how it is to be used. In this example, till consists of an unsorted mixture of rock fragments ranging in size from clay to cobbles and boulders, and it is interpreted by the geologist as having been deposited directly by glacial ice. Understanding the process by which the material formed allows geologists to make predictions about what lies between and beyond data points. All of the types of data described on this plate were interpreted by geologists or hydrogeologists to make them meaningful for mapping purposes. The 1:100,000 scale of the maps in this atlas was chosen because it shows the geologic and topical studies of the county while keeping the physical size of each plate to a manageable level. As a result, some detailed information that was gained by data interpretation and mapping cannot be shown on these maps or discussed in the texts. Some of this information is available in digital files that accompany the atlas. Whether to use the atlas alone, or in combination with the data bases, depends on the amount of detail needed. Generally, data-base information must be used to evaluate site- specific conditions. DATA-BASE MANAGEMENT All of the data shown on the map were plotted on 7.5-minute topographic quadrangle maps or highway alignment maps and assigned inventory numbers. Automated data bases and a few manual files were developed to provide easy access and rapid retrieval of these site-specific data. The data may be obtained from the Minnesota Geological Survey. Computer storage and retrieval systems are better than manual files for manipulating large amounts of data because automated geologic data bases can be designed to interact with other computer files, such as land-use data. Such interaction permits more efficient assessment of cause-and-effect relationships concerning natural resources than is commonly possible with manual files. ISANTI COUNTY DATA BASES Computerized files were developed for point-source data such as wells and borings in Isanti County. They use Public Land Survey descriptions, Universal Transverse Mercator (UTM), and latitude-longitude coordinates as location criteria; thus, they are compatible with the natural- resource data bases housed at the Minnesota Land Management Information Center (LMIC). The computerized data base developed for Isanti County by the Minnesota Geological Survey is the County Well Index (CWI). County Well Index (CWI)—Information from water-well records and exploration holes is entered into this statewide data base. Each well log is assigned a six-digit unique number and each exploration drill hole is assigned either a five- or six-digit unique number. These reference numbers are also used by state agencies and the Water Resources Division of the U.S. Geological Survey. Elevations, expressed in feet above sea level, were determined either from topographic maps (see the index to 7.5-minute quadrangles) or Minnesota's lidar high- resolution elevation data set. Elevations from the topographic maps are generally accurate to plus or minus 5 feet (1.5 meters), and the lidar elevations are generally accurate to within 3 feet (1 meter). The street address of each well is also included wherever possible to provide data users with a well-location system that is compatible with local regulatory programs. Software at the Minnesota Geological Survey is used to display and tabulate many of the data elements contained on the original well log. The County Well Index is currently stored in a data base that consists of ten related tables. These tables contain information such as well depths, well construction, addresses, aquifers, dates drilled, static water levels, and pumping test data. They also contain alternate well identifiers such as permit numbers or emergency-service numbers, the well stratigraphy (the geologic materials encountered during drilling), and the azimuth and inclination of angled exploration holes. CWI application software developed by the Minnesota Department of Health provides two types of reports: WELL LOG contains all the information about the well as it was reported by the contractor (Fig. 1). There may also be additional location information, land-surface elevation, aquifer designation, and remarks about the drill hole. WELL STRATIGRAPHY contains the geologic log with a geologist's stratigraphic interpretations, which are based on her or his knowledge and understanding of the geology of Isanti County and augmented in some cases by additional data sources, such as cuttings, borehole geophysical logs, or core (Fig. 2). Only those drill holes with verified locations have stratigraphy assigned to them. File data of the Minnesota Geological Survey—Details about other types of data shown on this plate are available from digital (including the Quaternary Data Index, an internal working data base) and paper files at the Minnesota Geological Survey. These include descriptions of cutting samples, soil borings, Giddings probe holes, field sites, soil auger holes, textural analyses, gravity and aeromagnetic data, passive seismic sites, and aggregate resources sites. FUTURE DATA COLLECTION Additional geologic information is generated continuously as new water wells are drilled, construction activities expose more bedrock, or additional wells are tested for water quality. To address this, the library of information prepared for Isanti County is flexible so that old data can be reevaluated in light of new information, and new forms of data can be added if required. The need to manage groundwater and other natural resources wisely will never become outdated. Future demands on these resources will require current data to assess the impacts. ACKNOWLEDGEMENTS The staff from the Isanti Soil and Water Conservation District and the staff from the City of Cambridge contributed greatly to the development of the County Well Index (CWI) data base. We thank local water-well contractors and landowners for their assistance. D AL BO P R IN C E T O N NE S PRING V A LE BR A H A M P R I NC E T O N W Y ANE TT BR A DF ORD C AMBRID G E S TA R K LAK E F R E M O NT CR OWN S T . F R A NCIS IS A N TI TY P O LA K E INDEX TO 7.5-MINUTE QUADRANGLES County Well Name Range Dir Township Section Subsection Well Depth Depth Completed Date Well Completed Update Date Isanti DNR OB 30016 25 W 35 DDDCDD 36 No 262.00 262.00 2010/09/10 ft ft Make Static Water Level Open Hole(ft.) From Last Strat g.p.m. hrs. pumpting Grouting Information Capacity Well disinfected upon completion? Pump Variance Abandoned Wells Screen Nearest Known Source of Contamination Well Contractor Cerfication BRIAN & TONY ü ü ü ü 230.0 262.0 Quad Depth to Bedrock Pumping Level (below land surface) Model 153C 961.00 1404 Mt.Simon-Hinckley Pitless adapter manufacturer ft. Well grouted? feet Direction Type Printed on Model number Manufacture's name REPORT Type Wellhead Completion ü 300 S BYD 210.00 MN DNR 500 LAFAYETTE RD 55155 ST PAUL MN Changed contact address DNR SPECTACLE SITE 39 CR MN well address MINNESOTA DEPARTMENT OF HEALTH MINNESOTA STATUTES CHAPTER 1031 WELL AND BORING RECORD Description From To (ft.) Color Hardness FINE SAND V.SOFT TAN 18 0 COARSE SAND & GRAVEL SOFT 30 18 CLAY TILL MEDIUM GRAY 45 30 FINE SANDS SOFT BRN/TAN 70 45 COARSE SAND & GRAVEL SFT-MED 140 70 COARSE SAND & GRAVEL SOFT 194 140 CLAY SOFT BROWN 199 194 COARSE SAND & GRAVEL TAN 209 199 MT. SIMON SANDSTONE SFT-MED YELLOW 210 209 MT. SIMON SANDSTONE SFT-MED YELLOW 251 210 HINCKLEY SANDSTONE HARD RED 252 251 HINCKLEY SANDSTONE HARD RED 262 252 Remarks GAMMA LOGGED 9-2-2010. M.G.S. NO. 5022. LOGGED FOR DNR. LOGGED IN 10 IN. DIAMETER BOREHOLE. SPECTACLE LAKE WMA (SP). USE = ENV BORE HOLE PER MEMO DATED 9/26/2011. WELLHEAD COMPLETION: CASING PROTECTION= PROTOP & BUMPER POSTS. DRILLERS: BRIAN TRAUT & TONY NOVAK. DNR GEOLOGIST ON SITE FOR SAMPLING. HE-01205-07 (Rev. 2/99) Date Lic. or Reg No. Mark J Traut Wells, Inc. Was a variance granted from the MDH for this well? Does property have any not in use and not sealed well(s)? 11/15/2016 d e l l a t s n I e t a D d e l l a t s n I t o N Type Length of drop pipe HP Volts g.p.m To 262.0 10.00 4.00 in. from to 230.00 0.00 ft. 10.79 lbs/ft to neat cement 0.0 230.0 7.25 o T m o r F l a i r e t a M ft. Cubic yards Hole Diameter (in.) Elevation At-grate (Environmental Wells and Borings ONLY) Casing Protection 12 in. above grade Basement offset ü YES NO YES NO ü YES NO YES NO ft. after Date measured Material Diamter Length Set Slot 2010/09/10 34.50 land surface 2010/09/02 2014/08/07 2010/11/01 Entry Date Received Date Unique Well Number County Well Index v.5 Aquifer ft. First Bedrock CMTS PMHN Field Located ft. Quad Id MGS 779947 Wyanett License Business Name Name of Driller Diameter 4 Depth 230 Casing Type Steel (black or low Drive Shoe? YES NO Use environ. bore hole Water Drilling Fluid Well Hydrofractured? YES ü NO From ft. to Drilling Method Dual Rotary Drillhole Angle NOT SPECIFIED Figure 1. Example of a WELL LOG record, showing all the information about the well as reported by the well driller. Digitization (Screen) - Map (1:24 000) Unique Well Number County Isanti r i D e g n a R e m a N l l e W Township Section Subsection Depth Drilled Depth Completed Lic/Reg. No. Date Completed Quad Quad Id DNR OB 30016 25 W 35 DDDCDD 36 262 262 ft ft 1404 2010/09/10 Elevation 961.00 ft. Open Hole 230-262 Method 7.5 minute topographic Aquifer Mt.Simon-Hinckley Depth to Bedrock 210 ft. Field Located Program Uni No.Verified Location Method Input Source Input Date Universal Transverse Mercator(UTM) - NAD83 - Zone 15 - Meters UTM Northing (Y) UTM Easting (X) 467925 5045049 2010/09/02 Wyanett 2010/09/02 2014/08/07 2010/11/01 Entry Date Update Date Received Date MINNESOTA DEPARTMENT OF HEALTH WELL AND BORING RECORD MINNESOTA STATUTES CHAPTER 1031 Driller Name BRIAN & TONY SWL 34.5 779947 Information from owner Minnesota Geological Survey Minnesota Geological Survey Geological Material Minor Secondary DEPTH Primary ELEVATION LITHOLOGY Hardness Stratigraphy From To Thick From To Color John Mossler MGS Geologic study 1:24k to 1:100k y c n e g A n o i t a t e r p r e t n I c i g o l o e G Interpretation Method 153C FINE SAND TAN V.SOFT 18 sand-brown sand 18 961 943 0 COARSE SAND & GRAVEL gravel SOFT 30 sand +larger sand 12 943 931 18 CLAY TILL clay GRAY MEDIUM 45 till-gray till 15 931 916 30 FINE SANDS BRN/TAN SOFT 70 sand-brown sand 25 916 891 45 COARSE SAND & GRAVEL gravel SFT-MED 140 sand +larger sand 70 891 821 70 COARSE SAND & GRAVEL gravel SOFT 194 sand +larger sand 54 821 767 140 CLAY BROWN SOFT 199 clay-brown clay 5 767 762 194 COARSE SAND & GRAVEL gravel TAN 209 sand +larger-brown sand 10 762 752 199 MT. SIMON SANDSTONE gravel YELLOW SFT-MED 210 sand +larger sand 1 752 751 209 MT. SIMON SANDSTONE YELLOW SFT-MED 251 Mt.Simon Sandstone sandstone 41 751 710 210 HINCKLEY SANDSTONE RED HARD 252 Mt.Simon Sandstone sandstone 1 710 709 251 HINCKLEY SANDSTONE RED HARD 262 Hinckley Sandstone sandstone 10 709 699 252 Figure 2. Example of a WELL STRATIGRAPHY record, which contains a geologist's interpretation of the geologic materials listed by the driller in the WELL LOG record (Fig. 1). Additional downhole information for this well (as noted in the Interpretation Method on the record above) controls the geologist's interpretation, which may not match the driller's description of the geologic material penetrated. Note: More than one symbol can occur at the same location Record of water-well construction (well driller's log) Diamond drill core sample Rotary-sonic core sample Cutting sample Borehole geophysical log Soil boring Giddings probe hole Field site Textural analysis Gravity data Passive seismic sounding Seismic refraction sounding MAP SYMBOLS & k # & X E D ENVIRONMENT AND NATURAL RESOURCES TRUST FUND
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SPENCER BROOK BRADFORD ISANTI NORTH BRANCH
OXFORDATHENSSTANFORD
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MudLake
Upper Rice
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SeventeenLake
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LongLake
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RumLake
TwinLake
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SkogmanLake
MudLake
ElmsLake
FlorenceLake
WilliamsLake
BrobergsLake
Green
Barton
TennysonLake
Baxter
Lesure HeathLake
RadkeLake
SandyLake
BearLake
MudLake
StonyLake
MargetLake
BeckmanLake
HoffmanLake
LongLake
TamarackLake
LowerBirch
Lake
UpperBirchLake
HurleyLakeTwin
Lakes
HorseleyLake Mud
Lake
HorseshoeLake
KnuteLake
RiceLake
GrassLake
SpringLake
Big PineLake
Little PineLake
BloomgrenLake
ElizabethLake
LakeLake
Lake
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93° 30'
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THE DATA-BASE MAP
The types, locations, and density of information used to prepare the Isanti County atlas are shown on this map. The data are described below to aid the user in assessing what types may be useful for a particular information need. The Data-Base Map serves as a guide to the precision of the other maps in the atlas. It shows where data are sparse or lacking and interpretation and extrapolation were required to prepare the maps. All data were collected by Minnesota Geological Survey staff unless otherwise specified.
DRILL-HOLE INFORMATIONA record of water-well construction (well driller's log) is a water-well contractor's
description of the geologic materials penetrated during drilling and the construction materials used to complete the well. Not all wells extend to bedrock. In areas of thick, unconsolidated Quaternary deposits, drillers commonly do not need to drill through the entire thickness of overburden to find sufficient groundwater. Hydrologic data, such as the static water level and test-pumping results, are commonly included. Before any driller's log can be used, the location of the well must be verified, and a geologist must interpret the log. Driller's logs are the primary source of subsurface geologic and hydrologic data for Isanti County; about 5,700 logs were used for this atlas; they can be found in the County Well Index (CWI).
Core samples were collected at various sites throughout Isanti County as a means to establish the nature of the subsurface material. Site EC-21 (in the northwest corner of the county) is a bedrock core sample, which was retrieved by diamond core drilling. This method uses a diamond bit rotating at the end of a drill rod. A column of rock moves up the drill pipe and is recovered at the surface for study. Rotary-sonic cores were collected by the Minnesota Geological Survey at seven sites in the county (labelled AR-1, AR-2, IS-1, IS-2, IS-3, IS-4, and IS-5) to aid both the interpretation of the Quaternary deposits and in determining bedrock depth and nature. The coring technique enables recovery of a continuous core, 3.5 inches (8.9 centimeters) in diameter, from glacial deposits and bedrock (where intersected). It provides excellent subsurface samples for detailed study and comparison with cuttings, geophysical logs, and driller's logs from surrounding sites. Detailed geologist's logs for the seven cores are shown on Plate 4, Quaternary Stratigraphy. These logs are entered into the County Well Index (CWI) and any sampling results are available in Minnesota Geological Survey file data. The core is available for inspection at the Minnesota Department of Natural Resources Drill Core Library in Hibbing.
Cutting samples collected during drilling provide physical evidence of subsurface geologic materials. Cuttings are the samples generated as the drill bit cuts through the subsurface material and are used to interpret and verify driller's logs. They are logged and stored at the Minnesota Geological Survey.
Borehole geophysical logs are created by lowering instruments down a well or drill hole and measuring the physical and chemical properties of the geologic materials through which the hole passes. Different logging techniques measure naturally occurring gamma radiation, spontaneous potential, and resistivity. Gamma logs characterize in graphic form the geologic formations penetrated. Spontaneous potential and resistivity are mainly used to locate water levels in wells and the depth of the well casing. An interpretive log is prepared from the geophysical log and correlated with drilling samples from the same hole, information obtained from nearby exposures, or a geophysical log from a nearby drill hole. Geophysical logs can provide high-quality subsurface geologic and hydrologic information for wells that have little or no other information available. The information obtained from a geophysical log is added to the County Well Index (CWI) and the paper log is on file at the Minnesota Geological Survey.
Soil borings are test holes drilled to obtain information about the physical properties of subsurface materials for engineering, mapping, or exploration purposes. They are logged by an engineer or a geologist using a variety of classification schemes based on particle sizes, penetration rate, moisture content, and color. Soil-boring data were collected by the Minnesota Department of Transportation and the Isanti County Highway Department. Their distribution is scattered along various highways and county roads in Isanti County. These data are most useful in determining the composition of unconsolidated deposits. Descriptions of the geologic materials penetrated can be accessed in digital and paper files at the Minnesota Geological Survey. Minnesota Department of Transportation data are available from the Foundations Unit web page (http://www.dot.state.mn.us/materials/foundations.html).
Giddings probe holes are borings of glacial materials, 2 inches (5.1 centimeters) in diameter, collected by a truck-mounted hydraulic auger. A description was generated at every site and samples were taken for textural analyses at most locations. Samples were generally taken about every 5 feet (1.5 meters), at unit contacts, or where the geologist believed it was important.
OTHER INFORMATIONField sites are natural and artificial exposures of unconsolidated Quaternary deposits
that were described in detail; samples from many sites were texturally analyzed. Field sites include stream and river cuts, gravel pits, excavations, and road cuts. Data from field sites can be found in Minnesota Geological Survey files. Additional gravel pit data may be found on the Minnesota Department of Transportation Aggregate Source Information System web page (http://www.dot.state.mn.us/materials/aggsource.html).
Textural analyses express the proportion of sand, silt, and clay-size particles that make up a sample. The samples analyzed were taken from natural and artificial exposures, Giddings holes, soil auger holes, and the rotary-sonic cores. They are helpful in determining the origin, correlation, and hydrologic properties of unconsolidated sediments. The data are available in Minnesota Geological Survey files.
Gravity and aeromagnetic (airborne-magnetic) data that are available at the Minnesota Geological Survey are used to assist mapping Precambrian geology. The utility of these two data sets relies on the strong contrasts in density and magnetization that commonly exists between various Precambrian rocks. The aeromagnetic data in Isanti County were acquired 500 to 650 feet (152 to 198 meters) above ground along flight lines spaced 0.25 to 0.33 mile (402 to 531 meters) apart, and are compiled into a 328-foot (100-meter) grid (line and grid data are not indicated on the map due to high density). The gravity data are based on ground-based stations that are spaced about a mile (1.6 kilometers) apart along roads. Precambrian rocks are present at the bedrock surface only in the northwestern part of Isanti County, but the gravity and aeromagnetic data can be helpful in mapping some Paleozoic structures that may be related to reactivation of Precambrian faults.
Passive seismic depth to bedrock soundings provide information based on measurement and analysis of ambient shear- and surface-wave energy in the ground that allows a calculation of the depth to bedrock (thickness of Quaternary deposits) beneath that point. The measurements employ a recording seismograph system that is implanted into the ground surface and records ambient ground vibrations in three orthogonal directions (2 horizontal and 1 vertical) during a 16-minute interval. The method is called passive because no energy is directly input into the ground at the time of measurement, such as is the case for conventional seismic sounding. Instead, the unit measures background vibrations from a variety of natural and artificial sources that include machinery, traffic, and wind. The averaged horizontal spectra of the seismic noise is divided by the corresponding vertical spectrum, and the resulting Horizontal to Vertical Spectral Ratio (HVSR) should display a prominent peak that closely approximates the resonant frequency (shear wave) of the unconsolidated sequence overlying the bedrock surface. The resonant frequency of unconsolidated overburden is a useful parameter for seismic risk investigations, but here it is used to estimate the thickness of the overburden itself, which in our case is the Quaternary sequence. In this application, the HVSR method is calibrated by taking measurements at locations where the thicknesses of Quaternary deposits are known from either well data or from conventional seismic sounding. The control points are selected to approximately span the expected range of bedrock depths for the region, and the calibration curve that is fitted to these data can be used to estimate bedrock depth in areas lacking either drill hole or seismic control. In general, depth to bedrock calculated by this method can have errors up to 25 percent of the depth; however, in areas with little to no other data, this is still useful information and many soundings can be inexpensively collected over a short period of time by one or two operators.
Seismic refraction soundings measure the time required for sound or pressure waves to travel from a source through the subsurface and be refracted back to a receiver. Travel time can be correlated with the density and rigidity of the geologic material. Precambrian and Paleozoic rocks usually exhibit pressure-wave velocities that are 1.5 to 2.5 times those of unconsolidated Quaternary sediments below the water tables. The spacing of the receivers (geophones) and the arrival times (measured in milliseconds) are used to calculate the depth to bedrock. Seismic refraction soundings are more labor intensive than passive seismic soundings, but can provide velocity information and higher-quality depth estimates. No seismic refraction soundings were acquired for the Isanti County Geologic Atlas, but the results of five soundings that were previously acquired by H.M. Mooney of the University of Minnesota were included.
DATA-BASE MAP
By
Margeurite C. Pettus and V.W. Chandler
2017
MINNESOTA GEOLOGICAL SURVEYHarvey Thorleifson, Director
Prepared and Published with the Support of THE ISANTI COUNTY BOARD OF COMMISSIONERS,
THE MINNESOTA ENVIRONMENT AND NATURAL RESOURCES TRUST FUNDAS RECOMMENDED BY THE LEGISLATIVE-CITIzEN COMMISSION ON MINNESOTA RESOURCES,
AND THE MINNESOTA LEGACY AMENDMENT'S CLEAN WATER FUND
Every reasonable effort has been made to ensure the accuracy of the factual data on which this map interpretation is based; however, the Minnesota Geological Survey does not warrant or guarantee that there are no errors. Users may wish to verify critical information; sources include both the references listed here and information on file at the offices of the Minnesota Geological Survey in St. Paul. In addition, effort has been made to ensure that the interpretation conforms to sound geologic and cartographic principles. No claim is made that the interpretation shown is rigorously correct, however, and it should not be used to guide engineering-scale decisions without site-specific verification.
COUNTY ATLAS SERIESATLAS C-44, PART A
Isanti County Plate 1—Data-Base Map
coNtoUr INtErval 10 MEtErS
1 0 1 2 3 4 5 MILES
8 KILOMETERS
SCALE 1:100 000
1 0 1 2 3 4 5 6 7
locatIoN DIaGraM
GEOLOGIC ATLAS OF ISANTI COUNTY, MINNESOTA
Digital base modified from the Minnesota Department of transportation BaseMap data; digital base annotation by the Minnesota Geological Survey.
Elevation contours were derived from the U.S. Geological Survey 30-meter Digital Elevation Model (DEM) by the Minnesota Geological Survey.
Universal transverse Mercator Projection, grid zone 151983 North american Datum
©2017 by the regents of the University of Minnesota
the University of Minnesota is an equal opportunity educator and employer
GIS compilation by M.c. PettusEdited by lori robinson
INTRODUCTION
The public health and economic development of Isanti County are directly dependent on the wise use and management of its land and water resources. Geologic and hydrologic information are essential before decisions are made that affect natural resources. Although the amount of geologic information required for making specific decisions can vary, the information will not be used if it is unavailable when needed, or if it is available only in a highly technical form, or scattered in many different maps and reports. The data bases described here address this need.
County atlases, prepared jointly by the Minnesota Geological Survey and the Minnesota Department of Natural Resources, present detailed geologic and hydrologic information in an interpretive as well as descriptive form. Maps and texts summarize basic geologic and hydrologic conditions at a county scale, and interpret these conditions in terms of the impacts of possible land- and water-use decisions. Site-specific information is available in some areas at a greater level of technical detail than shown on the maps of this atlas. The data are too voluminous to present at the scale of this atlas, but have been incorporated into readily accessible files housed at the Minnesota Geological Survey.
Several sources commonly provide information about an area or an individual property, but they may use different classification schemes to describe the same geologic materials. As a result, discrepancies in interpreting the data may arise or the different sources may appear to contradict each other. For example, water-well drillers may describe glacial till as "clay," but engineering records will describe it as "clayey sand." Both descriptions are acceptable for their original purpose of describing the physical attributes of the material. "Clay," the term used by well drillers, defines the general inability of the till to yield groundwater to a well. "Clayey sand," the term from the engineering record, defines the physical composition of the till relative to particle size and engineering properties. The geologist must take the analysis one step further and define the material in terms of how it formed rather than how it is to be used. In this example, till consists of an unsorted mixture of rock fragments ranging in size from clay to cobbles and boulders, and it is interpreted by the geologist as having been deposited directly by glacial ice. Understanding the process by which the material formed allows geologists to make predictions about what lies between and beyond data points.
All of the types of data described on this plate were interpreted by geologists or hydrogeologists to make them meaningful for mapping purposes. The 1:100,000 scale of the maps in this atlas was chosen because it shows the geologic and topical studies of the county while keeping the physical size of each plate to a manageable level. As a result, some detailed information that was gained by data interpretation and mapping cannot be shown on these maps or discussed in the texts. Some of this information is available in digital files that accompany the atlas.
Whether to use the atlas alone, or in combination with the data bases, depends on the amount of detail needed. Generally, data-base information must be used to evaluate site-specific conditions.
DATA-BASE MANAGEMENT
All of the data shown on the map were plotted on 7.5-minute topographic quadrangle maps or highway alignment maps and assigned inventory numbers. Automated data bases and a few manual files were developed to provide easy access and rapid retrieval of these site-specific data. The data may be obtained from the Minnesota Geological Survey.
Computer storage and retrieval systems are better than manual files for manipulating large amounts of data because automated geologic data bases can be designed to interact with other computer files, such as land-use data. Such interaction permits more efficient assessment of cause-and-effect relationships concerning natural resources than is commonly possible with manual files.
ISANTI COUNTY DATA BASES
Computerized files were developed for point-source data such as wells and borings in Isanti County. They use Public Land Survey descriptions, Universal Transverse Mercator (UTM), and latitude-longitude coordinates as location criteria; thus, they are compatible with the natural-resource data bases housed at the Minnesota Land Management Information Center (LMIC). The computerized data base developed for Isanti County by the Minnesota Geological Survey is the County Well Index (CWI).
County Well Index (CWI)—Information from water-well records and exploration holes is entered into this statewide data base. Each well log is assigned a six-digit unique number and each exploration drill hole is assigned either a five- or six-digit unique number. These reference numbers are also used by state agencies and the Water Resources Division of the U.S. Geological Survey. Elevations, expressed in feet above sea level, were determined either from topographic maps (see the index to 7.5-minute quadrangles) or Minnesota's lidar high-resolution elevation data set. Elevations from the topographic maps are generally accurate to plus or minus 5 feet (1.5 meters), and the lidar elevations are generally accurate to within 3 feet (1 meter). The street address of each well is also included wherever possible to provide data users with a well-location system that is compatible with local regulatory programs. Software at the Minnesota Geological Survey is used to display and tabulate many of the data elements contained on the original well log.
The County Well Index is currently stored in a data base that consists of ten related tables. These tables contain information such as well depths, well construction, addresses, aquifers, dates drilled, static water levels, and pumping test data. They also contain alternate well identifiers such as permit numbers or emergency-service numbers, the well stratigraphy (the geologic materials encountered during drilling), and the azimuth and inclination of angled exploration holes.
CWI application software developed by the Minnesota Department of Health provides two types of reports:
WELL LOG contains all the information about the well as it was reported by the contractor (Fig. 1). There may also be additional location information, land-surface elevation, aquifer designation, and remarks about the drill hole.
WELL STRATIGRAPHY contains the geologic log with a geologist's stratigraphic interpretations, which are based on her or his knowledge and understanding of the geology of Isanti County and augmented in some cases by additional data sources, such as cuttings, borehole geophysical logs, or core (Fig. 2). Only those drill holes with verified locations have stratigraphy assigned to them.
File data of the Minnesota Geological Survey—Details about other types of data shown on this plate are available from digital (including the Quaternary Data Index, an internal working data base) and paper files at the Minnesota Geological Survey. These include descriptions of cutting samples, soil borings, Giddings probe holes, field sites, soil auger holes, textural analyses, gravity and aeromagnetic data, passive seismic sites, and aggregate resources sites.
FUTURE DATA COLLECTION
Additional geologic information is generated continuously as new water wells are drilled, construction activities expose more bedrock, or additional wells are tested for water quality. To address this, the library of information prepared for Isanti County is flexible so that old data can be reevaluated in light of new information, and new forms of data can be added if required. The need to manage groundwater and other natural resources wisely will never become outdated. Future demands on these resources will require current data to assess the impacts.
ACKNOWLEDGEMENTS
The staff from the Isanti Soil and Water Conservation District and the staff from the City of Cambridge contributed greatly to the development of the County Well Index (CWI) data base. We thank local water-well contractors and landowners for their assistance.
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INDEX TO 7.5-MINUTE QUADRANGLES
County
Well NameRange DirTownship Section Subsection
Well Depth Depth Completed Date Well Completed
Update DateIsanti
DNR OB 30016
25 W 35 DDDCDD36
No
262.00 262.00 2010/09/10ft ft
Make
Static Water Level
Open Hole(ft.) From
Last Strat
g.p.m.hrs. pumpting
Grouting Information
Capacity
Well disinfected upon completion?
Pump
Variance
Abandoned Wells
Screen
Nearest Known Source of Contamination
Well Contractor Cerfication
BRIAN & TONY
üü
ü
ü
230.0 262.0
Quad
Depth to Bedrock
Pumping Level (below land surface)
Model
153C
961.00
1404
Mt.Simon-Hinckley
Pitless adapter manufacturer
ft.
Well grouted?
feet Direction Type
Printed on
Model number
Manufacture's name
REPORT
Type
Wellhead Completion
ü
300 S BYD
210.00
MN DNR500 LAFAYETTE RD
55155ST PAUL MN Changed
contact address
DNR SPECTACLE SITE 39 CR
MN
well address
MINNESOTA DEPARTMENT OF HEALTH
MINNESOTA STATUTES CHAPTER 1031WELL AND BORING RECORD
Description From To (ft.)Color HardnessFINE SAND V.SOFT TAN 180
COARSE SAND & GRAVEL SOFT 3018
CLAY TILL MEDIUMGRAY 4530
FINE SANDS SOFT BRN/TAN 7045
COARSE SAND & GRAVEL SFT-MED 14070
COARSE SAND & GRAVEL SOFT 194140
CLAY SOFT BROWN 199194
COARSE SAND & GRAVEL TAN 209199
MT. SIMON SANDSTONE SFT-MED YELLOW 210209
MT. SIMON SANDSTONE SFT-MED YELLOW 251210
HINCKLEY SANDSTONE HARDRED 252251
HINCKLEY SANDSTONE HARDRED 262252
RemarksGAMMA LOGGED 9-2-2010. M.G.S. NO. 5022. LOGGED FOR DNR.LOGGED IN 10 IN. DIAMETER BOREHOLE. SPECTACLE LAKE WMA(SP). USE = ENV BORE HOLE PER MEMO DATED 9/26/2011.WELLHEAD COMPLETION: CASING PROTECTION= PROTOP &BUMPER POSTS. DRILLERS: BRIAN TRAUT & TONY NOVAK. DNRGEOLOGIST ON SITE FOR SAMPLING.
HE-01205-07 (Rev. 2/99)Date
Lic. or Reg No.
Mark J Traut Wells, Inc.
Was a variance granted from the MDH for this well?
Does property have any not in use and not sealed well(s)?
11/15/2016
dellatsnI etaDdellatsnI toN
Type
Length of drop pipe
HP Volts
g.p.m
To 262.010.004.00 in. from to 230.000.00 ft. 10.79 lbs/ft
to
neat cement 0.0 230.0 7.25oTmorFlairetaM ft. Cubic yards
Hole Diameter (in.)
Elevation
At-grate (Environmental Wells and Borings ONLY)
Casing Protection 12 in. above grade
Basement offset
üYES NO
YES NOü
YES NO
YES NO
ft. after
Date measured
Material
Diamter Length SetSlot
2010/09/1034.50 land surface
2010/09/022014/08/072010/11/01
Entry Date
Received Date
Unique Well Number
County Well Index v.5
Aquiferft.
First Bedrock CMTSPMHN
Field Locatedft.
Quad Id
MGS
779947 Wyanett
License Business Name
Name of Driller
Diameter 4 Depth 230Casing Type Steel (black or lowDrive Shoe? YES NO
Use environ. bore hole
WaterDrilling Fluid Well Hydrofractured? YES ü NO
From ft. to
Drilling Method Dual Rotary
DrillholeAngle
NOT SPECIFIED
Figure 1. Example of a WELL LOG record, showing all the information about the well as reported by the well driller.
Digitization (Screen) - Map (1:24 000)
Unique Well Number County Isanti
riDegnaRemaN lleW Township Section Subsection Depth Drilled Depth Completed Lic/Reg. No.Date Completed
QuadQuad Id
DNR OB 30016 25 W 35 DDDCDD36 262 262ft ft 14042010/09/10
Elevation 961.00 ft. Open Hole 230-262Method 7.5 minute topographic Aquifer Mt.Simon-Hinckley Depth to Bedrock 210 ft.
Field LocatedProgramUni No.Verified
Location MethodInput SourceInput Date
Universal Transverse Mercator(UTM) - NAD83 - Zone 15 - MetersUTM Northing (Y)UTM Easting (X)
467925 50450492010/09/02
Wyanett
2010/09/022014/08/072010/11/01
Entry DateUpdate DateReceived Date
MINNESOTA DEPARTMENT OF HEALTHWELL AND BORING RECORD
MINNESOTA STATUTES CHAPTER 1031
Driller NameBRIAN & TONY
SWL 34.5
779947
Information from owner
Minnesota Geological SurveyMinnesota Geological Survey
Geological Material MinorSecondaryDEPTH
PrimaryELEVATION LITHOLOGY
Hardness StratigraphyFrom To Thick From ToColor
John Mossler MGS Geologic study 1:24k to 1:100kycnegAnoitaterpretnI cigoloeG Interpretation Method
153C
FINE SAND TAN V.SOFT 18 sand-brown sand18 961 9430
COARSE SAND & GRAVEL gravelSOFT 30 sand +larger sand12 943 93118
CLAY TILL clayGRAY MEDIUM 45 till-gray till15 931 91630
FINE SANDS BRN/TAN SOFT 70 sand-brown sand25 916 89145
COARSE SAND & GRAVEL gravelSFT-MED 140 sand +larger sand70 891 82170
COARSE SAND & GRAVEL gravelSOFT 194 sand +larger sand54 821 767140
CLAY BROWN SOFT 199 clay-brown clay5 767 762194
COARSE SAND & GRAVEL gravelTAN 209 sand +larger-brown sand10 762 752199
MT. SIMON SANDSTONE gravelYELLOW SFT-MED 210 sand +larger sand1 752 751209
MT. SIMON SANDSTONE YELLOW SFT-MED 251 Mt.Simon Sandstone sandstone41 751 710210
HINCKLEY SANDSTONE RED HARD 252 Mt.Simon Sandstone sandstone1 710 709251
HINCKLEY SANDSTONE RED HARD 262 Hinckley Sandstone sandstone10 709 699252
Figure 2. Example of a WELL STRATIGRAPHY record, which contains a geologist's interpretation of the geologic materials listed by the driller in the WELL LOG record (Fig. 1). Additional downhole information for this well (as noted in the Interpretation Method on the record above) controls the geologist's interpretation, which may not match the driller's description of the geologic material penetrated.
Note: More than one symbol can occur at the same location
Record of water-well construction (well driller's log)
Diamond drill core sample
Rotary-sonic core sample
Cutting sample
Borehole geophysical log
Soil boring
Giddings probe hole
Field site
Textural analysis
Gravity data
Passive seismic sounding
Seismic refraction sounding
MAP SYMBOLS
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ENVIRONMENTAND NATURAL RESOURCES
TRUST FUND
