Lithogeochemical features of Riphean fine-grained terrigenous rocks in the Kama-Belaya aulacogen and...

ISSN 0024�4902, Lithology and Mineral Resources, 2010, Vol. 45, No. 2, pp. 172–200. © Pleiades Publishing, Inc., 2010.Original Russian Text © A.V. Maslov, M.V. Isherskaya, M.T. Krupenin, V.G. Petrishcheva, T.Ya. Gulyaeva, N.P. Gorbunova, 2010, published in Litologiya i Poleznye Iskopaemye,2010, No. 2, pp. 192–223.

The Kama–Belaya (Kaltasy or Osa–Bir) aulaco�gen is one of the largest Riphean structures in the east�ern East European Platform. Its sedimentary sequencerepresented by terrigenous and carbonate rocks is 10–12 km thick, which is comparable with the thickness ofthe standard Riphean section in the Bashkir anticlino�rium (‘meganticlinorium,’ according to Uralian geol�ogists) on the western slope of the South Urals.

Analysis of geophysical materials (Lozin andKhasanov, 1991a, 1991b; Lozin, 1994; Berzin et al.,1996; Carbonell et al., 1996; Echtler et al.,1996; Glu�binnoe.., 2001) and deep drilling (Isherskaya andRomanov, 1993; Verkhnii…, 1995; Belokon et al.,2001; Romanov and Isherskaya, 2001) and lithologi�cal–paleogeographic reconstructions (Aliev et al.,1977; Postnikova, 1977; Lagutenkova and Chepikova,1982; Maslov, 1994, 1995, 1997; Maslov and Isher�skaya, 1998, 2002; Maslov et al., 2002) revealed thatsedimentary sequences filling the Kama–Belaya aula�cogen are replaced in the eastern direction by Ripheansedimentary successions of the Bashkir anticlinorium.

Therefore, there are grounds to assume that the sedi�ments were formed in common sedimentary basin(s).At the same time, different models are used so far toexplain the accumulation of Riphean rocks on thewestern slope of the South Urals and Kama–Belayaaulacogen. First attempts of their unification based onsmall�scale lithological–paleogeographic reconstruc�tions were undertaken in our works (Maslov, 1994,1995, 2000; Maslov and Isherskaya, 2002; Maslovet al., 2002). In this work, we present the results ofanalysis of lithogeochemical features of Riphean fine�grained terrigenous rocks in the Kama–Belaya aula�cogen. The aim of our work was to compare theobtained data with both materials of previous mineral�ogical–petrographic studies (pertaining to recon�struction of rock composition in provenances) anddata on the typical Riphean section (Maslov et al.,2003b, 2004a, 2004b, 2004c, 2006, 2007). We shouldemphasize here the following point: combined withtraditional lithological observations, our practicalexperience and data reported in (Interpretatsiya …,

Lithogeochemical Features of Riphean Fine�Grained Terrigenous Rocks in the Kama–Belaya Aulacogen and Their Formation

ConditionsA. V. Maslova, M. V. Isherskayab, M. T. Krupenina, V. G. Petrishchevaa,

T. Ya. Gulyaevaa, and N. P. Gorbunovaa

aInstitute of Geology and Geochemistry, Uralian Division, Russian Academy of Sciences, Pochtovyi per. 7, Yekaterinburg, 620075 Russia

e�mail: maslov@igg.uran.rubInstitute of Geology, Ufa Scientific Center, Russian Academy of Sciences, ul. Karla Marksa 16/2, Ufa, 450000 Russia

Received September 8, 2008

Abstract—Lithogeochemical features of Riphean fine�grained terrigenous rocks of the Kama–Belaya aula�cogen are discussed. It is shown that aluminosiliciclastic material delivered to the aulacogen during the Riph�ean was characterized by a low maturity degree. The successively increasing K2O/Al2O3 values in the Ripheansummary section correlate negatively with the CIA index values, indicating a gradually strengthening ten�dency for climate aridization in erosion zones. Data on some indicator ratios of trace elements and REE sys�tematics in Riphean silty mudstones and shales of the Kama–Belaya aulacogen imply the involvement ofmafic and ultramafic rocks, in addition to acid igneous and metamorphic varieties, in erosion during accu�mulation of the Nadezhdino, Tukaevo, Ol’khovka, Usinsk, and Priyutovo formations. Comparison of dataon the composition of rocks in provenances based on the mineralogical–petrographic study of sandstones andinvestigation of geochemical features of silty mudstones and shales revealed their sufficiently high similarity.The geochemical data made it possible to specify the composition of rocks in provenances. Low Ce/Cr valuesin the fine�grained terrigenous rocks of the Lower Riphean Kyrpy Group suggest their formation with a sig�nificant contribution of erosion products of the Archean substrate, which is atypical for higher levels of thesection. Thus, the Early–Middle Riphean transition period was likely marked by substantial changes in themineral composition of material delivered to the Kama–Belaya aulacogen. The lack of exhalative compo�nents in the examined specimens of silty mudstones and shales points to a relatively low permeability of theEarth’s crust in the eastern East European Platform through the entire Riphean.

DOI: 10.1134/S0024490210020069

LITHOLOGY AND MINERAL RESOURCES Vol. 45 No. 2 2010

LITHOGEOCHEMICAL FEATURES 173

2001; Geochemistry…, 2003) demonstrate that theanalysis of lithogeochemical features of the fine�grained terrigenous rocks provides rather consistentinsights into different factors governing processes ofthe formation of sedimentary sequences to a variableextent.

RIPHEAN LITHSTRATIGRAPHY OF THE KAMA–BELAYA AULACOGEN

The Kama–Belaya aulacogen located east of theTatar Arch extends in the meridional direction over600–700 km and its width is approximately 150–200 km(Fig. 1). In north, it is bordered by a regional system ofNE�trending faults in the basement (Belokon et al.,2001). Its eastern boundary is represented by theOsintsevo–Krasnoufimsk basement Swell. TheOr’ebash–Chernusha sublatitudinal dislocation zonedivides the Kama–Belaya aulacogen into the northern(Kama) and southern (Belaya) depressions. The KamaDepression is dominated by Lower Riphean rocks,while the Belaya Depression is filled with terrigenousand carbonate rocks of all three main Riphean strati�graphic units: Burzyanian, Yurmatinian, and Karata�vian (Stratigraficheskaya…, 2000).

The characteristics of different intervals of theRiphean section recovered by deep boreholes in theKama–Belaya aulacogen is given in many works(Ivanova et al., 1969; Ivanova, 1970; Aliev et al., 1977;Postnikova, 1977; Andreev et al., 1981; Lagutenkovaand Chepikova, 1982; Ozhiganova, 1983; Stratotip…,1983; Isherskaya and Romanov, 1993; Lozin, 1994,1999; Romanov and Isherskaya, 1994, 1998, 1999,2001; Aksenov, 1998; Maslov and Isherskaya, 1998;Stratigraficheskaya …, 2000; Masagutov, 2002; Maslovet al., 2002). Therefore, we provide only brief informa�tion necessary for the further discussion of materials.

The Lower Riphean section of the Kama–Belayaaulacogen is represented by the Kyrpy Group, which

comprises the Prikamsk1. Kaltasy, and Nadezhdino

formations (Maslov and Isherskaya, 1998). The mostcomplete sections of the group are recovered by deepand superdeep boreholes drilled in the northwesternpart of the aulacogen (Isherskaya and Romanov, 1993;Masagutov, 2002; Ozhiganova, 1983; Romanov andIsherskaya, 1998, 2001).

The Prikamsk Formation (R1prk), which overliesthe crystalline basement, is composed of variegatedand red sandstones, gravelstones, and siltstones. Theupper part is dominated by fine�grained rocks with

1 The basal layers of the Riphean section in the Kama–Belaya aulaco�gen are characterized by a complex structure and subdivided byresearchers into different lithostratigraphic units (Belokon et al.,2001; Romanov and Isherskaya, 2001; Masagutov, 2002; Strati�graficheskaya …, 2000; Verkhnii …, 1995). Therefore, when consider�ing geochemical features of Riphean fine�grained terrigenous rocks,we use for the convenient perception of materials the term “PrikamskFormation” for all terrigenous rocks older than Kaltasy Formation asin (Belokon et al.,2001).

carbonate admixture. According to (Isherskaya andRomanov, 1993; Maslov and Isherskaya, 1998), thesummary section of the Prikamsk Formation includesthe following four subformations (from bottom totop): (i) the Azyakul Subformation is composed offine� to coarse�grained, pinkish to pinkish gray, quartzand feldspar–quartz sandstones; (ii) the Norka Sub�formation is mostly composed of red�brown and darkviolet silty mudstones and feldspar–quartz or subar�kosic siltstones, while fine�grained feldspar–quartzsandstones and marls are subordinate; (iii) the Rotk�ovo Subformation is represented by fine�grained andinequigranular red�colored feldspar–quartz andquartz sandstones with the subordinate share of grav�elstones, conglomerates, siltstones, and shales; and(iv) the Minaevo Subformation is composed of varie�gated feldspar–quartz siltstones, dolomites, marls,gravely�pebbly rocks, shales, and silty mudstones.Total thickness of the Prikamsk Formation varies from100 to 1800 m. The K–Ar isotopic dating of mineral�ogically unstudied glauconite from sandstones of thePrikamsk Formation yielded 1542 ± 18 Ma (BoreholeMenzelino�Aktanysh 203) and 1520–1425 Ma (Bore�hole Buraevo 3) (Stratotip…, 1983). Isotopic age of thefine�grained rocks from the same stratigraphic level ofthe Kyrpy Group is estimated at 1482 ± 15 to 1408 ± 14 Ma(Rb–Sr method, fraction <0.001 mm) (Gorozhanin,1983).

The Kaltasy Formation (R1klt) (60–300 m thick) ismainly composed of dolomites with the subordinateshare of detrital rocks (sandstones, siltstones, and siltymudstones) confined to its middle (Arlan) subforma�tion. Carbonate rocks at this Lower Riphean level arecharacterized by the wide development of microbialand fenestra structures and cementation�crustifica�tion sulfate rims in flakestones, and the presence ofoncolite and stromatolite interbeds. All these featuresimply the accumulation of primary sediments inextremely shallow settings periodically resemblingsebkhas (Michurin, 2008). The thickness of the Kal�tasy Formation (3000–3500 m) is maximal in the cen�tral Kama–Belaya aulacogen and does not exceed afew tens of meters at the northern periphery (Frolov�ich, 1980; Isherskaya and Romanov, 1993). Accordingto (Kazakov et al., 1967; Stratotip…, 1983), isotopicage of authigenic glauconite from the Kaltasy Forma�tion is 1470–1490 Ma (K–Ar method).

The Nadezhdino Formation (R1nd) (150–730 mthick) comprises variegated sandstones, siltstones, andsilty mudstones with gravelstone and conglomerateinterbeds. Its lower part is dominated by the fine�grained terrigenous and carbonate–terrigenous rocks.The K–Ar age of gabbro�dolerite intrusions in thisformation is ~1370 Ma (Stratotip…, 1983). The Kaba�kovo Formation (greenish gray to dark gray silty mud�stones, siltstones, and carbonate rocks) defined withinthe Lower Riphean section by S.G. Morozov and

MASLOV et al.

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Fig. 1. (a) Schematic structure of the Kama–Belaya aulacogen; (b, c) sublatitudinal geological profiles 1–1' and 2–2', respec�tively, across the aulacogen, based on (Belokon et al., 2001); and position of some parametric and exploration boreholes thatrecovered Riphean rocks. (1) Areas lacking Lower Riphean rocks; (2) western boundary of the area lacking Upper Precambrianrocks; (3) western boundary of the field of Middle and Upper Riphean rocks; (4) boundary between (a) formations and (b) frac�tures; (5) isopachs of Riphean rocks; (6) boreholes; (7) western boundary of the Uralian foldbelt; (8) study region.(AR–PR1) Archean–Early Proterozoic crystalline rocks of the basement; (R1) undivided Lower Riphean rocks; formations:(prk) Prikamsk, (klt) Kaltasy, (nd) Nadezhdino, (kb) Kabakovo, (tk) Tukaevo, (ol) Ol’khovka, (us) Usinsk, (prt) Priyutovo,(sh) Shikhany; (V2) Upper Vendian; (PZ) Paleozoic.Boreholes: (3�KK) Kopei�Kubovo 3, (2�S) Sauzbash 2, (7000�Ar) Arlan 7000, (82�Or) Or’ebash 82, (203�B) Bedryazh 203, (1�D) Dorokhvakaya 1, (5�M) Manchazh 5, (10�B) Bukharovskaya 10, (62�K) Kabakovo 62, (1�S�Ksh) Severo�Kushkul 1, (1�Kp)Kipchak, (740�Shk) Shkapovo 740), (203�M–A) Menzelino�Aktanysh 203, (20005�M–A) Menzelino�Aktanysh 20005, (20007�Su) Sulli 20007.(I) Kama–Belaya aulacogen; (II) Sernovodsk–Abdula aulacogen; (III) Kvarkusha–Kamennogorsk anticlinorium; (IV) Bashkiranticlinorium.

T.V. Ivanova in the terminal 1970s is considered as theupper unit of the Nadezhdino Formation (Romanovand Isherskaya, 2001).

The Prikamsk and Kaltasy formations of the KyrpyGroup are correlated in the Riphean type section withthe Ai and Satka formations, respectively (Stratotip…,

1983; Isherskaya and Romanov, 1993; Maslov and Ish�erskaya, 1998). The Nadezhdino Formation corre�sponds to the Bakal or Moshak Formation (Romanovand Isherskaya, 1994).

The Middle Riphean section (SerafimovkaGroup), which transgressively overlies Lower Ripheanstrata, is represented by the Tukaevo and Ol’khovkaformations (Isherskaya and Romanov, 1993; Romanovand Isherskaya, 1994; Maslov and Isherskaya, 1998).The Tukaevo Formation (R2tk) (up to 630 m thick)includes mostly variegated arkosic and composition�ally similar sandstones with the subordinate share ofshales and siltstones. Glauconite from the Tukaevosandstones yielded the K–Ar age of 1253 ± 20 Ma and1274 ± 12 Ma (Isherskaya and Romanov, 1993; Maslovand Isherskaya, 1998). The Ol’khovka Formation(R2ol) (340–840 m) is represented by variegated siltymudstones, marls, siltstones, and dolomites. Its lowerpart also includes dark�colored siltstones and shalesconstituting the so�called Akberda Horizon (Andreevet al., 1981; Stratotip…, 1983). The K–Ar age of gab�bro–dolerite dikes intruding the Ol’khovka Formationvaries from 1138 to 1120 Ma (Stratotip…, 1983).

The Tukaevo Formation of the Kama–Belaya aul�acogen is correlated with the Zigal’ga Formation ofthe Bashkir anticlinorium, whereas the upper part ofthe Ol’khovka Formation corresponds to the Avzyanlevel of the Yurmatinian (Romanov and Isherskaya,1994; Maslov and Isherskaya, 1998; Maslov, 2000).According to most researchers, the Akberda Horizonmost likely correlates with the Zigaza–Komarovolevel of the Middle Riphean type section.

The Upper Riphean Abdula Group (Usinsk,Leonidovo, Priyutovo, and Shikhany formations)overlies with an erosional surface Middle and LowerRiphean rocks or, locally, the crystalline basement.The Usinsk Formation (R3us) (45–400 m) is com�posed of variegated and gray�colored feldspar–quartzand arkosic sandstones, siltstones, and silty mud�stones. According to (Isherskaya and Romanov, 1993;Romanov and Isherskaya, 2001), the Usinsk Forma�tion shows a gradual transition with the overlyingLeonidovo Formation (R3ln) (thickness 57–300 m ormore). The Leonidovo Formation is represented byvariegated to gray�colored quartz sandstones with thekaolinite cement. The Priyutovo Formation (R3prt)(76–676 m thick) unites variegated shales, siltstones,marls, dolomites, sandstones, and terrigenous–car�bonate rocks. The K–Ar age of mineralogicallyunstudied glauconite from sandstones of the PriyutovoFormation ranges from 843 to 896 Ma (Stratotip…,1983). The Shikhany Formation (R3sh) (0–360 m) iscomposed of gray�, green�, and red�colored clayeyand stromatolitic limestones (dominant), dolomites,and marls.

Rocks younger than the Shikhany Formation aremissing in both the Kama–Belaya aulacogen and theentire Volga–Urals region.

Based on the interpretation of seismic time sec�tions and some other materials, the Usinsk Formationmay be correlated with the Bir’yan–Nugush level inthe Upper Riphean Karatau Group of the Bashkiranticlinorium. The Leonidovo and Priyutovo forma�tions are correlated with the Lemeza and Bederyshsubformations, respectively, of the Zil’merdak Forma�tion. In terms of lithology, the Shikhany Formation issimilar to the Katav Formation (Rabochaya…, 1981;Isherskaya and Romanov, 1993; Romanov and Isher�skaya, 1994, 2001; Maslov and Isherskaya, 1998;Stratigraficheskaya …, 2000).

CONCEPTS OF THE SEDIMENTARY SEQUENCE FORMATION

IN THE KAMA–BELAYA AULACOGEN: AN OVERVIEW

Stratigraphic positions of various sequences in thepre�Vendian section of the Kama–Belaya aulacogen isa debatable issue. In addition, publications in the1950s–1970s are characterized by discrepancies in thecorrelation of these sequences with the Riphean stan�dard section and now we cannot correctly use many ofthe previously published lithofacies, paleotectonic,and paleogeographic reconstructions. Therefore, anoverview of only some previous concepts is givenbelow.

According to (Aksenov et al., 1984; Aksenov andSolontsov, 1986), the Kama–Belaya aulacogen origi�nated at the beginning of the Early Riphean. At earlystages of its development, fine�grained fluvial andlacustrine sediments of the lower part of the PrikamskFormation were accumulated in shallow depressions.In the second half of the Prikamsk time, a sharpincrease in subsidence rate and differentiated move�ment of blocks promoted the formation of ruggedrelief in provenances and the accumulation of mainlycoarse�detrital terrigenous rocks. The third stage(Kaltasy time) was marked by transgression in a shal�low sea basin, which acquired a regressive trend by theend of the Early Riphean. Further, sedimentation pro�ceeded mostly in shallow�marine settings.

Ivanova et al. (1993) assume that, after terminationof the Karelian folding phase at the beginning of theRiphean, the Sarmatian shield was disintegrated withthe formation of the spacious Kama–Belaya graben�type depression at the southeastern periphery of theEast European Platform. It was bordered by the Kras�noufimsk Swell of the Bashkir Arch, Al’met’evsk Swellof the Tatar Arch, and Orenburg Arch. In the EarlyRiphean, the sedimentary complex of the Agidel,Prikamsk, and Kaltasy formations (up to 10–12 kmthick in total) was deposited in the southeastern part ofthis depression. The deepest�water sediments wereaccumulated during the Kaltasy time. The general dif�ferentiated uplift of a significant part of the Kama–Belaya aulacogen in the terminal Early Riphean led todifferent degrees of erosion of Lower Riphean rocks at

MASLOV et al.

that time. In the Middle Riphean, the eastern EastEuropean Platform and western slope of the SouthUrals were occupied by a single sedimentation basin.In the Late Riphean, two zones of intense subsidenceappeared in the region under consideration: south�western (Sernovodsk–Abdula aulacogen) and south�eastern.

Belokon et al. (1994, 1995) consider the Kama–Belaya and Sernovodsk–Abdula troughs as a singlesystem with complex development history. In thesestructures, relative to underlying complexes, UpperRiphean rocks are substantially less distributed due tothe pre�Vendian and pre�Devonian erosion episodes,as well as specific features of synsedimentary tectonics.

According to (Lozin, 1994), a system of microriftswith dominant submeridional orientation was formedat the southeastern margin of the East European Plat�form during the Riphean. In the Early Riphean, theywere filled with deep�water sediments up to 8–11 kmthick. In the Middle Riphean, these microrift zoneswere transformed info the regional Khomutovo–Ufa–Teplaykovo Trough, which continued to develop in theinherited manner through the Late Riphean and Ven�dian. However, it is assumed that formation of thistrough in the Early Riphean was controlled signifi�cantly by processes in “…the newly forming Uraliangeosyncline” (Lozin, 1994, p. 30). Sedimentation ratein the Kama–Belaya aulacogen reached maximal val�ues in the Early Riphean and decreased gradually bythe end of this era. This was accompanied by reductionof the sedimentary basin due to expansion of the Tatarand Bashkir arches.

According to (Romanov and Isherskaya, 2001),development of the Kama–Belaya aulacogen virtuallyterminated by the end of the Middle Riphean. Thebeginning of late Riphean was marked by developmentof the Sernovodsk–Abdula aulacogen filled mainly bysediments of the Abdula Group.

Masagutov (2002) considers the Kama–Belayaaulacogen formation as a multistage process: recurrentrifting complicated significantly the regional struc�tural plan, which was formed in the initial Early Riph�ean, and promoted the appearance of several new gra�ben�shaped troughs. It is assumed that the Kama–Belaya aulacogen bordered in east in the Early Riph�ean with an oceanic basin with a well�developed islandarc. In the Middle Riphean, the Kama–Belaya aula�cogen was characterized by a terraced structure: itswestern wall represented a shelf zone, the eastern seg�ment of which was complicated by a system of troughs,grabens, and depressions. In the Late Riphean, sub�sidence area of the aulacogen was appreciablydecreased. Masagutov (2002) suggested that terrige�nous sediments were deposited before the Kaltasy timeunder conditions of warm humid climate in slightlyreducing and oxidizing settings. In the Kaltasy time,the basin was mostly characterized by stable reducingregime. The Nadezhdino Basin accumulated productsof underwater volcanism. The Tukaevo and Ol’khovka

epochs were characterized by hot humid climate,which stimulated the development of weatheringcrusts in paleodrainage areas. Sediments of theUsinsk, Leonidovo, and Priyutovo formations wereaccumulated in oxidizing and slightly reducing set�tings, while the Shikhany basin was dominated byreducing conditions.

The Tatar Arch, which is considered by mostresearchers as the main source of detrital pile in theRiphean Kama–Belaya aulacogen, is mostly com�posed of sediments of the Archean Otradnoe andBol’shaya Cheremshanka groups (Aliev et al., 1977;Bogdanova, 1986; Bogdanova et al., 2008). TheOtradnoe Group is composed of two�pyroxene–pla�gioclase, amphibole–pyroxene–plagioclase, biotite–garnet–hypersthene–cordierite, and biotite–garnetcrystalline schists and gneisses accompanied byamphibolites, amphibole–pyroxene, biotite–amphibole, biotite, and biotite–garnet plagiogranites,peridotites, gabbro, gabbronorites, norites, andanorthosites. The Bol’shaya Cheremshanka Groupincludes biotite–garnet–sillimanite–cordierite andbiotite–garnet–hypersthene–cordierite plagiog�neisses, as well as two�pyroxene crystalline schists,with local amphibolites, charnockites, and garnet�bearing granites. The Lower Proterozoic Sarmanovo(amphibolites, biotite–garnet schists, jaspilites, andmicrocline granites) and Vorontsovo (biotite and acti�nolite schists, granites, and syenites) groups are subor�dinate in the Tatar Arch.

The mineralogical–petrographic features of Riph�ean sandstones from the Kama–Belaya aulacogen areanalyzed in (Timergazin, 1959; Ozhiganova, 1960,1983; Ivanova et al., 1969; Aliev et al., 1977; Laguten�kova and Chepikova, 1982; Verkhnii…, 1995). Theheavy fraction from Riphean terrigenous rocks in thewestern zone of the aulacogen includes more than 30accessory minerals dominated by the universally mostwidespread zircon, apatite, and tourmaline (Verkh�nii…, 1995). The Lower Riphean Prikamsk sandstonescontain up to 85–98% of quartz and 2–15% of feld�spar (mostly microcline and orthoclase). The assem�blage of their accessory minerals is “…very poor”(Aliev et al., 1977, p. 19) and represented by the dom�inant black ore minerals (up to 44%), zircon (up to32%), and tourmaline (up to 16%). Apatite, musco�vite, sillimanite, corundum, hornblende, sphene, andgarnet are subordinate. As a whole, mineral assem�blages from sandstones of the Prikamsk Formationindicate the development of different acid igneous andmetamorphic rocks in provenances (Verkhnii…, 1995).In sandstones from the Arlan Subformation (KaltasyFormation), feldspars are dominated by plagioclases.Their heavy faction is mainly composed of muscoviteand characterized by a lower content of dark ore min�erals as compared with the Prikamsk level.

The Middle Riphean Tukaevo sandstones is domi�nated by quartz (up to 72–94%). The content ofmicrocline and orthoclase varies from 5 to 30%. Their

heavy fraction is mostly represented by black ore min�erals. Mineral assemblages from this stratigraphic levelpoint to the prevalence of acid igneous and metamor�phic rocks in provenances. At the same time, presenceof magnetite, pyroxene, and chrome spinels impliesthe development of mafic and ultramafic rocks inpaleodrainage areas (Verkhnii…, 1995). In psammitesof the Ol’khovka Formation, the content of micro�cline and orthoclase varies from 32 to 45%. The subor�dinate heavy fraction is dominated by micas and darkore minerals accompanied by minerals common foracid rocks: zircon, apatite, tourmaline, kyanite, andcorundum.

Like in the underlying rocks, the assemblage ofaccessory minerals in sandstones of the Upper Riph�ean Usinsk Formation usually consists of zircon, apa�tite, tourmaline, and micas, while rutile, leucoxene,amphibole, garnet, and epidote subordinate. Mineralsindicating development of mafic and ultramafic rocksin paleoprovenances (magnetite and pyroxene) occurat this stratigraphic level as occasional grains. In sand�stones of the Leonidovo Formation, the quartz con�tent ranges from 93 to 99%; accessory minerals aremostly represented by ilmenite and magnetite (up to60%), as well as the subordinate leucoxene (~8%), zir�con (8–15%), tourmaline, and micas. The notablecontent of detrital hematite and subangular magnetitegrains at this level indicates proximity of the prove�nance (Verkhnii…, 1995). The assemblage of accessoryminerals in the Leonidovo Formation is “…very poor”(Aliev et al., 1977, p. 36). Study of the heavy fractionfrom Riphean terrigenous rocks in the western (proxi�mal) part of the Kama–Belaya aulacogen revealed that“…mineral assemblages are similar in Lower and Mid�dle Riphean rocks,” while Upper Riphean rocks“… differ sharply by the substantially zircon composi�tion of the mineral assemblage” (Verkhnii…, 1995,pp. 132–133).

The observations described above demonstrate thefollowing point: despite significant closeness of prove�nances to sedimentation zones in our case, the terrig�enous–mineralogical assemblages are commonly rep�resented by very stable minerals, which likely experi�enced multiple recycling during sedimentation.Therefore, inferences about the composition of rocksin provenances based on such data are not quite reli�able. Analysis of lithogeochemical features of the fine�grained terrigenous rocks is among the additionalresearch tools required to make more confident con�clusions.

LITHOGEOCHEMICAL FEATURES OF THE FINE�GRAINED TERRIGENOUS ROCKS AS A SOURCE OF INFORMATION

ON FORMATION CONDITIONS OF SEDIMENTARY SEQUENCES

Data on the chemical composition and values ofsome indicator ratios of accessory elements in the

fine�grained terrigenous rocks (clays, mudstones, siltymudstones, and shales) yield information on weather�ing in paleodrainage areas, composition of erodedrocks, and some other sedimentation parameters(Taylor and McLennan, 1985; Interpretatsiya…, 2001;Maslov, 2005). For example, paleoclimate reconstruc�tions are based on lithochemical data derived from thestudy of the maturity degree of fine�grained alumino�siliciclastic material delivered to the basin from pale�odrainage areas. It is considered that the weatheringmode in provenances may be estimated using the fol�lowing geochemical parameters: hydrolyzate module,HM = (Al2O3 + TiO2 + Fe2O3 + FeO + MnO)/SiO2;alumina�silica module, AM = Аl2О3/SiO2; chemicalindex of alteration, CIA = 100 Al2O3/(Al2O3 +CaO* + Na2O + K2O); chemical index of weathering,CIW = 100 Al2O3/(Al2O3 + CaO + Na2O); and index

of compositional variability2 ICV = (Fе2О3 +

К2О + Nа2О + CaO + MgO + ТiO2)/Al2O3). Therocks with higher HM and AM values are consideredas materials consisting of components that experi�enced stronger weathering in paleodrainage areas(Yudovich, 1981; Yudovich and Ketris, 2000; Interpre�tatsiya …, 2001). According to (Nesbit and Young,1982; Visser and Young, 1990), the CIA value isapproximately 50 in fresh igneous rocks and can be ashigh as 100 in strongly weathered rocks. The CIA valueof 70 is accepted as the boundary between sedimentsaccumulated under the humid and arid (or nival) cli�mate conditions. The CIW value increases with thegrowth of rock decomposition degree in paleodrainageareas: from 59 to 76 in slightly altered basalts and gran�ites (Harnois, 1988) and from 94 to 98 in these rocksfrom weathering crusts. Fine�grained terrigenousrocks with high concentrations of clay�free silicateminerals are characterized by the ICV value of >1,while mature clayey rocks are characterized by theICV value of <1 (Cox et al., 1995).

Analysis of some indicator ratios of accessory ele�ments (for example, La, Th, Co, Se, Cr, Ni, V, Zr, andothers), which are typical of the fine�grained terrige�nous rocks, is considered one of the efficient methodsfor reconstructing the composition of rocks in paleod�rainage areas, because it is believed that contents ofthese elements and their ratios in clayey rocks remainpractically unchanged during lithogenesis and meta�morphism. The above�mentioned elements are poorlysoluble in water. Therefore, they are transported fromprovenances to the sedimentation basins almost with�out losses (Nesbitt, 1979; Davis, 1980; Taylor andMcLennan, 1985; Wronkiewicz and Condie, 1987;McLennan, 1989; Condie and Wronkiewicz, 1990;Condie, 1993; Girty et al., 1994; Cullers, 1995; Bier�lein, 1995; Jahn and Condie, 1995; Panahi and Young,

2 The modules are calculated using data on bulk chemical analy�ses, while the above�mentioned indices are calculated usingmolecular quantities of corresponding oxides.

MASLOV et al.

1997; Bhat and Ghosh, 2000). Such an approach isbased on the idea that acid igneous rocks (granites andgranodiorites) are characterized by one to two ordersof magnitude higher values of Th/Sc, La/Sc, La/Co,Th/Co, Th/Cr, and V/Ni ratios as compared withmafic rocks (Interpretatsiya …, 2001); in contrast,mafic rocks are marked by one to two orders of magni�tude higher values of Cr/Zr, Cr/V, and some otherindicator ratios. Application of these ratios also allowsone to reconstruct temporal changes in the composi�tion of rocks in paleodrainage areas. This method ismost efficient for studying relatively thick successionsof fine�grained rocks without sandstones, gravel�stones, and conglomerates.

The rock composition in provenances and type ofthe eroded upper continental crust also control to acertain extent diversity of the chondrite�normalizedREE distribution spectra in post�Archean sedimen�tary rocks (McLennan et al., 1990). For example,basic igneous rocks are characterized by low ratios ofthe light and heavy REE (LREE/HREE < 4 or 5) andabsence of distinct Eu anomaly (Eu/Eu* > 0.85–0.90), while acid rocks demonstrate highLREE/HREE values (>8.0) and well�expressed nega�tive (<0.85) Eu anomaly (Taylor and McLennan,1985; McLennan and Taylor, 1991). The LaN/YbN val�ues ≥20 indicate the prevalence of granitoids in pale�odrainage areas (Wronkiewicz and Condie, 1990).According to (Condie, 1993), the Archean crust ischaracterized by the following average values of ratios:LaN/YbN = 15.68, GdN/YbN = 2.04, and Eu/Eu* =0.83. In (Taylor and McLennan, 1995), the sameparameters are 6.76, 1.38, and 0.99 for the Archeanupper crust and 11.50, 1.78, and 0.72 for the EarlyProterozoic upper crust (Condie, 1993).

Occurrence of ultramafic rocks in provenancesdecreases notably the Cr/Ni value in the fine�grainedterrigenous rocks (down to 1.4–1.5). The Cr/Ni valueof >2.0 implies substantial transformation of the fineterrigenous ultramafic particulate matter during itstransportation (Garver et al., 1996).

For characterizing redox features of bottom watersin sedimentation basins, Russian scientists usuallyapply the Mo/Mn value (Kholodov and Nedumov,1991; Kholodov and Paul, 1999; Gavrilov et al., 2000;Maslov et al., 2003a; Byakov and Vedernikov, 2007). Itis believed that the Mo/Mn value varies from 0.0n to0.n in basins with hydrogen sulfide contamination andis substantially less than 0.00n in well�aerated basins.Researchers abroad report a wider spectrum of suchindicator ratios: Ni/Co, V/Cr, V/(V + Ni), Re/Mo,Mo/Co, V/Co, and U/Th (Hatch and Leventhal,1992; Jones and Manning, 1994; Rachold and Brum�sack, 2001; Rimmer, 2004; Turgeon and Brumsack,2006; and others). However, their simultaneous appli�cation does not always yield consistent results (Maslovet al., 2003a).

The ratios of B, Ga, and Rb in the fine (<0.001 mm)fraction (see, for example, Degens et al., 1957, 1958;

Walker and Price, 1963; Valiev, 1977) or paired ratiosof some other elements in bulk specimens are usedwith certain reservations for reconstructing paleosa�linity. For example, Yanov (1971) suggested that Al/Ti,V/Zr, and Zr/Cu values in the fine�grained terrige�nous rocks are most informative for reconstructingpaleosalinity: Al/Ti varies from 70 to 120 in continen�tal mudstones and only from 15 to 60 in their marinecounterparts; Zr/Cu in marine and continental mud�stones are 1.0–3.5 and 3.5–8.0, respectively. However,correctness of derived inferences is doubtful.

The (Fe + Mn)/Ti ratio, i.e., titanium module(Strakhov, 1976), is useful for defining products ofunderwater exhalations in sediments. In sediments ofrecent basins, which are definitely lacking hydrother�mal activity, the value of this parameter varies usuallyfrom 7.7 to 17.0. If (Fe + Mn)/Ti > 25, one can assumethe presence of hydrothermal material (Strakhov,1976; Butuzova, 1998). The Boström module, Al/(Al+ Fe + Mn) (Boström, 1973) is another indicator ofsuch processes. In sediments with exhalative compo�nents, the value of this module does not exceed 0.4.Recently, some other geochemical indicators have alsobeen proposed for detecting products of underwaterexhalations in sediments: for example, the Zr/Hf ratio(Strekopytov et al., 1995), which is ~33–35 in ordi�nary terrigenous rocks and exceeds 50 in varieties withhydrothermal admixture material; HTSIX index(Peter, 2003); and others.

MATERIALS AND METHODS

Our work is based on the examination of more than50 specimens of fine�grained aluminosiliciclasticrocks from the main Riphean lithostratigraphic subdi�visions in the central and western parts of the Kama–Belaya aulacogen (parametric and exploration bore�holes Kabakovo 62, Severo�Kashkul 1, Kipchak 1,Shkapovo 740, Menzelino�Aktanysh 203 and 20005,Sulli 20007, Arlan 7000) (Fig. 1). The specimens werecollected by L.D. Ozhiganova and M.V. Isherskaya(Ufa) in the 1960s–1990s. Based on comparison ofstratigraphic positions of 34 specimens in boreholesMenzelino�Aktanysh 203, Sulli 20007, Arlan 7000,Kabakovo 62, Severo�Kashkul 1, and Shkapovo 740,we compiles the summary section (Table 1), whichmade it possible to analyze upsection variations ingeochemical features of the fine�grained terrigenousrocks through the Riphean section of the Kama–Belaya aulacogen.

The available specimens of silty mudstones andshales were examined under the microscope and ana�lyzed by the X�ray phase (T.Ya. Gulyaeva, analyst) andthermal (V.G. Petrishcheva, analyst) methods. TheX�ray phase analysis of representative specimens of thefine�grained terrigenous rocks from the Riphean sec�tion of the Kama–Belaya aulacogen was performedwith a DRON�3 X�ray diffractometer (voltage 30 kV,current 30 mA, monochrome Cu radiation, scanning

rate 1 degree/min). Diffractograms were recorded inthe 4°–70° region with a computer attached to the dif�fractometer. The specimens were examined in threestates (initial, oriented, and ignited during 1 h at600°С). Thermal study of the specimens was con�ducted with a DTA/TG derivatograph (Perkin Elmer).Weights of 80–100 mg were used for the study. Theheating rate was 20 degree/min and the temperaturerange was 20–1090°С. Inert matter was represented byaluminum oxide; furnace atmosphere, by air. Weightloss and DTA temperature peak were measured accu�rate to ±0.1% and ± 3°С, respectively.

Concentrations of major and trace elements in thefine�grained terrigenous rocks were determined in theLaboratory of Physicochemical Investigation Meth�ods, Institute of Geology, Yekaterinburg (N.P. Gor�bunova, G.M. Yatluk, V.P. Vlasov, L.A. Tatarinova,G.S. Neupokoeva, E.S. Shagalov, and I.I. Neustroeva,analysts) using a CPM�18 X�ray spectrometer andELAN9000 mass spectrometer (ICP�MS method),respectively.

COMPOSITIONS AND BASIC FEATURES OF THE FINE�GRANED TERRIGENOUS

Shales and silty mudstones from the Prikamsk For�mation are characterized by fine flaky or pelitomor�phic–flaky textures. Based on micropetrographicstudies, the rocks are mainly hydromicaceous (lesscommonly, kaolinite–hydromicaceous) sedimentswith high contents of iron hydroxides and oxides.Some interbeds contain diagenetic pyrite (Masagutov,2002). Silty mudstones and shales in the terrigenousand carbonate–terrigenous beds of the Kaltasy For�mation have the hydromicaceous or chlorite–hydro�micaceous composition. Fine�grained terrigenousrocks from the Nadezhdino Formation are commonlyrepresented by fine flaky sericite–hydromicaceousaggregates with finely dispersed hematite. Silty mud�stones and shales of the Tukaevo Formation are seric�ite–hydromicaceous, hydromica–sericitic or ferrugi�nous–hydromicaceous rocks with pelitomorphic–fine flaky textures (Ivanova et al., 1969; Lagutenkovaand Chepikova, 1982). The Aberda Horizon of theOl’khovka Formation is dominated by hydromica�ceous and sericite–hydromicaceous silty mudstoneswith the fine flaky–fibrous texture and significantadmixture of the finely dispersed carbonaceous mate�rial. In the middle and upper parts of the Ol’khovkaFormation, the fine�grained terrigenous rocks aredominated by hydromicaceous silty mudstones withthe pelitomorphic–fine flaky texture and admixture ofsilty quartz and feldspar grains. In some layers, theycontain a substantial amount of finely dispersedhematite and fine�crystalline dolomite. The Usinskand Priyutovo formations are mostly composed ofhydromicaceous, sericite–hydromicaceous, andhydromicaceous–smectitic silty mudstones. They are

Table 1. Stratigraphic position of some analyzed specimens inthe Riphean summary section of the Kama–Belaya aulacogen

Borehole Sample no.

Sampling interval, m

Distance from the Riphean base, m

Prikamsk Formation

Menzelino�Aktanysh 203

PB�27 3305.9–3313 509

PB�23 3305.9–3313 512

PB�26 3257–3264.7 556

PB�21 3249–3257 697

PB�25 3048–3056.5 767

Sulli 20007 PB�18 3181–3190 1597

PB�47 3176–3180 1604

PB�16 3170–3173 1610

PB�22 3138–3145 1641

PB�17 3138–3145 1644

PB�51 3070–3075 1710

Kaltasy Formation

Arlan 7000 PB�34 2554–2559 2686

PB�36 2551–2554 2689

PB�38 2551–2554 2692

PB�35 2448.8–2453.6 2793

Nadezhdino Formation

Kabakovo 62 PB�1 5469–5471 5455

PB�42 5453–5454 5471

Tukaevo Formation

Kabakovo 62 PB�39 5353–5354 5602

PB�40 5237–5239 5717

PB�3 5237–5239 5719

PB�14 4980–4981 5976

Ol’khovka Formation

Severo�Kush�kul 1

PB�29 3315–3319.5 6164

PB�11 3307–3315 6173

PB�30 3145–3148 6336

PB�6 2980–2986 6499

PB�31 2858–2864 6622

Usinsk Formation

Sulli 20007 PB�19 2785–2792 6847

PB�41 2785–2792 6850

PB�20 2785–2792 6852

PB�52 2782–2787 6854

Priyutovo Formation

Shkapovo 740 PB�7 3582.8–3585.2 6895

PB�10 3575–3579 6966

PB�9 3564–3565 6979

PB�32 3511.6–3512.6 7031

MASLOV et al.

characterized by irregular pigmentation by ironoxides, admixture of silty quartz and feldspar grains(5–15%), and presence of thin clayey–bituminousinterbeds and lenses in some places (Masagutov,2002). Study of silty mudstones under the microscopeshows that they are characterized by fine flaky and pel�itomorphic–fine flaky textures.

Based on the X�ray phase analysis, the examinedspecimens contain muscovite, hydromica (mainreflections 10.0, 4.46, 3.32, and 2.56 Å), and Fe–Mg�chlorite (14.1, 7.1, 4.7, and 3.5 Å). Determination ofmica polytypes is hampered by the interference ofmica, feldspar, and chlorite reflections and by lowintensity and fuzziness of peaks due to fine dispersionof micas. The significant width of refection 10 Å indi�cates the presence of hydromica and muscovite mix�ture. Detrital minerals in shales and silty mudstonesare usually represented by quartz (4.26, 3.34, and2.46 Å), potassic feldspar (4.21, 3.31, 3.28, and3.25 Å), and plagioclase (4.03, 3.78, and 3.20 Å). Sub�ordinate minerals are calcite (3.03, 2.28, and 2.09 Å),dolomite (2.88, 2.19, and 1.78 Å), magnesite (2.74,2.10, and 1.70 Å), hematite (2.70, 2.52, and 1.70 Å),pyrite (2.70, 2.43, and 1.63 Å), and amphibole (8.4,3.1, and 2.7 Å).

According to the thermal studies, Riphean fine�grained terrigenous rocks of the Kama–Belaya aula�cogen contain variable proportions of hydromica,muscovite, quartz, chlorite, and dolomite. In somespecimens, calcite, magnesite, pyrite, and organicmatter were observed. Table 2 presents quantitativeproportions of these minerals revealed by the X�ray

phase analysis (it was accepted that hydromicas con�tain 3.5% of hydroxyl water). Quartz was determinedusing DTA cooling curves with an exopeak corre�sponding to β�α transition. Its quantity was calculatedusing the enthalpy value (for 100% quartz, δН =10.35 J/g) with an accuracy of ±1%.

Analysis of the XRP and DTA data with accountfor the chemical composition of examined rocksrevealed that their clay minerals are mostly repre�sented by hydromica, fine flaky muscovite (endopeakat 700°С), and muscovite variety with endopeak at900–950°С, which are responsible for the above�men�tioned wide 10 Å reflection in diffractograms (speci�mens PB�7, PB�23, and PB�28). The total content ofclay minerals (muscovite, hydromica, and chlorite)usually exceeds 50–60%.

As a whole, fine�grained terrigenous rocks fromdifferent Riphean stratigraphic units of the Kama–Belaya aulacogen are characterized by notable com�positional similarity and only insignificant differencesin proportions of clay minerals. For example, hydrom�ica prevails over muscovite in the Lower Ripheanshales and silty mudstones. The low�carbonaceousshales from this stratigraphic level are marked by insig�nificant admixture of pyrite and organic matter, as wellas the elevated content of fine�gained potassic feldsparand plagioclase. In the Middle Riphean shales, thehydromica content amounts to 40–60% and all speci�mens contain hematite. The Upper Riphean shalesdemonstrate higher hydromica and muscovite, lowermuscovite, and variable dolomite contents but insig�nificant admixture of organic matter and hematite.

Table 2. Mineral composition of Riphean fine�grained terrigenous rocks from the Kama–Belaya aulacogen based on the X�rayphase and thermal study (wt %)

Erathem Forma�tion

Sample no. Hym Mi Chl Sm Qu Pl K�fs Cc Dm Mgz Hm Py Org Amf

Lower Riphean

Prikamsk PB�15 55 5 10 – 10 2–3 10 – – – – 7 – –

PB�17 30 – 10 – 20 1 40 – – – – – 0.1 –

PB�23 35 10 10 – 20 10 15 – – – – – – –

Kaltasy PB�34 40 – 10 – 15 10 25 – – – – – – –

PB�35 55 – 10 – 10 10 15 – – – – – 0.1 –

Nadezh�dino

PB�53 35 – 10 – 15 tr 20 – 7 – 10 – – –

PB�42 – 25 10 – 5 tr 30 – – 25 – 5–7 0.2 –

Middle Riphean

Tukaevo PB�14 60 10 7 – 10 2 10 – – – – 5 0.2 –

PB�39 50 10 10 – 5 tr 20 – – – 5–7 – 0.1 –

Ol’khov�ka

PB�5 40 10 7 – 3 2 20 – 12 – 7 – – –

PB�28 50 10 tr – 5 2 20 2 – – 10 – – –

Upper Riphean

Usinsk PB�20 50 5 10 – 5 2 10 – 11 – 7 – 0.2 –

Priyutovo PB�7 30 35 – 5 5 2 10 – – – 7 – 0.2 5

PB�32 25 10 7 – 15 tr 25 – 12 – 7 – 0.1 –

Note: (Hym) hydromica; (Mi) Muscovite; (Chl) chlorite; (Sm) smectite; (Qu) Quartz; (Pl) plagioclase; (Kfs) potassic feldspar; (Cc) calcite;(Dm) dolomite; (Mag) magnesite; (Hm) hematite; (Py) pyrite; (Org) organic matter; (Amp) amphibole; (TR) traces; (–) not detected.

Table 3 presents the median contents3 of petro�

genic oxides for the whole examined selection ofshales and silty mudstones. Analysis of these datashows that the chemical compositions of Riphean ter�rigenous rocks of the Kama–Belaya aulacogen aremost similar to those of hydromicaceous clays. Themedian SiO2, Al2O3, and TiO2 contents for the selec�tion of 53 specimens are 58.45 ± 4.00, 18.29 ± 2.14, 0.63 ±0.09 wt %, respectively. At the same time, like mostother Upper Precambrian fine�gained detrital rocks(Yudovich and Ketris, 200), the selection under con�sideration is characterized by insignificant mediancontents of potassium oxide (7.77 ± 1.70 wt %). Themaximal (60.83 ± 2.29 wt %) and minimal (54.64 ±2.22 wt %) median SiO2 contents are typical of shalesand silty mudstones from the Prikamsk Formation andanalogous rocks of the Upper Riphean Usinsk Forma�tion, respectively. The maximal median Al2O3 content(18.93 ± 1.64 wt %) is established for shales and siltymudstones of the Middle Riphean Tukaevo Forma�

3 As in our previous works, when analyzing limited analyticalselections, we use median values of contents and ratios of differ�ent oxides and elements, because this statistical parameterallows the generalized assessment of selections with unknowndistribution patterns (Rock et al., 1987)

tion, while its minimal value (16.03 ± 2.31 wt %) isobserved in silty mudstones from the Upper RipheanPriyutovo Formation. The median К2O content in thefine�grained detrital rocks increases upward the Riph�ean section from 5.62 ± 1.90 in the Prikamsk Forma�tion to 9.16 ±1.52 wt % in the Usinsk Formation.

Comparison of median contents of petrogenicoxides in the fine�grained terrigenous rocks from dif�ferent levels of the Riphean section in the Kama–Belaya aulacogen and the average post�Archean Aus�tralian Shale, PAAS (Taylor and McLennan, 1985)composition demonstrates an insignificant upwarddecrease in SiO2 and TiO2 contents: from 0.66 × PAASin the Prikamsk Formation to 0.52 × PAAS in thePriyutovo Formation. The behavior of А12O3 is similarto that of TiO2. As compared with PAAS, medianNa2O contents in shales and silty mudstones demon�strate significant variations at different levels, whilemedian K 2O content in the fine�grained terrigenousrocks in all Riphean formations of the Kama–Belayaaulacogen ranges from 1.52 to 2.48 × PAAS, demon�strating a distinct tendency for its upward growth. Themedian MgO and CaO contents are characterized bydifferent behaviors. The MgOmed value in rocks fromall levels is higher than that in PAAS. In the interval

Table 3. Median contents of petrogenic oxides in the fine�grained terrigenous rocks from different Riphean lithostratigraphicsubdivisions in the Kama–Belaya aulacogen (wt %)

SiO2 А12O3 TiO2 Fе2О3tot MgO СаО МnО Na2O К2O P2O5 L.O.I.

Prikamsk Formation

Median 60.83 18.29 0.66 5.89 2.32 0.30 0.04 1.05 5.62 0.10 3.80

SD 2.29 1.42 0.08 1.17 0.41 0.16 0.03 0.25 1.90 0.03 0.89

Kaltasy Formation

Median 59.00 18.85 0.67 6.77 2.71 0.30 0.03 0.70 5.86 0.09 4.60

SD 3.14 0.89 0.03 0.90 0.34 0.00 0.00 0.15 0.80 0.02 0.70

Median 57.04 16.85 0.58 5.07 3.90 0.30 0.15 1.55 7.46 0.16 5.05

SD 6.48 3.63 0.11 5.04 0.95 1.20 0.25 0.56 2.02 0.04 5.50

Tukaevo Formation

Median 55.74 18.93 0.62 7.62 2.59 0.40 0.02 0.70 7.72 0.22 4.05

SD 4.23 1.64 0.04 4.53 0.19 0.38 0.00 0.55 0.40 0.30 0.36

Median 57.22 17.88 0.59 6.66 2.55 0.30 0.03 1.20 8.34 0.12 4.25

SD 3.22 2.35 0.09 1.56 1.00 1.62 0.01 0.53 1.00 0.04 2.07

Usinsk Formation

Median 54.64 18.59 0.67 5.18 4.01 0.54 0.09 0.60 9.16 0.16 4.75

SD 2.22 3.23 0.14 1.27 1.56 1.81 0.09 0.53 1.52 0.02 2.35

Priyutovo Formation

MedianSD

56.25 3.71

16.032.31

0.520.08

4.162.09

4.171.42

2.231.96

0.060.01

0.750.19

8.480.45

0.130.02

5.852.00

Note: (SD) standard deviation.

MASLOV et al.

from the Prikamsk to Nadezhdino formations, themedian MgO content grows from 1.05 to 1.77 × PAAS,respectively. The MgOmed value is 1.16–1.18 × PAASin shales and silty mudstones of the SerafimovkaGroup and 1.82–1.90 × PAAS in Upper Riphean fine�grained terrigenous rocks. The CaOmed values inLower and Middle Riphean rocks are approximatelyconstant (only 0.23–0.31 × PAAS). TheCaOmed/PAAS value is in shales of the Usinsk Forma�tion 0.42 and increases to 1.72 × PAAS in analogousrocks of the Priyutovo Formation (Fig. 2).

The median HM values vary from 0.35 ± 0.08(Priyutovo Formation) to 0.50 ± 0.09 (Tukaevo For�mation). With respect to this parameter, Ripheanclayey rocks of the Kama–Belaya aulacogen belong tonormal and supersiallites (Yudovich and Ketris, 2000).Median values of the titanium module, TM =ТiO2/Al2O3 in the fine�grained terrigenous rocks fromdifferent Riphean formations are virtually identicaland range from 0.033 to 0.036. Median values of theiron module, IM = (Fe2O3 + FeO + MnO)/(TiO2 +Al2O3) vary from 0.33 to 0.35 in the Lower Ripheanshales and silty mudstones, slightly increases (~0.38)in similar Middle Riphean rocks, decreases upwardthe Abdula Group section (IMus = 0.36, IMprt = 0.27).Median values of the total alkalinity module, SPM =(Nа2О + К2О)/Al2O3 show a notable variation and

upsection increase in the Riphean sequence of theKama–Belaya aulacogen (SPMus = 0.36, SPMnd =0.53, SPMtk = 0.44).

In the Herron’s diagram log(SiO2/Al2O3)–log(Fetot/K2O) (Herron, 1988), data points of theexamined rocks are localized compactly in the field ofshales and only some of them fall into the wacke field(Fig. 3a), indicating that the available database repre�sents precisely the fine�grained detrital rocks and thesubsequently analyzed features of its individual speci�mens correctly characterize typical regularities in suchrocks.

In the SPM–IM classification diagram (Yudovichand Ketris, 2000), data points of the Riphean clayeyrocks from the Kama–Belaya aulacogen are mainlylocalized in fields V and VI corresponding to the chlo�rite–smectite–hydromicaceous and hydromicaceousclays, respectively, with a significant admixture of dis�persed feldspar (Fig. 3b). Noteworthy is the fact thatdata points of the fine�grained detrital rocks from thePrikamsk Formation form in this diagram two clustersthat differ from each other in the SPM values. Thecluster with low SPM values (0.28–0.41, field V)includes rocks of the Norkino Subformation (Prika�msk Formation) recovered by Borehole Menzelino�Aktanysh 203. The cluster with high SPM values(0.54–0.66) is represented by rocks of the MinaevoSubformation (Prikamsk Formation) recovered byBorehole Sulli 20007. This feature likely reflects theinvolvement of successively less mature sedimentsduring the formation of the Prikamsk Formation intoerosion, i. e., clastic material successively less alteredby weathering in paleodrainage areas. Field V of thediagram also includes data points of clayey rocks fromthe Arlan Subformation (Kaltasy Formation), indi�rectly suggesting a new stage in intensification ofweathering in provenances in the middle (or theentire) Kaltasy time. This assumption is also con�firmed by relatively high CIA values in the clayey rocksof lithostratigraphic subdivisions under consideration

In the ТiO2–ТМ diagram (Yudovich and Ketris,2000), most data points available for Riphean fine�grained detrital rocks of the Kama–Belaya aulacogenare localized in the overlapping fields of substantiallyhydromicaceous and smectitic clays (Fig. 3c). Somedata points, which characterize shales and silty mud�stones from the Nadezhdino, Usinsk, and Ol’khovkaformations, are concentrated in the field of mainlysmectitic clays.

In the K/Al–Mg/Al diagram (Turgeon and Brum�sack, 2006), most data points of silty mudstones andshales are localized in the typical field of substantiallyillitic (hydromicaceous) sediments with variableadmixture of potassic feldspar (Fig. 3d). Judging fromratios of the above�mentioned parameters, some spec�imens of fine�grained terrigenous rocks from theNadezhdino, Ol’khovka, Usinsk, and Priyutovo for�mations may be considered as mostly chlorite–hydro�micaceous sediments. At the same time, some shales

0.1prk klt nd tk ol us prt

CaONa2O

Fig. 2. Correlation of median contents of major petrogenicoxides in the fine�grained terrigenous rocks from differentRiphean lithostratigraphic levels in the Kama–Belaya aul�acogen vs. their concentrations in PAAS. Formations:(prk) Prikamsk, (klt) Kaltasy, (nd) Nadezhdino,(kb) Kabakovo, (tk) Tukaevo, (ol) Ol’khovka, (us) Usinsk,(prt) Priyutovo.

specimens from the Prikamsk and Usinsk formationscontain a variable admixture of kaolinite.

Table 4 presents median contents of trace elementsfor all the examined specimens of Riphean shales andsilty mudstones from the Kama–Belaya aulacogen.

Large Ion Lithophile Elements (Rb, Cs, Ba, Sr, Th,and U)

Almost all elements of this group, except Th, U,and in one case Ba (Ol’khovka Formation), are nota�bly higher in the fine�grained terrigenous rocks ascompared with their concentrations in the PAAS(Fig. 4). The LILE distribution patterns are similar atmost stratigraphic levels, although one can also seesome differences. For example, silty mudstones fromthe Tukaevo and Nadezhdino formations differ mark�edly from each other in the Ba content. Except for theKaltasy level, the PAAS�normalized Cs content in thefine�grained rocks is substantially lower as comparedwith Ba.

High�Field Strength Elements (Zr, Nb, Hf, and Y)

Contents of almost all elements from this group areoften sufficiently similar but slightly lower than thosein the PAAS. Maximal (almost an order of magnitude)variations are typical of Y in shales and silty mudstonesfrom the Prikamsk and Ol’khovka formations. In thefine�grained terrigenous rocks of the Prikamsk, Kal�tasy, Usinsk, and Priyutovo levels, the Hf contents arerelatively close to those in the PAAS.

Transitional Metals Group (C, Co, Ni, V, Sc, and Cu)

Contents of elements from this group in most of theexamined specimens (i.e., almost at all stratigraphiclevels of the Riphean section in the Kama–Belaya aul�acogen) are slightly lower than in the PAAS. Maximalvariations are typical of Cu mostly in the Lower Riph�ean shales and silty mudstones. The Middle andUpper Riphean fine�grained terrigenous rocks arecharacterized by a notable Cu deficit (0.09–0.65 ×PAAS): only in one silty mudstone sample from thePriyutovo Formation, the Cu content is almost equalto that in PAAS.

–0.5

–1.0

Fe�shales Fe�sandstones

SublitharenitesShales

Wackes

Arkoses Subarkoses

1.5 2.0log(SiO2/Ai2O3)

0 0.5 1.0

0.010 0.2 0.4 0.6 0.8

0 0.5 1.0 1.5 2.0

TiO2, %

0 0.8 1.0K/Al

Chlorite

Kaolinite

IlliteIllite + K�feldspar

0.60.40.2

Fig. 3. Position of data points of Riphean shales and mud�stones from the Kama–Belaya aulacogen in correlationdiagrams: (a) log(SiO2/Al2O3)–log(Fe2O3tot/K2O) (Her�ron, 1998), (b) SPM–IM, (c) TiO2–TM (Yudovich andKetris, 2000), and (d) K/Al–Mg/Al (Turgeon and Brum�sack, 2006). Fields in diagram SPM–IM (clays): (I)mainly kaolinitic, (II) mainly smectitic with admixture ofkaolinite and hydromica, (III) mainly chloritic withadmixture of Fe�hydromicas, (IV) chlorite–hydromica�ceous, (V) chlorite–smectite–hydromicaceous, (VI)hydromicaceous with significant admixture of dispersedfeldspars. Fields in diagram TiO2–TM (clays): (1) kaoli�nitic, (1a) low�module kaolinitic representing products ofthe catagenetic transformation of smectite or kaolinitesubstrate, (2) substantially hydromicaceous, (3) substan�tially smectitic. K/Al and Mg/Al values for kaolinite, illite,and chlorite are calculated after (Braunlow, 1979). (1–7)Formations: (1) Prikamsk, (2) Kaltasy, (3) Nadezhdino,(4) Tukaevo, (5) Ol’khovka, (6) Usinsk, (7) Priyutovo.

MASLOV et al.

Table 4. Median contents (ppm) of trace elements in the fine�grained terrigenous rocks from different Riphean lithostratigraph�ic subdivisions in the Kama–Belaya aulacogen

t Formations

Prikamsk Kaltasy Nadezhdino Tukaevo Ol’khovka Usinsk Priyutovo

Median SD Median SD Median SD Median SD Median SD Median SD Median SD

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Li 20.17 11.96 64.07 5.26 31.00 9.45 15.44 7.13 37.20 30.12 32.77 4.34 38.66 15.88Be 2.03 0.89 3.79 0.78 2.33 0.76 2.35 1.36 2.34 1.19 3.89 2.66 1.80 0.57Na 1579.35 1036.08 5268.32 1194.97 1041.69 1138.90 949.97 294.19 935.93 281.21 1084.69 401.82 1266.11 218.75Sc 9.61 3.49 12.47 1.16 14.00 3.55 10.50 4.25 12.40 5.12 13.45 3.21 12.37 5.08Ti 3125.38 641.65 3842.63 198.98 2702.32 627.86 3187.74 1151.31 2880.47 1043.97 3666.29 1269.52 2592.38 690.40V 85.60 24.65 106.61 16.68 81.44 18.54 90.96 28.33 82.33 31.48 61.79 18.53 68.90 21.36Cr 76.78 26.41 105.90 5.20 107.54 28.27 103.57 22.84 88.30 20.20 84.88 10.07 91.39 26.96Mn 163.60 211.94 172.11 21.96 932.50 1317.44 75.60 23.37 144.52 161.04 508.83 464.02 366.27 135.57Co 18.37 4.19 16.96 1.50 19.70 3.34 17.59 9.58 16.06 8.59 21.42 3.84 15.73 7.23Ni 37.89 7.15 31.48 2.47 43.86 8.84 43.96 14.48 42.82 19.35 57.38 20.35 33.47 18.21Cu 15.46 46.04 30.12 22.71 23.69 37.70 8.10 3.08 13.20 7.76 21.30 10.17 15.77 18.04Zn 42.07 7.98 65.91 8.00 48.51 34.73 27.04 10.47 40.33 14.02 88.84 20.61 52.22 17.58Ga 22.64 3.76 26.86 3.19 20.92 6.18 24.18 7.44 20.55 9.15 28.67 10.88 21.95 7.93Ge 1.64 0.57 3.37 0.42 1.56 0.25 1.87 0.53 2.38 0.54 1.93 0.14 1.43 0.39Rb 74.72 25.33 82.43 21.16 93.24 11.53 83.82 19.31 85.71 29.04 108.15 14.37 102.52 31.01Sr 48.86 20.53 58.34 23.34 44.34 7.43 67.11 14.51 113.36 59.99 65.06 25.36 112.01 30.78Y 11.65 4.99 12.42 5.36 20.14 3.99 20.07 4.31 16.28 7.35 22.41 2.57 19.72 3.93Zr 146.68 27.95 125.01 28.31 98.78 34.27 98.82 26.07 98.53 39.36 161.00 42.81 187.38 51.80Nb 13.41 1.92 14.87 0.97 11.66 3.28 12.71 3.62 12.54 6.35 17.87 3.78 11.99 3.52Mo 0.26 0.31 0.20 0.01 0.78 0.79 1.97 1.11 0.59 0.81 0.24 0.24 0.64 0.46Ag 0.30 0.20 0.25 0.02 0.29 0.08 0.43 0.46 0.22 0.14 0.31 0.04 0.25 0.05Cd 0.01 0.01 0.02 0.00 0.02 0.02 0.02 0.01 0.01 0.00 0.02 0.00 0.02 0.01Sn 2.10 0.37 2.61 0.37 2.00 0.59 2.44 0.63 2.15 0.94 2.60 1.00 1.91 0.65Sb 0.37 0.10 0.57 0.10 0.29 0.09 0.61 0.33 0.48 0.14 0.25 0.14 0.15 0.09Cs 4.66 1.57 9.06 1.01 3.84 0.91 4.63 1.12 5.03 1.43 5.65 1.05 4.30 2.15Âa 243.86 77.76 247.34 30.91 390.67 44.89 248.38 39.51 295.60 407.06 405.92 68.79 428.87 9.82La 21.72 8.49 26.59 7.21 31.96 18.54 28.13 8.34 26.49 9.69 46.21 7.96 22.56 8.12Ce 43.50 15.26 40.00 14.81 69.00 29.23 44.50 9.32 45.00 23.16 102.00 17.73 55.00 22.08Pr 5.70 2.13 5.91 2.29 10.10 4.82 6.95 1.63 7.23 3.26 16.46 3.22 7.42 2.45Nd 20.51 7.71 21.40 8.94 38.70 17.41 27.02 5.09 26.83 11.40 62.76 14.04 26.96 9.11Sm 3.48 1.31 3.65 1.57 6.93 2.50 5.15 1.11 4.13 1.66 8.52 1.46 4.68 1.55Eu 0.64 0.25 0.71 0.28 1.33 0.44 1.01 0.29 0.82 0.30 1.47 0.19 0.98 0.29Gd 2.52 0.91 2.63 1.07 4.72 1.25 3.83 1.44 2.94 1.16 4.61 0.40 3.57 1.08Tb 0.37 0.13 0.39 0.14 0.65 0.15 0.58 0.17 0.42 0.19 0.64 0.07 0.53 0.14Dy 2.32 0.85 2.46 0.86 4.09 0.91 3.81 0.87 2.96 1.30 4.03 0.44 3.41 0.82Ho 0.46 0.17 0.49 0.16 0.80 0.18 0.76 0.14 0.62 0.27 0.79 0.10 0.68 0.16Er 1.35 0.49 1.41 0.45 2.28 0.47 2.07 0.38 1.73 0.78 2.25 0.33 1.98 0.43Tm 0.20 0.07 0.21 0.07 0.34 0.07 0.29 0.05 0.25 0.12 0.33 0.06 0.30 0.06Yb 1.40 0.45 1.44 0.44 2.22 0.49 1.81 0.33 1.59 0.76 2.24 0.46 1.97 0.36Lu 0.22 0.07 0.22 0.07 0.33 0.07 0.26 0.05 0.23 0.12 0.34 0.07 0.30 0.06Hf 4.99 1.05 4.53 0.86 3.37 0.66 3.64 0.95 2.90 1.56 5.72 1.74 6.12 1.64Ta 0.92 0.15 1.13 0.09 0.88 0.25 0.94 0.28 0.91 0.39 1.21 0.34 0.81 0.25W 1.28 0.23 1.58 0.18 1.08 0.26 1.47 0.12 1.30 0.52 1.26 0.19 0.76 0.29Tl 0.71 0.11 0.87 0.10 0.71 0.17 0.66 0.20 0.59 0.26 0.77 0.29 0.64 0.21Pb 8.43 2.70 8.53 0.51 13.51 5.57 12.37 5.80 8.16 3.69 8.89 1.80 12.28 5.46Bi 0.19 0.42 0.22 0.04 0.14 0.07 0.35 1.25 0.17 0.27 0.14 0.05 0.13 0.07Th 9.50 3.31 11.12 2.32 12.01 3.38 8.94 3.17 8.25 4.52 12.44 2.90 13.82 4.52U 3.70 0.75 2.97 0.20 2.80 0.67 4.30 0.81 2.71 1.47 3.35 0.37 3.62 2.61

Cs Ba Rb Sr Th U Zr Nb Y Hf Cr Co Ni V Sc Cu La Sm GdYb Lu

Fig. 4. The PAAS�normalized contents of large ion lithophile and high�field strength elements, transitional metals, and someREEs in the fine�grained terrigenous rocks from different Riphean lithostratigraphic subdivisions in the Kama–Belaya aulaco�gen. (a–g) Formations: (a) Prikamsk, (b) Kaltasy, (c) Nadezhdino, (d) Tukaevo, (e) Ol’khovka, (f) Usinsk, (g) Priyutovo.

MASLOV et al.

Rare Earth Elements (La, Sm, Gd, Yb, and Lu)

In most of the examined specimens, Gd, Yb, andLu concentrations are slightly lower as compared withthe PAAS. Variations in the ratio of La and Sm in theexamined rocks and PAAS are 0.20–1.51 and 0.23–1.68, respectively. Only in one sample (Lower RipheanNadezhdino Formation), the La content is notablylower as compared with the PAAS.

MAIN DEPOSITIONAL FEATURES OF THE SEDIMENTARY SEQUENCE IN

THE KAMA–BELAYA AULACOGEN

The methods and approaches used in this studymade it possible to obtain new data and specify previ�ous data on general features of the fine�gained alumi�nosiliciclastic material that was delivered to theKama–Belaya aulacogen during the Riphean, itsmaturity degree, and, consequently, paleoclimaticconditions in paleodrainage areas, rock compositionin provenances and its successive changes, and redoxsettings in bottom waters of different age basins. Thesedata were also used for calculating several parametersindicating the presence or lack of exhalative compo�

nents among the fine�grained aluminosiliciclasticsand for the preliminary estimation of paleosalinity inpast basins.

General Features of the Fine�Grained Aluminosiliciclastic Material

The median K2O/Al2O3 value, which can be con�sidered typical for the composition of fine�grainedaluminosiliciclastic material, in the whole examinedselection of Riphean terrigenous rocks of the Kama–Belaya aulacogen ranges from 0.25 to 0.61 (average0.46 ± 0.10 ). This fact suggests several inferences.First, the examined rocks contain a substantialamount of finely dispersed feldspars, indicating a sup�pressed role of chemical weathering in paleodrainageareas and predominance of arid�type climate. It isnoteworthy that minimal K2O/Al2O3 values areobserved in silty mudstones and shales from the lowerpart of the section (Fig. 5). Thus, it can be assumedthat climate aridization increased with time. Second,the examined components are mostly petrogenic, i.e.,virtually unaltered by recycling processes.

Paleoclimate

In all the analyzed specimens of silty–clayey rocksfrom the Riphean section of the Kama–Belaya aula�cogen, the median HM value averages 0.40 ± 0.08.This range is typical of shales and silty mudstones fromthe Lower Riphean Prikamsk and Kaltasy formations(Fig. 6a). In the fine�grained terrigenous rocks of theNadezhdino Formation, the HM value varies from0.44 to 0.68 (the maximal value for the whole selec�tion). The Tukaevo–Priyutovo formation intervaldemonstrates gradual decrease in the HM value andthe minimal value (0.31) is recorded in one of the siltymudstone specimens from the Priyutovo Formation.Thus, the HM value does not show any notable varia�tions in the lower part of the Riphean section andexhibits a tendency for decrease in the upper part(consequently, decrease in maturity degree of the fine�grained terrigenous material delivered to the basin).

The distribution of CIA values in individual shaleand silty mudstone specimens shows slight increaseupward the section (Fig. 6b). Maximal median CIAvalues are typical of the fine�grained detrital rocks ofthe Lower Riphean Prikamsk Formation (68 ± 6) andArlan Subformation of the Kaltasy Formation(70 ± 1), while its minimal values are recorded for siltymudstones of the Upper Riphean Priyutovo Forma�tion (53 ± 9). Thus, the climate in paleodrainage areasduring the initial Prikamsk time and Arlan age of theEarly Riphean was presumably close to the semihu�mid/semiarid one. Shales and silty mudstones of theNadezhdino, Tukaevo, Ol’khovka, and Usinsk forma�tions are characterized by median CIA values rangingfrom 59 ± 6 to 65 ± 5, suggesting relatively low alter�ation degree of primary aluminosiliciclastic material

00.2 0.4 0.6 0.8

K2O/Al2O3

Fig. 5. Variations of K2O/Al2O3 values in the fine�grainedterrigenous rocks of the Riphean summary section of theKama–Belaya aulacogen. See Fig. 3 for legend.

in its mobilization areas and the prevalence of arid orsemiarid climate in paleodrainage basins.

The notable immaturity of fine�gained materialtransported from paleodrainage areas is also evidentfrom high ICV values (0.93–1.0) through the entireRiphean summary section of the Kama–Belaya aula�cogen (Fig. 6c).

Composition of Rocks in Paleodrainage Areas

The position of data points obtained for Ripheanfine�grained terrigenous rocks of the Kama–Belayaaulacogen in diagrams Ni–Cr, GdN/YbN–Eu/Eu*,and La/Sm–Sc/Th (Figs. 7a–7c) demonstrates nota�ble similarity between compositions of examined rocksand PAAS. In diagrams La/Sc–Th/Co and YbN–LaN/YbN (Figs. 7d, 7e), most data points for siltymudstones and shales are localized near the field ofaverage compositions of Proterozoic tonalite–trondhjemite–granite (TTG) associations. At thesame time, the data points are similar to both ArcheanTTG associations and Archean granitoids (Condie,1993). Thus, the composition of Riphean rocks recon�structed from geochemical features of the fine�grainedterrigenous rocks in paleodrainage areas is well consis�

tent with the mineralogical–petrographic and geolog�ical data.

Proportions of Co, Hf, Cr, and Ce in the fine�grained terrigenous rocks represent a very sensitiveindicator for the presence of erosion products of prim�

itive Archean substrates4 (Maslov, 2007). In the prim�

itive Archean substrates, the Co/Hf value varies from 4to 14 (according to (Condie, 1993), this ratio is 6.9 inaverage Archean cratonic shale), while the Ce/Crvalue does not exceed 0.4. Analysis of Co/Hf andCe/Cr values in silty mudstones and shales from dif�ferent levels of the Riphean section in the Kama–Belaya aulacogen revealed that the role of Archeanaluminosiliciclastic material is high in rocks of thePrikamsk and Kaltasy formations, while the Nadezh�dino and higher stratigraphic levels of the Ripheansuccession are notably dominated by geochemicallymore mature material. It is of interest that, similarly asthe Riphean rocks under consideration, the Vendian

4 The primitive Archean substrates are represented either bybasalts and high�magnesian komatiites, which transfer duringtheir destruction significant quantities of Cr, Ni, and Co intorocks, or by dominant Na�granitoids that show distinct deple�tion in HREE and low negative Eu anomalies or lack the anom�alies.

0.5 1.0 50 75 100CIA

Growth of weathering

HM = 0.40(median)

standard deviation

Values typical of

0 Fine�grained terrigenous

Values typical of

Relatively mature

IVC0 1 2 3

(а) (b) (c)

intensity in paleodrainage areas

sediments deposited

under humid

climate

sediments depositedunder arid climate

rocks with relatively highcontents of nonclayey

silicates

fine�grained terrgenous rocks

Fig. 6. Variations of (a) HM, (b) CIA (b) and (c) ICV values in the fine�grained terrigenous rocks of the Riphean summary sectionof the Kama–Belaya aulacogen. See Fig. 3 for legend.

MASLOV et al.

0.50 1 2 3 4

Ni, ppm

CdN/YbN

La/Sm0 5 10 15

100 1000

AR TTGPR TTG

PR1 bas

AR2 bas

0.10 1.00 10.00

AR TTG

PR TTG

30 5 10 15 20

Fig. 7. Position of data points of silty mudstones and shales from different Riphean lithostratigraphic subdivisions in the Kama–Belaya aulacogen in correlation diagrams: (a) Ni–Cr, (b) GdN/YbN–Eu/Eu* (Taylor and McLennan, 1985), (c) La/Sm–Sc/Th(Dobson et al., 2001), (d) La/SC–Th/Co (Cullers, 2002), and (e) YbM–LaN/YbN (Martin, 1986). (PAAS) average post�ArcheanAustralian shale; (AR sh) Archean shale, after (Taylor and McLennan, 1985); (Ar gr) average Archean granite; (PR gr) averageProterozoic granite; (AR TTG) average composition of Archean tonalite–trondhjemite–granite associations; (PR TTG) averagecomposition of Proterozoic tonalite–trondhjemite–granite associations; (AR2bas) average Late Archean basalt; (PR2bas) aver�age Early Proterozoic basalt, after (Condie, 1993). See Fig. 3 for other symbols.

fine�grained terrigenous rocks of the Shkapovo–Shikhany Depression are also delivered from the TatarArch and characterized by Co/Hf and Ce/Cr valuestypical of clayey rocks in the Serafimovka and Abdulagroups (Maslov et al., 2008).

Based on mineralogical–petrographic data, it istraditionally believed that the fine�gained aluminosi�liciclastic material for Upper Vendian clayey rocks ofthe Shkapovo–Shikhany Depression is mostly derivedfrom the Archean garnet�bearing gneisses (Ivanovaet al., 1969). However, our new data refute these con�cepts and suggest that paleodrainage areas surround�ing the Shkapovo–Shikhany Depression in Late Ven�dian were mainly composed of rock complexes withgeochemical features typical of the most post�Archeanrocks or the Archean crust substantially reworked inthe Early Proterozoic.

Predominance of acid igneous rocks in prove�nances through the entire Riphean is also evident fromlocalization of data points of silty mudstones andshales in the La/Sc–Th/Co diagram (Cullers, 2002)(Fig. 8).

Figure 9 illustrates upsection variations in values ofseveral indicator ratios of trace elements in the Riph�ean summary section of the Kama–Belaya aulacogen.

The observed distribution of Th/Sc values in thefine�grained rocks indicates the dominant erosion of

Archean and Lower Proterozoic TTG associations vir�tually through the entire Riphean. This assumption isconsistent with the above inferences based on posi�tions of data points for silty mudstones and shales indiagrams La/Sc–Th/Co and YbN–LaN/YbN. At thesame time, the Th/Sc values in specimens from theTukaevo and uppermost Ol’khovka formations, whichare slightly lower than those in silty mudstones fromother stratigraphic levels, suggest that the paleodrain�age areas also included mafic rocks. This conclusion isconsistent to some extent with mineralogical–petro�graphic data and is also evident from the analysis ofupsection changes in the Th/Cr, La/Sc, Cr/Zr, andV/Ni values through the Riphean section. The rela�tively low C/Ni values (1.20–1.35) in some silty–clayey rock specimens of the Usinsk and Priyutovoformation also indicate the presence of mafic andultramafic rocks in drainage areas.

Figure 10 shows the chondrite�normalized5 REE

spectra in Riphean fine�grained terrigenous rocks ofthe Kama–Belaya aulacogen. Their main parametersare presented in Table 5. As follows from these data,median LaN/YbN values in shales and silty mudstonesof all formations vary from 7.91 (Priyutovo level) to12.95 (Usinsk level). The median value of this param�eter for the whole selection is 10.29, which indicateserosion of a very mature upper continental crust satu�rated with acid rocks (in PAAS, LaN/YbN = 9.2). TheLaN/YbN values in individual specimens vary from

5.04 to 21.016 Both these values are typical of the Mid�

dle Riphean Ol’khovka stratigraphic level. The firstvalue is close to the LaN/YbN value typical of erosionproducts of basic rocks, whereas the second value isclose to that in rocks of the TTG association. Deple�tion in HREE values (GdN/YbN > 2.0) is observed onlyin a few specimens. The negative Eu anomaly variesfrom 0.57 to 0.93, and its median value for the wholeselection is 0.71 (0.66 in PAAS).

The LaN/YbN value in the fine�grained terrigenousrocks of the Riphean section in the Kama–Belaya aul�acogen is characterized by insignificant variations(Fig. 11a). In the Prikamsk, Kaltasy, and Usinsk for�mations, this parameter varies from 8 or 9 to 16–18.Approximately similar values are also typical of theNadezhdino and Tukaevo formations. At the sametime, silty mudstones and shales of the Ol’khovka andPriyutovo formations exhibit slightly lower values (6–11), suggesting some contribution of erosion productsof basic igneous rocks.

No significant changes in the degree of HREEdepletion are observed upward the Riphean section

5 Chondrite composition is given after (Taylor and McLennan,1985).

6 Here, we use the data available for the whole specimen collec�tion, while the summary section includes only specimens char�acterized by vertical succession.

0.01La/Sc

Field of values

1010.1

Field of values typical

typical of acid rocks

of basic rocks

Fig. 8. Position of data points of the Riphean fine�grainedterrigenous rocks from the Kama–Belaya aulacogen indiagram La/Sc–Th/Co (Cullers, 2002). Fields typical oferosion products of acid and basic igneous rocks are givenafter (Cullers, 2002) with insignificant modifications.See Fig. 3 for legend.

MASLOV et al.

1000 0m

1 2 3 4 5 6 7

Fig. 9. Variations in values of some indicator ratios of trace elements in the fine�grained terrigenous rocks from the Riphean sum�mary section of the Kama–Belaya aulacogen. See Fig. 3 for legend.

(Fig. 11b). The same is also true of the negative Euanomaly (Fig. 11c).

Redox Settings in the Bottom Water Layer

The V/Cr values and absolute Mo contents inRiphean silty mudstones and shales of the Kama–Belaya aulacogen suggest that sediments were likely depos�ited mostly in reducing settings at that time (Fig. 12). TheMo/Mn and V/(V + Ni) data indicate a wider spec�trum of sedimentation settings. For example, almostall fine�grained terrigenous rock specimens from thePrikamsk Formation are characterized by Mo/Mnvalues ranging from 0.001 to 0.01, which points to sed�imentation under oxidizing/reducing transitionalconditions. Three of four silty mudstone specimensfrom the Kaltasy Formation demonstrated Mo/Mnvalues ranging from 0.0011 to 0.0013. The same situa�tion is typical of the fine�grained terrigenous rocks ofthe Priyutovo Formation, although corresponding val�ues are slightly higher (0.0023–0.0028). In contrast,three of four analyzed silty–clayey rocks from theNadezhdino Formation and all four silty mudstonespecimens from the Usinsk Formation are character�ized by values of the stagnation coefficient typical ofsediments deposited in a well�aerated basin. TheMo/Mn value in three of four analyzed specimens offine�grained terrigenous rocks from the Tukaevo For�mation varies from 0.024 to 0.073, implying stagnantconditions in the bottom water layer of the basin. TheMo/Mn value in 14 of 17 analyzed silty mudstonespecimens from the Ol’khovka Formation ranges from0.0013 to 0.0091, suggesting their affiliation to the oxi�dizing/reducing transitional settings (Fig. 13a). At thesame time, the U/Th values (Fig. 13b) typical of Riph�ean fine�grained rocks from the Kama–Belaya aula�cogen indicate that all the examined specimens char�acterize sediments of well�aerated basins.

Paleosalinity

In the Zr/Cu–V/Zr diagram proposed in (Yanov,1971), the field of values typical of both freshwater andmarine fine�grained terrigenous rocks comprisesapproximately half of data points; other data pointsare characterized by Zr/Cu values ranging from 8 to20–27 (Fig. 14), which are substantially higher ascompared with values for typical continental rocks.

At the same time, data on the sulfur isotopic com�position in synsedimentary sulfates (δ34S from 18.6 to~24‰), which are relatively widespread in the LowerRiphean section of the Kama–Belaya aulacogen(Michurin, 2008), exhibit significant similaritybetween composition of water in the Riphean basin inthe eastern East European Platform and the present�day seawater, suggesting that sediments of the KyrpyGroup were accumulated in a basin with normal orslightly elevated salinity.

La Ce Pr NdSmEuGdTb DyHo ErTmYb Lu

Fig. 10. Chondrite�normalized REE distribution spectrain the fine�grained terrigenous rocks from different Riph�ean formations in the Kama–Belaya aulacogen. (PAAS)average post�Archean Australian Shale; (AR sh) Archeanshale, after (Taylor and McLennan, 1985). (a–g) Forma�tions: (a) Prikamsk, (b) Kaltasy, (c) Nadezhdino,(d) Tukaevo, (e) Ol’khovka, (f) Usinsk, (g) Priyutovo.

MASLOV et al.

Exhalative Material

Only two of 34 analyzed specimens of fine�grainedterrigenous rocks show (Fe + Mn)/Ti values exceeding25 (Fig. 15). Along with the lack of specimens withAl/(Al + Fe + Mn) < 0.4, this fact indicates terrige�nous nature of the fine�gained aluminosiliciclasticmaterial in the Riphean summary section of theKama–Belaya aulacogen. This inference is also con�firmed by Zr/Hf values in silty mudstones and shalesranging from 26 to 32 (median 29).

DISCUSSION

As was noted, the high median K2O/Al2O3 value(0.46) obtained for the analyzed selection of siltymudstone and shale specimens from the Riphean sec�tion of the Kama–Belaya aulacogen indicates aninsignificant alteration of rocks in provenances bychemical weathering and negligible recycling of fine�grained aluminosiliciclastic material in these areas. It

is remarkable that Riphean fine�grained terrigenousrocks of the Bashkir anticlinorium are characterizedby the median K2O/Al2O3 value of ~0.29 (Maslovet al., 2005). Since most researchers consider the TatarArch as one of the main sources of detrital material forboth Kama–Belaya aulacogen and the present�daywestern slope of the South Urals, it is reasonable tosuggest that the fine�grained terrigenous material inthe latter region experienced notable maturationbefore its eventual burial.

The upsection K2O/Al2O3 growth in the fine�grained terrigenous rocks through the Riphean sectionof the Kama–Belaya aulacogen is consistent with thesimilarly directed increase in the median CIA value,indicating progressive aridization in drainage areas bythe terminal Riphean. The maximal median CIAvalue (70) is typical of shales and silty mudstones ofthe Lower Riphean Kaltasy level in the Kama–Belayaaulacogen. In the Riphean type section, the mostmature fine�grained aluminosiliciclastic material withthe CIA values ranging from 70 to 76 occurs at higherlevels ranging from the Lower Riphean Bakal Forma�tion to the Middle Riphean Avzyan Formation.

Mineralogical–petrographic data on the composi�tion of Riphean psammites of the Kama–Belaya aula�cogen point to domination of acid igneous and meta�morphic rocks in paleodrainage areas through theentire Riphean. Based on admixture of magnetite andpyroxene grains in the heavy fraction, presence ofmafic and ultramafic rocks is assumed only for theNadezhdino and Usinsk stratigraphic levels (Verkh�nii…, 1995). Our data on chemical features of Ripheanfine�grained terrigenous rocks of the Kama–Belayaaulacogen imply that mafic and ultramafic rocks weresubjected to different degrees of erosion during theaccumulation of sediments in the Tukaevo,Ol’khovka, and Priyutovo time, in addition to theNadezhdino and Usinsk time. Thus, it is reasonable toassume that the composition of rocks in erosion areaswas relatively homogeneous only in the initial andmiddle Early Riphean. Subsequently, the rock compo�sition in provenances became more diverse probablydue to some widening of paleodrainage areas and pro�gressing destruction of the continental crust.

Analysis of some indicator parameters of redoxconditions in bottom waters indicates that sedimenta�tion in the study areas of the Kama–Belaya aulacogenproceeded virtually through the entire Riphean mostlyin oxidizing settings. Similar depositional environ�ments are also typical of the Riphean type section inthe Bashkir anticlinorium (Maslov et al., 2003a).

Unfortunately, the available lithogeochemical dataon Riphean fine�grained terrigenous rocks of theKama–Belaya aulacogen provide no grounds forreconstructing paleosalinity of the Early, Middle, andLate Riphean sedimentation basins. Nevertheless, thedeficit in information on this paleogeographic aspectis covered to a certain extent by data on the sulfur iso�topic composition in synsedimentary sulfates in the

Table 5. Main parameters of chondrite�normalized REE dis�tribution spectra of the fine�grained terrigenous rocks fromdifferent Riphean formations in the Kama–Belaya aulacogen

LREE/HREE LaN/SmN GdN/YbN Eu/Eu*

Prikamsk Formation

MedianSD

9.79 2.73

3.55 1.15

1.44 0.16

0.69 0.05

Kaltasy Formation

MedianSD

12.84 0.98

4.62 0.80

1.48 0.11

0.70 0.01

MedianSD

10.99 3.02

3.90 0.69

1.66 0.16

0.72 0.02

Tukaevo Formation

MedianSD

10.46 1.35

3.62 0.92

1.74 0.78

0.71 0.03

MedianSD

9.83 3.70

3.70 0.83

1.60 0.33

0.69 0.07

Usinsk Formation

MedianSD

12.95 4.03

3.34 0.22

1.53 0.34

0.72 0.02

Priyutovo Formation

MedianSD

7.91 1.91

3.01 0.42

1.46 0.17

0.74 0.03

Lower Riphean Kyrpy Group (Michurin, 2008). It isremarkable that approximately the same situation istypical of the Lower Riphean rocks in the Bashkiranticlinorium. For example, the thorough study of theBurzyan Group sections in the Bakal–Satka miningarea revealed lithological indications of the previousdevelopment of evaporitic sediments in the Lower andMiddle Riphean sections: inclusions of anhydrite,gypsum, and fluorite in dolomites; diverse (locally,sufficiently thick) diagenetic dolomitic collapse brec�cia related to selective replacement of the readily sol�uble evaporitic minerals in the course of low�temper�ature near�surface magnesian metasomatism; widedevelopment of tepee structures in dolomites of theSatka Formation indicating the early diageneticgrowth of sulfates; acute�angled nests of white coarse�grained dolomite in dark gray fine�grained dolomites;and chalcedony–quartz inclusions and acute�angled(sometimes wedge�shaped or spherical�discoid) sedi�ments in peripheral parts of the nests (Krupenin, 2005,2007). The lithological reconstructions are confirmedby the detailed study of evaporitic microtextures underthe scanning electron microscope. The precision studyof fluid inclusions in magnesites and dolomites fromthe Satka and Bakal magnesite ore fields demonstrated

consistency of their molar Cl/Br and Na/Br valueswith those in evaporate brines (Krupenin andProchaska, 2005), while their host limestones arecharacterized by typical normal seawater values ofboth parameters.

Similar as in the type section of the Bashkir anticli�norium, no admixture of exhalative components isdetected in Riphean rocks of the Kama–Belaya aula�cogen by geochemical methods (REE systematicsincluded), despite the riftogenic nature of some sedi�mentary associations in this area assumed in literature(Formirovanie…, 1986; Masagutov, 2002). Conse�quently, it is highly conceivable that crustal permeabil�ity at the East European Platform/present�day SouthUrals junction was relatively low during the entireRiphean.

CONCLUSIONS

The performed studies revealed that fine�grainedaluminosiliciclastic material accumulated in theKama–Belaya aulacogen was characterized by a verylow maturity virtually during the entire Riphean, sug�gesting an insignificant chemical weathering in pale�odrainage areas. The role of recycling processes in the

0LaN/YbN

20 0 2.0 4.0GdN/YbN Eu/Eu*

0.4 0.6 0.8 1.0

(a) (b) (c)

Fig. 11. Variations in the major parameters of chondrite�normalized REE spectra in the fine�grained terrigenous rocks from theRiphean summary section of the Kama–Belaya aulacogen. See Fig. 3 for legend.

MASLOV et al.

formation of fine�grained terrigenous rocks was alsonegligible. In terms of the K2O/Al2O3 value, Ripheanfine�grained terrigenous rocks of the Kama–Belaya

aulacogen differ notably from their counterparts in theeastern Bashkir anticlinorium.

In the Riphean summary section of the Kama–Belaya aulacogen, the K2O/Al2O3 values correlatenegatively with the CIA values, indicating intensifica�tion of aridization in paleodrainage areas by the termi�nal Riphean. This tendency is generally comparablewith CIA changes in the Riphean type section,although there are also some differences. MaximalCIA values are typical of fine�grained terrigenousrocks from the lower part of the Prikamsk Formationand silty mudstones from the Arlan Subformation(Kaltasy Formation), i.e., of lower and middle levels inthe Lower Riphean section of the Kama–Belaya aula�cogen. Rocks from other Riphean levels are character�ized by relatively low values of this paleoclimatic indi�cator. In the Riphean type section of the Bashkir anti�clinorium, the most mature fine�grainedaluminosiliciclastic material is observed in the upper�most Lower Riphean (Bakal Formation) and MiddleRiphean (Mashak and Zigal’ga formations) sedimen�tary successions.

Oxic Dysoxic Suboxic/anoxic

05 10 15

Oxicе Dysoxic Suboxic/anoxi

Fig. 12. Position of data points of Riphean silty mudstonesand shales from the Kama–Belaya aulacogen in correla�tion diagrams: (a) Ni/Co–V/Cr, (b) Ni/Co–V(V + Ni),(c) Ni/Co–Mn, and (d) Ni/Co–Mo/Mn (Turgeon andBrumsack, 2006). Fields of different redox settings areshown after (Kholodov and Nedumov, 1991; Turgeon andBrumsack, 2006). See Fig. 3 for legend.

0Mo/Mn

0.050 0 0.5 1.0U/Th

(a) (b)

Transitional

Euxinic

Transitional

Fig. 13. Variations of (a) Mo/Mn and (b) U/Th values inthe fine�grained terrigenous rocks from the Riphean sum�mary section of the Kama–Belaya aulacogen. Fields ofdifferent redox settings are shown after (Kholodov andNedumov, 1991; Jones and Manning, 1994). See Fig. 3 forlegend.

0 10 20 30Zr/Cu

Range of values

typical of marinesediments

typical of continentalsediments

Fig. 14. Position of data points of silty mudstones and shales from different Riphean formations in the Kama–Belaya aulacogenin diagram Zr/Cu–V/Zr (Yanov, 1971). Fields of Zr/Cu and V/Zr values typical of different paleosalinity settings are shown after(Yanov, 1971). See Fig. 3 for legend.

0(Fe + Mn)/Ti

40 0.4 20 40

(а) (b) (c)

302010Al/(Al + Fe + Mn) Zr/Hf

0.6 0.8

Range of values typical

of sediments with dmixture of exhalative

components

Range of values typicalof sediments with

dmixture of exhalativecomponents

of ordinaryterrigenous sediments

Fig. 15. Variations of (a) titanium and (b) aluminum modules and (c) Zr/Hf values in the fine�grained terrigenous rocks fromdifferent lithostratigraphic subdivisions in the Riphean summary section of the Kama–Belaya aulacogen.Fields of values typical of ordinary terrigenous sediments and sediments with admixture of exhalative components are shown after(Strakhov, 1976; Bostrom, 1973; Strekopytov et al., 1995). See Fig. 3 for legend.

MASLOV et al.

Some indicator ratios of trace elements and REEsystematics in Riphean silty mudstones and shales ofthe Kama–Belaya aulacogen suggest that paleodrain�age areas hosted mafic and ultramafic rocks, in addi�tion to acid igneous and metamorphic varieties. Com�parison of data on the composition of rocks in prove�nances based on the mineralogical–petrographicstudy of sandstones and geochemical features of siltymudstones and shales revealed their significant simi�larity. At the same time, the geochemical informationprovided new insight into the composition of rocks inprovenances for some Riphean (Tukaevo, Ol’khovka,and Priyutovo) levels of the Kama–Belaya aulacogen.The principle inference, which cannot be derived, inour opinion, from mineralogical–petrographic data,is as follows: erosion products of primitive Archeansubstrates made a notable or substantial contributionto the formation of fine�grained terrigenous rocks inthe lower and middle parts of the Kyrpy Group. Inrocks of higher levels of the Riphean megasuccessionin the Kama–Belaya aulacogen, as well as in UpperVendian silty mudstones and shales of the Shpakovo–Shikhany Depression, the contribution of similar sub�strates was likely minimal. Thus, the mineral feedingsystem of the Kama–Belaya aulacogen was subjectedto substantial reorganization approximately at theEarly/Middle Riphean transition (terminal Kaltasy orinitial Tukaevo time).

Analysis of Mo/Mn values and some other indica�tors of redox conditions in bottom waters, which aretypical of Riphean fine�grained terrigenous rocks ofthe Kama–Belaya aulacogen revealed that they usu�ally accumulated in oxidizing settings. Clear develop�ment of stagnant conditions may be assumed only forsome intervals of the Prikamsk, Tukaevo, and initialOl’khovka time (accumulation of the Akberda Hori�zon).

As is evident from lithological and isotopic–geochemical data, salinity in the Early, Middle, andLate Riphean sedimentation basins was likely compa�rable with that in present�day oceanic basins. Theshallowest, probably, closed or semiclosed parts ofthese basins were marked by the development of con�ditions in some periods favorable for the precipitationof evaporitic minerals or pure evaporates.

The lack of exhalative components in the examinedspecimens of fine�grained terrigenous rocks indicatesrelatively low crust permeability at the East EuropeanPlatform/South Urals junction in the entire Riphean.

ACKNOWLEDGMENTS

This study was supported by the integration projectof the Uralian and Siberian Divisions of the RussianAcademy of Sciences (program 6.6 “PrecambrianSedimentary Successions of the Urals and Siberia:Types and Character of Provenances, Long�TermVariations in the Crustal Composition, and Issue ofRecycling”).

REFERENCES

Aksenov, E.M., History of Evolution of the East EuropeanPlatform in Late Paleozoic, DSc (Geol.�Miner.) Disserta�tion, St. Petersburg: Inst. Geol. Geochim. DokembriyaRoss. Akad. Nauk, 1998.

Aksenov, E.M. and Solontsov, A.F., Riphean and Vendian ofthe East Russian Plate, Dokembriiskie vulkanogenno�osa�dochnye kompleksy Urala (Precambrian Volcanogenic Sed�imentary Complexes of the Urals), Sverdlovsk: Ufim.Nauchn. Tsentr Akad. Nauk SSSR, 1986, pp. 117–127.

Aksenov, E.M., Baranov, V.V., Kaveev, I.Kh., and Solontsov, L.F.,New Data on Upper Precambrian of the East Russian Plate,Izv. Akad. Nauk SSSR. Ser. Geol. 1984, no. 7, pp. 144–148.

Aliev, M.M., Morozov, S.T., Postnikova, I.E., et al.,Geologiya i neftegazonosnost' rifeiskikh I vendskikh otlozheniiVolgo�Ural’skoi provintsii (Geology and Petroleum Poten�tial of Riphean and Vendian Rocks in the Volga�UralianProvince), Moscow: Nedra, 1977.

Andreev, Yu.V., Ivanova, T.V., Keller, B.M., et al., UpperProterozoic Stratigraphy of the Eastern Margin of the Rus�sian Plate and Western Slope of the Southern Urals, Izv.Akad. Nauk SSSR, Ser. Geol., 1981, no. 10, pp. 57–68.

Belokon, T.V., Balashova, M.M., and Gorbachev, V.I., Per�spektivy izucheniya neftegazonosnosti verchnedokembriiskichotlozhenii vostoka Russkoi platformy (Prospects of the Studyof Oil and Gas Potential of Upper Precambrian Rocks inthe East Russian Platform), Otech. Geol., 1994, no. 3,pp. 3–10.

Belokon, T.V., Balashova, M.M., Sirotenko, O.I., et al.,Geodynamic Conditions of the Formation and Transfor�mation of Riphean Sequences of the East Russian Platform,in Obshchie voprosy stratigrafii i geologicheskoi istorii rifeyaSevernoi Evrazii (General Problems of the Riphean Stratig�raphy and Geological History of North Eurasia), Yekaterin�burg: Inst. Geol. Geochim. Ural. Otd. Ross. Akad Nauk,1995, pp. 18–19.

Belokon, T.V., Gorbachev, V.I., and Balashova, M.M., Stro�enie i neftegazonosnost’ rifeisko�vendskikh otlozhenii vostokaRusskoi platformy (Structure and Petroleum Potential of theRiphean�Vendian Rocks of the East Russian Platform),Perm: IPK Zvezda, 2001.

Berzin, R., Onchen, O., Knapp, J.H., et al., Orogenic Evo�lution of the Ural Mountains: Results from an IntegratedSeismic Experiment, Science, 1996, vol. 274, pp. 220–221.

Bhat, M.I. and Ghosh, S.K., Geochemistry of the 2.51 GaOld Rampur Pelites, Western Himalayas: Implications forTheir Provenance and Weathering, Precambrian Res., 2001,vol. 108, pp. 1–16.

Bierlein, F.P., Rare�Earth Element Geochemistry Oof Clasticand Chemical Metasedimentary Rocks Associated withHydrothermal Sulfide Mineralization in the Olary Block,South Australia, Chem. Geol., 1995, vol. 122, pp. 77–98.

Bogdanova, S.V., Zemnaya kora Russkoi plity v rannemdokembrii (na primere Volgo�Ural’skogo segmenta) (TheEarth’s Crust in the Russian Plate in Early Precambrianwith the Volga�Ural Segment as Example), Moscow:Nauka, 1986.

Bogdanova, S.V., Bingen, B., Gorbatschev, R., et al., TheEast European Platform (Baltica) before and during theAssembly of Rodinia, Precambrian Res., 2008, vol. 160,pp. 23–45.

Boström, K., The Origin and Fate of FerromanganoanActive Ridge Sediments, Stockholm Contrib. Geol., 1973,vol. 27, no.2, pp. 148–243.

Brownlow, A.H., Geochemistry, Prentice Hall Publ., 1981.Translated under the title Geokhimiya, Moscow: Nedra,1984.

Butuzova, G.Yu., Gidrotermal’no�osadochnoe rudoobrazo�vanie v riftovoi zone Krasnogo morya (Hydrothermal Sedi�mentary Ore Formation in the Red Sea Rift Zone), Mos�cow: GEOS, 1998.

Biakov, A.S. and Vedernikov, I.L., Evidence for Anoxia inDeep Environments of Northeast Asia at the Permian–Tri�assic Transition, Dokl. Akad. Nauk, 2007, vol. 417, no. 5,pp. 654–656 [Dokl. Earth Sci. (Engl. Transl.), 2007,vol. 417A, no. 9, pp. 1325–1327].

Carhonell, R., Perez�Estaun A., Gallart, J., et al., CrustalRoot beneath the Urals: Wide�Angle Seismic Evidence,Science, 1996, vol. 274, pp. 222–224.

Condie, K.C., Chemical Composition and Evolution of theUpper Continental Crust: Contrasting Results from SurfaceSamples and Shales, Chem. Geol., 1993, vol. 104, pp. 1–37.

Condie, K.C., Wronkiewicz, D.A., The Cr/Th Ratio inPrecambrian Pelites from the Kaapvaal Craton as an Indexof Craton Evolution, Earth Planet. Sci. Lett., 1990, vol. 97,pp. 256–267.

Cox, R., Lowe, D.R., Cullers, R.L., The Influence of Sed�iment Recycling and Basement Composition on Evolutionof Mudrock Chemistry in the Southwestern United States,Geochim. Cosmochim. Acta., 1995, vol. 59, pp. 2919–2940.

Cullers R.L., The Control on The Major� and Trace�ElementEvolution of Shales, Siltstones and Sandstones of Ordovicianto Tertiary Age in the Wet Mountains Region, Colorado,U.S.A., Chem. Geol., 19951, vol. 123, pp. 107–131.

Cullers, R.L., Implications of Elemental Concentrationsfor Provenance, Redox Conditions, and MetamorphicStudies of Shales and Limestones near Pueblo, CO, USA,Chem. Geol., 20022, vol. 191, pp. 305–327.

Davis, B.E., Applied Soil Trace Elements, New York: Wiley& Sons, 1980.

Degens, E.T., Williams, E.G., Keith, M.L., EnvironmentalStudies of Carboniferous Sediments. Part I: GeochemicalCriteria for Differentiating Marine from Fresh�WaterShales, Am. Assoc. Petrol. Geol., 1957, vol. 41, no. 11,pp. 2447–2455.

Degens, E.T., Williams, E.G., and Keith, M.L., Environ�mental Studies of Carboniferous Sediments. Part II: Appli�cation of Geochemical Criteria, Am. Assoc. Petrol. Geol.,1958, vol. 42, no. 5, pp. 981–997.

Dobson, D.M., Dickens, G.R., and Rea, D.K., Terrige�nous Sediments on Ceara Rise: A Cenozoic Record ofSouth American Orogeny and Erosion, Palaeogeogr. Palae�oclimat. Palaeoecol., 2001, vol. 165, pp. 215–229.

Echtler, H.P., Stiller, M., Steinhoff, F., et al., PreservedCollision Crustal Structure of the Southern Urals Revealedby Vibroseis Profiling, Science, 1996, vol. 274, pp. 224–226.

Formirovanie zemnoi kory Urala (Formation of the Earth’sCrust ofin the Urals), Moscow: Nauka, 1986.

Frolovich, G.M., Comparison of Precambrian Sections inthe Kama�Belaya Depression, Izv. Akad. Nauk SSSR. Ser.Geol., 1980, no. 4, pp. 75–85.

Garver, J.I, Royce P.R. and Smick T.A. Chromium and Nickelin Shale of the Tacinic Foreland: A Case Study for the Prove�nance of Fine�Grained Sediments with an Ultramafic Source,J. Sedim. Res., 1996, vol. 66, no. 1, pp. 100–106.Gavrilov, Yu.O., Shchepetova, E.V., Baraboshkin, E.Yu.,and Shcherbinina, E.A., The Early Cretaceous AnoxicBasin of the Russian Plate: Sedimentology and Geochem�istry, Litol. Polezn. Iskop., 2002, vol. 37, no. 4, pp. 359–380[Lithol. Miner. Resour. (Engl. Transl.), 2002, vol. 37, no. 4,pp. 310–329].Geochemistry of Sediments and Sedimentary Rocks: Evolu�tionary Considerations to Mineral Deposit�Forming Environ�ments, Lentz, D.R., Ed., Geol. Assoc. Canada, 2003, Geo�Text 4.Girty, G.H., Hanson, A.D., Knaack, C., and Johnson, D.,Provenance Determined by REE, Th, Sc Analyses ofMetasedimentary Rocks, Boyden Cave Roof Pendant,Central Sierra Nevada, California, J. Sedim. Res., 1994,vol. B64, pp. 68–73.Glubinnoe stroenie i geodinamika Yuzhnogo Urala (proektUralseis) (Deep Structure and Geodynamics of the South�ern Urals: Project Uralseis), Tver: GERS, 2001.Gorozhanin, V.M., New Geochronological Data on theUpper Precambrian in Tataria (Borehole 20005 Karachev�skaya), in Stratigrafiya i litologiya verkhnego dokembriya ipaleozoya Yuzhnogo Urala i Priural’ya (Upper Precambrianand Paleozoic Stratigraphy and Lithology in the SouthernUrals and Ural Region), Ufa: Bash. Fil. Akad. Nauk SSSR,1983, pp. 48–51.Harnois, L., The CIW Index: A New Chemical Index of Weath�ering, Sedim. Geol., 1988, vol. 55, no. 3–4, pp. 319–322.Hatch, J.R. and Leventhal, J.S., Relationship betweenInferred Redox Potential of the Depositional Environmentand Geochemistry of the Upper Pennsylvanian (Missou�rian) Stark Shale Member of the Dennis Limestone,Wabaunsee County, Kansas, U.S.A., Chem. Geol., 1992,vol. 99, pp. 65–82.Herron, M.M., Geochemical Classification of TerrigenousSands and Shales from Core or Log Data, J. Sedim. Petrol.,1988, vol. 58, pp. 820–829.Interpretatsiya geokhimicheskikh dannykh (Interpretation ofGeochemical Data), Sklyarov, E.V., Ed., Moscow: IntermetInzhiniring, 2001.Isherskaya, M.V. and Romanov, V.A., K stratigrafii rifeiskikhotlozhenii Zapadnoi Bashkirii (Stratigraphy of RipheanRocks), Ufa: Inst. Geol. Ufim. Nauchn. Tsentra Ross.Akad. Nauk,, 1993.Ivanova, T.V., Some Problems of Early Riphean Sedimen�togenesis in Northwestern Bashkiria, in Stratigrafiya i lito�logiya paleozoya Volgo�Ural’skoi oblasti (Paleozoic Stratig�raphy and Lithology in the Volga�Ural Area), Kazan:Kazan. Fil. Akad. Nauk SSSR, 1970, pp. 7–14.Ivanova, T.V., Andreev, Yu.V., Masagutov, R.Kh., et al.,Tectonic Evolution of the East Russian Plate during theRiphean Stage, in Verkhnii dokembrii Yuzhnogo Urala i vos�toka Russkoi plity (Upper Precambrian of the SouthernUrals and the East Russian Plate), Ufa: Inst. Geol. Ufim.Nauchn. Tsentra Ross. Akad. Nauk, 1993, pp. 85–94.Ivanova, Z.P., Veselovskaya, M.M., Klevtsova, A.A., et al.,Neftegazonosnye i perspektivnye kompleksy tsentral’nykh ivostochnykh oblastei Russkoi platformy (Petroleum Poten�tial and Prospecting Complexes of Central and Eastern

MASLOV et al.

Areas of the Russian Platform), Vol. 1: Preordovician Rocksin Central and Eastern Areas of the Russian Platform),Leningrad: Nedra, 1969.

Jahn, B.�M. and Condie, K.C., Evolution of the KaapvaalCraton as Viewed from Geochemical and Sm�Nd IsotopicAnalyses of Intracratonic Pelites, Geochim. Cosmochim.Acta, 1995, vol. 59, pp. 2239–2258.

Jones, B. and Manning, D.A.C., Comparison of Geochem�ical Indices Used for the Interpretation of PalaeoredoxConditions in Ancient Mudstones, Chem. Geol., 1994,vol. 111, pp. 111–129.

Kazakov, G.A., Knorre K.G., and Strizhov V.P. New Datathe on Age of Lower Formations of the Lower Bavly Groupof the Volga�Ural Area, Geokhimiya, 1967, vol. 5, no. 4,pp. 482–485.

Kholodov, V.K and Nedumov, R.I., Geochemical Criteriaof the Appearance of Hydrosulfuric Contamination inWaters of Ancient Basins, Izv. Akad. Nauk SSSR, Ser. Geol.,1991, no. 12, pp. 74–82.

Kholodov, V.N. and Paul, R.K., Facies and Genesis ofKaratau Phosphorites: Communication 1. The Vendian–Cambrian Paleobasin and Morphometry of Phosphate Pel�lets, Litol. Polezn. Iskop., 1999, vol. 34, no. 4, pp. 350�367[Lithol. Miner. Resour. (Engl. Transl.), 1999, vol. 34, no. 4,pp. 305–321].

Krupenin, M.T., Geological–Geochemical Types and REESystematization in Rocks of the South Urals MagnesiteProvince, Dokl. Akad. Nauk, 2005, vol. 405, no. 2, pp. 243–246[Dokl. Earth Sci. (Engl. Transl.), 2005, vol. 405, no. 8,pp. 1253–1256].

Krupenin, M.T., Diagenetic Breccia in Dolomites of theSatkina Formation of the Lower Riphean: Traces ofEvaporite Basin?, in Ezhegodnik�2006 (Yearbook 2006),Yekaterinburg: Inst. Geol. Geokhim. Ural. Otd. Ross.Akad. Nauk, 2007, pp. 78–84.

Krupenin, M.T. and Prochaska, W., The Evaporite Nature ofFluid Inclusions in Sparry Magnesites of the Satka Type, Dokl.Akad. Nauk, 2005, vol. 403, no. 5, pp. 661�663 [Dokl. EarthSci. (Engl. Transl.), 2005, vol. 403A, no. 6, pp. 838–840].

Lagutenkova, N.S. and Chepikova, I.K., Verkhnedokembri�iskie otlozheniya Volgo�Ural’skoi oblasti i perspektivy ikhneftegazonosnosti (Upper Precambrian Rocks of the Volga�Ural Area and Hydrocarbon Potential), Moscow: Nauka,1982.

Lozin, E.V., Tektonika i neftenosnost' platformennogo Bash�kortostana (Tectonics and Petroleum Potential of Platfor�mal Bashkortostan), Moscow: Vseross. Naucno�Issled.Inst. OENG, 1994, part 1.

Lozin, E.V., Tectonic Evolution and Hydrocarbon Potentialof Riphean and Vendian Rocks of the Southeastern EastEuropean Platform, in Stratigrafiya, paleontologiya i perspe�ktivy neftegazonosnosti rifeiskikh i vendskikh otlozhenii vos�tochnoi chasti Vostochno�Evropeiskoi platformy (Stratigra�phy, Paleotology, and Petroleum Potential of Riphean andVendian Rocks in the Eastern East European Platform),Ufa: Inst. Geol. Ural. Nauchn. Tsentr Ross. Akad Nauk,1999, part 1, pp. 49–54.

Lozin, E.V. and Khasanov, V.Kh., Geodynamic Model ofthe Formation the Folded Urals Based on the Troitskii DSSProfile, in Geologiya, geofizika i poleznye iskopaemye Yuzh�nogo Urala i Priural’ya (Geology, Geophysics, and Mineral

Resources of the Southern Urals), Ufa: Bashkir. Nauchn.Tsentr Ural. Otd. Akad. Nauk SSSR, 1991a, pp. 58–63.Lozin, E.V. and Khasanov, V.Kh., Seismic�Geological Dataon Deep Structure of the Platform Margin and SouthernUrals, in Geologiya, geofizika i poleznye iskopaemye Yuzh�nogo Urala i Priural’ya (Geology, Geophysics, and MineralResources of the Southern Ural and Ural Region), Ufa:Bashkir. Nauchn. Tsentr Ural. Otd. Akad. Nauk SSSR,1991b.Martin, H., Effect of Steeper Archean Geothermal Gradi�ents on Geochemistry of Subduction�Related Magmas,Geology, 1986, vol. 4, pp. 753–756.McLennan, S.M., Rare Earth Elements in SedimentaryRocks: Influence of Provenance and Sedimentary ProcessesGeochemistry and Mineralogy of Rare Earth Elements,Lipin, B.R. and McKay, G.A., Eds., Rev. Miner., 1989,vol. 21, pp. 169–200.McLennan, S.M. and Taylor, S.R., Sedimentary Rocks andCrustal Evolution: Tectonic Setting and Secular Trends,J. Geol., 1991, vol. 99, pp. 1–21.McLennan, S.M., Taylor, S.R., McCulloch, M.T., andMaynard, J.B. Geochemical and Nd�Sr Isotopic Composi�tion of Deep�Sea Turbidites: Crustal Evolution and PlateTectonic Associations, Geochim. Cosmochim. Acta, 1990,vol. 54, pp. 2015–2050.Masagutov, R.Kh., Litologo�stratigraficheskaya kharakteris�tika i paleogeografiya pozdnego dokembriya BashkirskogoPriural’ya (Late Precambrian Lithostratigraphic Charac�teristics and Paleogeography of the Bashkirian UralRegion), Moscow: Nedra, 2002.Maslov, A.V., Early Riphean Volga�Ural SedimentationBasin, Litol. Polezn. Iskop., 1994, vol. 29, no. 5, pp. 99–118.Maslov, A.V., Early Riphean Sedimentation Basin in theEastern East European Platform and Southern Urals,Otech. Geol., 1995, no. 4, pp. 45–52.Maslov, A.V., Riphean Sedimentary Basins on the WesternSlope of the Southern Urals: Facies, Lithofacies Com�plexes, Paleogeography, Features of Evolution, DSc (Geol.�Miner.) Dissertation, Yekaterinburg: Inst. Geol. Geokhim.Ural. Otd. Ross. Akad. Nauk, 1997.Maslov, A.V., Middle Riphean Sedimentary Basin in theJunction Area between the Russian Platform and SouthUrals: Lithology, Facies, Paleogeography, and EvolutionaryTrend, Stratigr. Geol. Korrelyatsiya, 2000, vol. 8, no. 1,pp. 17�34 [Stratigr. Geol. Correlation (Engl. Transl.), 2000,vol. 8, no. 1, pp. 13–29].Maslov, A.V., Osadochnye porody: metody izucheniya i inter�pretatsii poluchennykh dannykh (Sedimentary Rocks: Anal�ysis Technique and Interpretation of Derived Data), Yekat�erinburg: UGGU, 2005.Maslov, A.V., Archean Metaterrigenous Rocks: MajorGeochemical Constraints, Geokhimiya, 2007, vol. 45, no. 4,pp. 370�389 [Geochem. Int. (Engl. Transl.), 2007, vol. 45,no. 4, pp. 327–344].Maslov, A.V. and Isherskaya, M.V., Osadochnye assotsiatsiirifeya Volgo�Ural’skoi oblasti (usloviya formirovaniya i lito�fatsial’naya zonal’nost’) (Riphean Sedimentary Associa�tions of the Volga�Ural Area: Formation Conditions andLithofacies Zoning), Yekaterinburg: Inst. Geol. Geokhim.Ural. Otd. Ross. Akad. Nauk, 1998.Maslov, A.V. and Isherskaya, M.V., Riphean SedimentaryAssociations at the Eastern and Northeastern Margins of

the East European Platform, Russian J. Earth Sci, 2002,vol. 4, no. 4. (http:/www.agu.org/wps/rjes).Maslov, A.V., Olovyanishnikov, V.T., and Isherskaya, M.V.,Riphean of Eastern, Northeastern and Northern Rims ofthe Russian Platform and Western Megazone of the Urals:Lithostratigraphy, Formation Conditions and Types of Sed�imentary Successions, Litosfera, 2002, no. 2, pp. 54–95.Maslov, A.V., Krupenin, M.T., Gareev, E.Z., andPetrov, G.A., Assessment of Redox Conditions in 89, no. 2,pp. 180–183].Maslov, A.V., Krupenin, M.T., Ronkin, Yu.L., et al., TheREE, Cr, Th and Sc in Glay Shales of the Riphean Strato�type as Indicator of Composition and Evolution of SourceAreas, Litosfera, 2004a, no. 1, pp. 70�112.Maslov, A.V., Krupenin, M.T., Ronkin, Yu.L., Gareev, E.Z.,Lepikhina, O.P., and Popova, O.Yu., Fine�Grained Alumi�nosiliciclastic Rocks of the Middle Riphean Stratotype Sec�tion in the Southern Urals: Formation Conditions, Compo�sition and Provenance Evolution, Litol. Polezn. Iskop.,2004b, vol. 39, no. 4, pp. 414–441 [Lith. Mineral. Res. (Engl.Transl.), 2004b, vol. 39, no. 4, pp. 357–381].Maslov, A.V., Ronkin, Yu.L., Krupenin, M.T., Gareev, E.Z.,and Lepikhina, O.P., The Lower Riphean Fine�GrainedAluminosilicate Clastic Rocks of the Bashkir Anticlinoriumin the Southern Urals: Composition and Evolution of TheirProvenance, Geokhimiya, 2004c, vol. 42, no. 6, pp. 648–669[Geochem. Int. (Engl. Transl.), 2004c, vol. 42, no. 6,pp. 561–578].Maslov A.V., Gareev E.Z., Krupenin M.T. Terrigenous Sed�imentary Sequences in the Riphean Stratotype: Contribu�tion of Recycling and Input of the First Cycle Material,Geokhimiya, 2005, vol. 43, no. 2, pp. 158–181 [Geochem.Int. (Engl. Transl.) 2005, vol. 43, no. 2, pp. 131–152].Maslov, A.V., Podkovyrov, V.N., Ronkin, Yu.L.,Krupenin, M.T., Gareev, E.Z., and Gorozhanin, V.M.,Secular Variations of the Upper Crust Composition: Impli�cation of Geochemical Data on the Upper PrecambrianShales from the Southern Urals Western Flank and Uchur–Maya Region, Stratigr. Geol. Korrelyatsiya, 2006, vol. 14,no. 2, pp. 26–51 [Stratigr. Geol. Correlation (Engl. Transl.),vol. 14, no. 2, pp. 126–149].Maslov, A.V., Gareev, E.Z., Krupenin, M.T., and Ronkin,Yu.L., Realtime Lithogeochemical Features of UpperRiphean Shales and Mudstones of the Bashkir Anticlino�rium, Litosfera, 2007, no. 5, pp. 38–67.Maslov, A.V., Isherskaya, M.V., Ronkin, Yu.L., and Lepi�khina, O.P., The REE, Cr, Ni, Co, Sc, Hf, and Th System�atics of the Upper Vendian Fine�Grained Aluminosilici�clastic Rocks in the Shkapovo�Shikhany Depression, Izv.Vyssh. Uchebn. Zaved., Geol. Razved., 2008, no. 2, pp. 20–27.Michurin, S.V., Genesis of Sulfates and Sulfides in LowerRiphean Rocks of the Kama�Belaya Aulacogen, PhD(Geol.�Miner.) Dissertation, Moscow: Geol. Inst. Ross.Akad. Nauk, 2008.Nesbitt, H.W., Mobility and Fractionation of Rare Ele�ments during Weathering of a Granodiorite, Nature, 1979,vol. 279, pp. 206–210.Nesbitt, H.W. and Young, G.M., Early Proterozoic Cli�mates and Plate Motions Inferred from Major ElementChemistry of Lutites, Nature,. 1982, vol. 299, pp. 715–717.Ozhiganova, L.D., Petrographic�Mineralogical Studies ofAncient Rocks, in Drevnie otlozheniya Zapadnoi Bashkirii

(Ancient Rocks of Western Bashkiria), Ufa: Bashkir. Fil.Akad. Nauk SSSR, 1960, pp. 28–82.

Ozhiganova, L.D., Lower Riphean of Western Bashkiria, inStratigrafiya i litologiya verkhnego dokembriya i paleozoyaYuzhnogo Urala i Priural’ya (Upper Precambrian and Pale�ozoic Stratigraphy and Lithology in the Southern Urals andCis�Ural Region), Ufa: Bashkir. Fil. Akad. Nauk SSSR,1983, pp. 33–39.

Panahi, A. and Young, G.M., A Geochemical Investigationinto the Provenance of the Neoproterozoic Port Askaig Til�lite, Dalradian Supergroup, Western Scotland, PrecambrianRes., 1997, vol. 85, pp. 81–96.

Peter, J.M., Ancient Iron Formations: Their Genesis andUse in The Exploration for Stratiform Base Metal SulphideDeposits, with Examples from the Bathurst Mining Camp,in Geochemistry of Sediments and Sedimentary Rocks: Evolu�tionary Considerations to Mineral Deposit�Forming Environ�ments, Lentz, D.R., Ed., GeoText 4. Geol. Assoc. Canada,2003, pp. 145–176.

Postnikova, I.E., Verkhnii dokembrii Russkoi plity i egoneftenosnost' (Upper Precambrian of the Russian Plate andPetroleum Potential), Moscow: Nedra, 1977.

Rabochaya skhema stratigrafii i korrelyatsii razrezov verkh�nego proterozoya Zapadnoi Bashkirii (metodicheskie reko�mendatsii) (Working Scheme of Stratigraphy and Correla�tion of Upper Proterozoic Sections in Western Bashkiria),Lisovskii, N.N., Ed., Ufa: Bashkir. Fil. Akad. Nauk SSSR,1981.

Rachold, V. and Brumsack, H.�J., Inorganic Geochemistryof Albian Sediments from the Lower Saxony Basin NWGermany: Palaeoenvironmental Constraints and OrbitalCycles, Palaeogeogr. Palaeoclimat. Palaeoecol., 2001,vol. 174, pp. 121–143.

Rimmer, S.M., Geochemical Paleoredox Indicators in Devo�nian�Mississippian Black Shales, Central Appalachian Basin(USA), Chem. Geol., 2004, vol. 206, pp. 373–391.

Rock, N.M., Webb, J.A., McNaughton, N.J., et al., Non�parametric Estimation of Averages and Errors for SmallDatasets in Isotope Geoscience: A Proposal, Chem. Geol.,1987, vol. 66, pp. 163–177.

Romanov, V.A. and Isherskaya, M.V., K izucheniyurifeiskikh otlozhenii Zapadnoi Bashkirii (Study of RipheanRocks in Western Bashkiria), Ufa: Inst. Geol. Ufim.Nauchn. Tsentra Ross. Akad. Nauk, 1994.

Romanov, V.A. and Isherskaya, M.V., Stratigrafiya rifeyaplatformennogo Bashkortostana (Riphean Stratigraphy ofPlatform Bashkortostan), Ufa: Inst. Geol. Ufim. Nauchn.Tsentra Ross. Akad. Nauk, 1998.

Romanov, V.A. and Isherskaya, M.V., Riphean Stratigraphyof Platformal Bashkortostan, in Stratigrafiya, paleontologiyai perspektivy neftegazonosnosti rifeiskikh i vendskikh otlozhe�nii vostochnoi chasti Vostochno�Evropeiskoi platformy(Stratigraphy, Paleontology, and Petroleum Potential ofRiphean and Vendian Rocks in the Eastern East EuropeanPlatform), Ufa: Inst. Geol. Ufim. Nauchn. Tsentra Ross.Akad. Nauk, 1999, vol. 2, pp. 59–60.

Romanov, V.A. and Isherskaya, M.V., Rifei platformennogoBashkortostana: stratigrafiya, tektonika i perspektivy neftega�zonosnosti (Riphean of Platformal Bashkirtostan: Stratigra�phy, Tectonics, and Petroleum Potential), Ufa: Gilem,2001.

MASLOV et al.

Strakhov, N.M., Problemy geokhimii sovremennogo okean�skogo litogeneza (Problems of Geochemistry in ModernOceanic Lithogenesis), Moscow: Nauka, 1976.

Stratigraficheskaya skhema rifeiskikh i vendskikh otlozheniiVolgo�Ural’skoi oblasti. Ob’’yasnitel’naya zapiska (Strati�graphic Scheme of Riphean and Vendian Rocks in theVolga�Ural Area: Explanatory Note), Aksenov, E.M. andKozlov, V.I., Eds., Ufa: Inst. Geol. Ufim. Nauchn. TsentraRoss. Akad. Nauk, Tsentr. Nauchno�Issled. Inst. Geol�nerud, Bash. Nauchno�Issled. Proekt. Inst. Nefekxim.Prom., 2000.

Stratotip rifeya. Stratigrafiya. Geokhronologiya (The Riph�ean Type Section. Stratigraphy. Geochronology), Keller,B.M. and Chumakov, N.M., Eds., Moscow: Nauka, 1983.

Strekopytov, S.V., Dubinin, A.V., and Volkov, I.I., Behaviorof REE, Zircon, and Hafnium in Sediments and Nodules ofthe Transpacific Profile, Geokhimiya, 1995, vol. 33, no. 7,pp. 985–997.

Taylor, S.R. and MacLennan, S.M., The Continental Crust:Its Composition and Evolution, Oxford: Blackwell 1985.Translated under the title Kontinental’naya kora: ee sostav ievolyutsiya, (Continental Crust: Composition and Evolu�tion), Moscow: Mir, 1988.

Taylor, S.R. and McLennan, S.M., The Chemical Evolu�tion of the Continental Crust, Rev. Geophys., 19952, vol. 33,pp. 241–265.

Timergazin, K.R., Do devonskie obrazovaniya zapadnoiBashkirii i perspektivy ikh neftegazonosnosti (PredevonianRocks of Western Bashkiria and Petroleum Potential), Ufa:Bashkir. Fil. Akad. Nauk, SSSR, 1959.

Turgeon, S. and Brumsack, H.�J., Anoxic vs DysoxicEvents Reflected In Sediment Geochemistry during theCenomanian�Turonian Boundary Event (Cretaceous) in

the Umbria�Marche Basin of Central Italy, Chem. Geol.,2006, vol. 234, pp. 321–339.Visser, J.N.J. and Young, G.M., Major Element Geochem�istry and Paleoclimatology of the Permo�CarboniferousGlaciogene Dwyka Formation and Post�Glacial Mudrocksin Southern Africa, Palaeogeogr. Palaeoclimat. Palaeoecol.,1990, vol. 81, pp. 49–57.Valiev, Yu.Ya., Geokhimiya bora v yurskikh otlozheniyakhGissarskogo khrebta (Geochemistry of Boron in JurassicRocks of the Hissar Range), Moscow: Nauka, 1977.Verkhnii dokembrii vostochnykh raionov Tatarstana i perspe�ktivy ego neftegazonosnosti (Upper Precambrian of EasternRegions of Tatarstan and Its Petroleum Potential), Musli�mov, R.Kh., Ed., Ufa: Ufim. Nauchn. Tsentr Ross. Akad.Nauk, 1995.Walker, C.T. and Price N.B. Departure Curves for Comput�ing Paleosalinity from Boron in Illites and Shales, Am.Assoc. Petrol. Geol., 1963, vol. 47, pp. 833–841.Wronkiewicz, D.J. and Condie, K.C., Geochemistry ofArchean Shales from the Witwatersrand Supergroup, SouthAfrica: Source�Area Weathering and Provenance, Geochim.Cosmochim. Acta, 1987, vol. 51, pp. 2401–2416.Wronkiewicz, D.J. and, Condie, K.C., Geochemistry andMineralogy of Sediments from the Ventersdorp and Trans�vaal Supergroups, South Africa: Cratonic Evolution duringthe Early Proterozoic, Geochim. Cosmochim. Acta, 1990,vol. 54, pp. 343–354.Yanov, E.N., Geochemistry of the Caucasian and CrimeanFlysch, Litol. Polezn. Iskop., 1971, vol. 6, no. 1, pp. 84–101.Yudovich, Ya.E., Regional’naya geokhimiya osadochnykhtolshch (Regional Geochemistry of SedimentarySequences), Leningrad: Nauka, 1981.Yudovich, Ya.E. and Ketris, M.L., Osnovy litokhimii (Fun�damentals of Lithochemistry), St. Petersburg: Nauka, 2000.

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