Glaciogenic and Related Sedimentary Rocks: Main Lithochemical Features. Communication 2. The...

ISSN 0024�4902, Lithology and Mineral Resources, 2010, Vol. 45, No. 5, pp. 443–464. © Pleiades Publishing, Inc., 2010.Original Russian Text © A.V. Maslov, 2010, published in Litologiya i Poleznye Iskopaemye, 2010, No. 5, pp. 496–518.

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INTRODUCTION

Three great climatic stages are distinguished in theEarth’s history: Early and Middle Archean, LateArchean–Middle Riphean, and Late Riphean–Phan�erozoic (Chumakov, 2004b). Glaciation was likelyatypical for the first stage. The second stage wasmarked by episodic glaciations, whereas the thirdstage was characterized by frequent and periodic glaci�ations. The greatest glacial periods with the largestareas covered by glaciers and related sediments tookplace at the end of the Late Riphean (~740 Ma ago),Early Vendian (~600 Ma), Late Ordovician (maxi�mum at ~440 Ma), Late Paleozoic (~290 Ma), andLate Cenozoic. The last glaciation was maximal in thePleistocene (Chumakov, 2004b).

We analyzed the chemical compositions of glacio�genic and related rocks within a wide age range inorder to identify their common and/or specific fea�tures that could be used in various comparisons andgeneralizations. In view of a limited volume of thispaper, we report only data on objects, for which suffi�ciently representative analytical materials are avail�able. They were compared with the average Post�Archean Australian Shale (Taylor and McLennan,1985). One more tool in our investigations was thechemical index of alteration (CIA = 100 ×

Al2O3/(Al2O3 + CaO* + Na2O + K2O) (Nesbitt andYoung, 1982). High CIA values reflect the prevailingremoval of mobile elements (Ca2+, Na+, and K+), rel�ative to immobile elements (Al3+ and Ti4+), duringchemical weathering under warm humid climatic con�ditions. Low CIA values indicate an almost complete

absence of chemical weathering and, hence, can beindicators of cold and/or arid climate. Strongly weath�ered tropical clays have CIA values more than 80(Nesbitt and Young, 1982). The average cratonicshales, such as the Post�Archean Australian Shale(PAAS), North American Shale Composite (NASC),and Russian Platform Sample of Clays (RPSC), arecharacterized by CIA values within 70–75. Thisparameter is significantly lower (~60–65) in the gla�cial mudstones and as low as ~50 in the Pleistocenetills related to processes of physical (“mechanical”)weathering.

The first communication (Maslov, 2010) was dedi�cated to the consideration of lithochemical features ofthe Late Archean, Early–Late Proterozoic (Paleo�and Neoproterozoic) glaciogenic and related sedi�mentary rocks, which are known in sections of theWitwatersrand, Huronian, Transvaal, Dalradian,Huef, and Mirbat supergroups, as well as the Serebry�anka and Sylvitsa groups of the Middle Urals. It wasestablished that these rocks are characterized by anextremely wide CIA range (for instance, diamictitesand their fine�grained matrix have CIA from 54–56 to70–74) and widely varying chemical composition.The highest CIA value found in diamictites of theUpper Archean Coronation Formation is caused bythe predominance of redeposited sedimentary mate�rial in its composition.

As compared to PAAS, diamictites of the Corona�tion Formation are significantly depleted in CaO,Na2O, and K2O. In contrast, diamictites of theNeoproterozoic Ayn and Arkahawl formations withminimal CIA values are significantly enriched in Na2O

Glaciogenic and Related Sedimentary Rocks: Main Lithochemical Features. Communication 2. The Paleozoic and Cenozoic

A. V. MaslovZavaritskii Institute of Geology and Geochemistry, Uralian Division, Russian Academy of Sciences,

Pochtovyi per. 7, Yekaterinburg, 620075 Russiae�mail: [email protected]

Received July 20, 2009

Abstract—Lithochemical features of the Early–Late Paleozoic and Cenozoic glaciogenic and related sedi�mentary rocks around the world are considered. Comparison of the bulk chemical composition of diamictiteswith the average Post�Archean Australian Shale (PAAS) revealed that the diamictites do not show anylithochemical characteristics unambiguously indicating their formation under cool climatic conditions. Thechemical index of alteration (CIA) often used in the paleoclimatic reconstructions should be considered asadditional (though very important) tool, because it is controlled by local factors. Taking into account thesefacts, there are likely no grounds to expect that the amount of the redeposited sedimentary material in theLate Paleozoic and Cenozoic glaciogenic rocks is more than in their Early Proterozoic and Late Riphean–Vendian analogues.

DOI: 10.1134/S0024490210050044

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LITHOLOGY AND MINERAL RESOURCES Vol. 45 No. 5 2010

MASLOV

and virtually indistinguishable from the PAAS in termsof K2O. Diamictites of the Mineral Fork Formationare somewhat depleted in Na2O, but marked by widevariations in the CaO content. Diamictites of the PortAskaig Formation are enriched in CaO and depletedin Na2O. In contrast, he diamictites of the Fiq Forma�tion show depletion CaO and 1.2–1.9 times enrich�ment in Na2O relative to the PAAS. The fine�grainedmatrix of diamictites of the Lower Vendian TanninFormation from the Middle Urals shows no significantdepletion in CaO, Na2O, and K2O.

Fine�grained terrigenous rocks (shales, silty mud�stones, and mudstones) associated with diamictitesshow significant CIA variations (from 60–62 to 69–76). Relative to the PAAS, they are significantlydepleted in CaO and variably enriched in Na2O.

Data presented above indicate that the consideredrocks lack any specific lithochemical characteristicstypical of the Precambrian rocks that are undoubtedlyglaciogenic sediments from the point of view of tex�tural–structural indicators .

This communication is dedicated to analysis ofanalogous data on the Early–Late Paleozoic and Cen�ozoic glaciogenic and related sedimentary rocks.

THE EARLY PALEOZOIC

The third (Late Ordovician) “Great Glaciation”with peak at approximately 440 Ma occurred in the

Early Paleozoic. Glacial and related sediments of thisage are widespread in the Western and South Africa, aswell as in the South America (Earth’s…, 1981; Younget al., 2004). For instance, in the Western part of theCape fold belt in South Africa, the glaciogenic rocksunited into the Pakhuis Formation compose the upperpart of the Ordovician Table Mountain Group (Fig. 1)(Visser, 1974; Rust, 1981; Young et al., 2004). Totalthickness of rocks of the Pakhuis Formation reaches150 m. The presence of well�expressed sandy wedgesand “structured grounds” indicates the following fact:among two diamictite beds observed in the section, atleast the lowermost bed was accumulated under conti�nental settings and wide seasonal variations of temper�ature (Young et al., 2004). Rocks of the Pakhuis For�mation are overlapped and presumably replaced partlyalong the strike by rocks of the Cedarberg Formationmainly composed of mudstones.

The glaciogenic sediments of the Pakhuis Forma�tion are underlain and overlain by mineralogically andchemically very mature sandstones and mudstones(Visser, 1974; Marchant and Moore, 1978; Rust,1981), which are characterized by high CIA values(74–78) and relative depletion in Ca and Na, implyingtheir formation from material subjected to substantialchemical weathering (Young et al., 2004).

In general, the average chemical composition ofthe Pakhuis diamictite is similar to that of the averagecrust, except for significantly lower Na2О contents.The CIA value in the diamictites varies from 48–51 to76, with the lowest values found in the central part ofthe diamictite beds (Young et al., 2004). It is suggestedthat the high CIA values in some diamictite samplesreflect the presence of weathered material extractedfrom the underlying rocks.

The median contents of the major rock�formingoxides in rocks of the Pakhuis and Cedarberg forma�tions calculated using data (Young et al., 2004) arepresented in Table 1. In terms of SiO2, TiO2, Al2O3,Fe2O3tot, MgO, K2O, and P2O5, diamictites of thePakhuis Formation are similar to the PAAS, butmarked by elevated contents of CaO and significantlylower contents of Na2O (Fig. 2a). Mudstones of theCedarberg Formation are significantly depleted inCaO and Na2O relative to the PAAS (Fig. 2b).

THE LATE PALEOZOIC

One of the most significant biospheric rearrange�ments in the Phanerozoic occurred in the Permianand Early Triassic (Climate…, 2004). The onset of gla�ciation is dated at the Middle Carboniferous and thesouthern glacial belt reached its maximal width in theterminal Late Carboniferous–beginning of the EarlyPermian (Chumakov, 2004a). In the Asselian and Sak�marian time, glaciations occupied high and middlepaleolatitudes of South America, Africa, India, andAustralia (ice sheets at that time covered Transvaal,Botswana, Namibia, and later Antarctica). However,

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Fig. 1. Generalized section of sediments of the TableMountain and Bokkeweld groups. Modified after (Younget al., 2004). Inset shows relations between the Pakhuis andCedarberg formations. (1) Sandstones, (2) diamictites(with clay and sandy matrix); (3) shales and mudstones;(4) quartz arenites; (5) conglomerates.


GLACIOGENIC AND RELATED SEDIMENTARY ROCKS 445

the glacial sheet significantly decreased already in thesecond half of the Sakmarian and beginning of theArtinskian time. Global paleogeographical recon�structions for this time indicate a steady position of themain continental masses on the Earth, suggesting thatlarge�scale transformations in the biosphere were notcaused by cardinal paleotectonic events (Zharkov,2004). Their most striking manifestations are observedin sedimentary basins of South Africa, primarily, in theretro�arc foreland Karoo and Kalahari basins (Visser,1987, 1995; Cole, 1992; Scheffler et al., 2006; and oth�ers). According to Chumakov (2004a), evolution ofthe Late Paleozoic glaciations was presumably trig�gered by intensification of the explosive suprasubduc�tion volcanism and related sequence of “volcanic win�ters.”

In the southern part of the Karoo Basin, the KarooSupergroup unconformably overlying the Paleozoicbasement consists of the Dwyka (Upper Carbonifer�ous–Lower Permian), Ecca (Lower–Middle Per�mian), and Beaufort (Upper Permian–Lower Trias�sic) groups (Fig. 3) (Visser, 1987; 1995; Smith et al.,1993). Diamictites are widespread in the section of theDwyka Group (Huber et al., 2001). Typical Dwykadiamictites are rocks with well rounded, angular orsemiangular fragments of diverse magmatic, meta�morphic, and metasedimentary rocks and minerals(mainly quartz and sometimes feldspars) in a fine�grained matrix enriched in micaceous minerals. Pro�portions between the indicated components of diam�ictites in different areas of the Karoo Basin show sig�nificant variations (Reimold et al., 1997).

Along the periphery of the Karoo and Kalaharibasins and intervening rises, the Dwyka Group is rep�resented by continental glacial sediments. In centralparts of the basins, it has mainly glaciomarine compo�sition. Traces of iceberg rafting also occur in the lowerpart of the Prince Albert Formation (Zharkov, 2004).The diamictites associate with marine sediments (Vis�ser, 1989). The sharp contact between diamictites andoverlying rocks presumably indicates a rapid change insedimentation settings (Visser and Young, 1990;Scheffler, 2004).

The Dwyka Group combines four deglaciationsequences (DS) (Fig. 4), each of which consists of gla�cial and interglacial phases (Visser, 1997; Scheffleret al., 2003; Scheffler, 2004) represented by massivebasal diamictites and overlying mudstones, respec�tively. Duration of the DS formation is about 5–7 Ma(Bangert et al., 1999; Stollhofen et al., 2000; Scheffleret al., 2003; Scheffler, 2004). It is believed that thediamictites were accumulated in underwater fan nearthe of glacier thawing area (Visser, 1997).

During the formation of deglaciation sequences Iand II, the source areas were situated in the north(Cargonian Highlands), which were later replaced byprovenances located south of the Karoo Basin (mag�matic arc along the paleo�Pacific boundary) (Visser,1989, 1997; Scheffler et al., 2003; Scheffler, 2004).

Data on the chemical composition presented in(Scheffler, 2004) for different deglaciation sequencesin the Warmbad Basin and summarized in Table 2 tes�tify to their principle similarity, except for somewhathigher MgO content in rocks from the lowermost“deglaciation sequence.”

During the Ecca Group accumulation (thicknessup to 2000 m), the sedimentation area represented awide shelf (Smith et al., 1993), where dark gray mud�stones with cherts, as well as carbonate and phosphatenodules and lenses (Prince Albert Formation), wereaccumulated along the rising Cape foldbelt (Smithet al., 1993; Visser and Young, 1990). The overlyingWhitehill Formation is dominated by the pyritizedblack carbonaceous shales. The Collingham Forma�tion is represented by alternating siltstones and shales,which were accumulated in the distal fans and pelagicsettings (Catuneanu et al., 1998). The overlying Visch�kuil and Laingsburg formations combine shales, silt�stones, and sandstones, which compose well expressedregressive cycles (Smith et al., 1993). In the southwest�ern Karoo Basin, the Ecca Group is terminated by theFort Brown and Waterfront formations. They aremade up of shales and sandstones, which were accu�mulated mainly in the deltaic settings under the influ�ence of large river systems (Smith et al., 1993; Catu�neanu et al., 1998). Thus, during the accumulation ofsediments in the middle and upper parts of the EccaGroup, the influx of clastic material exceeded consid�erably the subsidence rate of the Karoo Basin, thus

Table 1. Median contents (%) of the major rock�forming oxidesand CIA values in the glaciogenic and associated sediments of thePakhuis and Cedarberg formations

Compo�nents

Pakhuis Formation, diamictites

Cedarberg Formation, mudstones

Md SD Md SD

SiO2 66.35 0.98 53.17 6.85

TiO2 0.61 0.10 0.91 0.36

Al2O3 11.38 2.25 20.33 4.94

Fe2O3tot 4.45 0.73 8.41 2.78

MnO 0.12 0.08 0.06 0.02

MgO 2.31 0.33 3.43 0.87

CaO 3.89 2.13 0.17 0.07

Na2O 0.05 0.19 0.06 0.03

K2O 3.76 0.52 5.41 1.31

P2O5 0.18 0.01 0.09 0.05

L.O.I. 5.62 1.19 5.73 1.51

Total 99.16 0.47 98.23 0.75

CIA 51 14 76 1

n 5 11

Note: Hereinafter, n is the number of analyzed samples.

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10

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(а)

10

1

0.1

(c)

SiO2 TiO2 Al2O3Fe2O3 MgO CaO Na2O K2O P2O5

(b)

(d)


Fig. 2. PAAS�normalized distribution of the major oxides in the glaciogenic and associated rocks. (a, b) Table Mountain Group,South Africa: (a) diamictites of the Pakhuis Formation, (b) mudstones of the Cedarberg Formation; (c, d) Upper Paleozoic sed�iments of the Karoo Basin: (c) diamictites of the Dwyka Group, central part of the basin, (d) mudstones of the Prince Albert For�mation, eastern part of the basin.

facilitating its subsequent filling with turbidite, deltaic,lacustrine, and alluvial sediments (Catuneanu et al.,1998; Scheffler, 2004).

In the terminal Permian, the wide alluvial plains(sediments of the Beaufort Group) covered virtuallythe entire Karoo Basin (Smith et al., 1993). Theresumed uplift of the southern and eastern prove�nances during the progressive aridization of climateproduced playa and dune sediments (Smith et al.,1993; Scheffler, 2004). Basalts of the DrakensbergGroup overlying sedimentary rocks of the KarooSupergroup are interpreted as precursors of the LateJurassic breakdown of Gondwana (Catuneanu et al.,1993; Turner, 1999).

The main minerals in the glaciogenic sediments ofthe Dwyka Group are quartz, albite, microcline, chlo�rite, and illite. The CIA value varies from 51 to 58. Inrocks from the upper part of the group, the amount ofK�feldspars and albite decreases, whereas the illitecontent significantly increases. The CIA value varieshere from 50 to 70. Sufficiently sharp CIA variations inthe Dwyka Group (Scheffler et al., 2003) point torapid transitions from the glacial to interglacial phases.In the transition zone between the Dwyka and Eccagroups, quartz, albite, and microcline virtually disap�pear, while the amount of clay minerals increases to50–55%, with the predominance of chlorite and illite.It is noteworthy that the clay minerals are represented

higher in the section by illite, kaolinite, and smectite,while chlorite is absent. Increase in CIA from rocks ofthe Dwyka Group to rocks of the Ecca Group indi�cates a growth of temperatures and humidization ofclimate in the paleodrainage areas, which facilitatedmore intense mobilization of elements during weath�ering (Figs. 5, 6). According to (Scheffler, 2004;Scheffler et al., 2006), the high content of clay miner�als and quartz in the boundary beds between theDwyka and Ecca groups could result from a change insedimentation and climatic settings, while the com�plete disappearance of potassic feldspars in rocks ofthe uppermost portion of the Dwyka Group indicatessufficiently intense chemical weathering in the pale�odrainage areas. The highest CIA (~80) was noted inrocks from the upper part of the Prince Albert Forma�tion (Scheffler et al., 2006). Intense chemical weath�ering also accompanied accumulation of the Whitehillrocks (CIA = 65–75). Rocks in the upper part of theWhitehill Formation and lower part of the CollinghamFormation were formed when arid conditions pre�vailed in the paleodrainage areas, as suggested by thesignificantly lower CIA (~65) in sediments of the Col�lingham Formation.

Median contents of the major rock�forming oxidesin rocks of the Dwyka Group and Prince Albert For�mation in the Karoo Basin calculated from materialsin (Hubert et al., 2001; Scheffler, 2004) are presentedin Table 3. Rocks of the Dwyka Group after the PAAS



normalization are subdivided into several groups ofdifferent compositions (Fig. 2c). One group is charac�terized by enrichment in CaO and sharp depletion inNa2O. Rocks of other groups show moderate enrich�ment in Na2O and the PAAS�level contents of mostother rock�forming oxides. Fine�grained rocks of thePrince Albert Formation from the eastern KarooBasin are significantly enriched in Fe2O3tot. In all ana�lyzed samples, the Na2O content is significantly lower,while CaO shows both higher and lower values relativeto the PAAS (Fig. 2d).

In the Warmbad Basin (southern Namibia), theUpper Carboniferous–Lower Permian sequence isrepresented by glacial sediments of the Dwyka Group,as well as rocks of the Prince Albert and Whitehill for�mations (Scheffler, 2004). In this area, the main min�eral phases in rocks of the Dwyka Group are quartz,albite, and illite. Chlorite, kaolinite, calcite, and dolo�mite are subordinate (Geiger, 2000).

Table 4 presents median contents of the majorrock�forming oxides in rocks of the Dwyka Group, aswell as the Prince Albert and Whitehill formations, inthe Warmbad Basin obtained by recalculation of datafrom (Scheffler, 2004). It is seen that upward theKaroo Supergroup, the rocks reveal a significantincrease in SiO2, sharp decrease in Fe2O3tot, and lessdistinct decrease in Al2O3 and MgO. All three lithos�tratigraphic units mentioned above have low medianCaO contents (0.49, 0.35, and 0.37). However, highervalues of the standard deviation indicate their signifi�cant variations. The Na2O and K2O values are evenlydistributed throughout the section.

Values of the Si/Al and Na/Al ratios in rocks of theDwyka Group in the Warmbad Basin approximatelycorrespond to those in the average post�Archeanshales (NASC, PAAS, and others), whereas glacialsediments from the Karoo Basin are significantlyenriched in Si and Na. In the Karoo Basin, ratios ofalkaline and alkaline earth elements to Al show cyclicvariations that are not observed in rocks of the Warm�bad Basin. In addition, glacial and interglacial sedi�ments in the southern Karoo Basin can be distin�guished using the Na/Al ratio, whereas variations ofthis ratio are indistinct in the Warmbad Basin section(Scheffler, 2004). The low Si/Al values in rocks of theDwyka Group in the Warmbad Basin are related to thehigh content of clay minerals, which can be explainedby low sedimentation rates. In contrast, rocks of theDwyka Formation in the Karoo Basin have signifi�cantly higher Si/Al values. In the Karoo Basin,decrease in the element/Al ratio at the boundarybetween the Dwyka and Ecca rocks is considered indi�cator of climatic changes (Scheffler, 2004). At thesame time, this feature is absent in sediments of theWarmbad Basin.

A common feature of the Dwyka Group, as well asthe Prince Albert and Whitehill formations, in theWarmbad Basin is significant depletion in CaO ascompared to PAAS. In addition, rocks of the Whitehill

Formation are often depleted in Fe2O3tot and MgO(Figs. 7a, 7b). Rocks of different deglaciationsequences of the Dwyka Group are characterized bysignificantly lower CaO contents as compared toPAAS (Figs. 7c, 7d).

Rocks of the Dwyka Group in the Warmbad Basinhave extremely high (73–86) CIA values (Scheffler,2004), whereas the median CIA in normal shales is~76 (Nesbitt and Young, 1982). This fact indicates thepresence of a significant amount of clay minerals pre�sumably derived from the redeposited sedimentarymaterial. In sediments from the upper part of thePrince Albert Formation and in the Whitehill Forma�tion section, the CIA value decreases from ~80 to 72.This trend is approximately consistent with change ofpaleoclimatic indicators in sediments from the south�ern Karoo Basin.

The Brazilian Paraná Basin is filled with three largesedimentary sequences: Silurian–Devonian, UpperCarboniferous–Jurassic, and Cretaceous (Eyles et al.,1993). Basal levels of the Upper Carboniferous—

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Fig. 3. Schematic stratigraphic column of rocks of theKaroo Supergroup in the Karoo Basin. Modified after(Scheffler et al., 2006). (I–IV) “Deglaciation sequences”.Formations: (1) Whitehill, (2) Collingham, (3) Vischkuil;(4) Laingsburg; (5) Fort Brown, (6) Waterfront.

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Dry and cold Wet

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1

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Transgression

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Transgression

Transgression

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Fig. 4. CIA distribution in rocks of the Dwyka Group (Karoo Basin). Modified after (Scheffler et al., 2003). (1) Massive diamic�tites; (2) bedded diamictites; (3) rock fragments. (I–IV) “Deglaciation sequences.” Numbers in the stratigraphic column showthe values of absolute age, Ma: (1) ~307, (2) 302 ± 3.2, (3) 297 ± 1.8; (4) 288 ± 3 and 289.6 ± 3.8.

Table 2. Median contents (%) of the major rock�forming oxides and CIA values in the “deglaciation sequence” of the DwykaGroup (Warmbad Basin)

Components DS Dwyka IDS Dwyka II DS Dwyka III DS Dwyka IV

Md SD Md SD Md SD

SiO2 58.09 61.67 4.47 62.25 3.68 62.00 3.61

TiO2 0.81 0.76 0.06 0.70 0.15 0.79 0.13

Al2O3 18.56 17.32 1.46 17.65 2.79 18.5 2.85

Fe2O3tot 8.12 7.05 0.87 6.30 2.06 6.47 3.26

MnO 0.05 0.05 0.44 0.06 0.48 0.11 0.06

MgO 3.31 2.65 0.36 2.27 0.77 2.28 0.66

CaO 0.67 0.47 1.12 0.50 4.03 0.50 0.87

Na2O 1.43 1.49 0.38 1.14 0.32 1.43 0.54

K2O 3.97 3.55 0.49 3.56 0.94 3.36 1.36

P2O5 0.15 0.12 0.02 0.11 2.88 0.13 0.05

L.O.I. 5.81 5.52 2.19 6.18 1.08 4.49 0.86

Total 100.98 100.52 0.44 100.66 0.31 100.72 0.42

CIA 70 70 5 72 12 73 7

n 1 19 17 12

Lower Permian Itararé Group (thickness up to 1400 m)is represented here by glacial and glaciomarine sedi�ments, which are replaced upsection by marine sedi�ments of the Guata and Passa dois groups. The alter�nation of substantially mudstone and diamictite bedsin the Itararé Group section indicates a frequent alter�

nation of cold (glacial) and more moderate climaticepochs (Zalán et al., 1990). This is typical of sedimentsof the Dwyka Group, its counterpart in South Africa.The Guata Group is mainly composed of deltaic sand�stones of the Rio Bonito Formation and siltstones ofthe Palermo Formation. The latter are overlain by oil�



bearing shales of the Irati Formation, which belong tothe Passa Dois Group (Eyles et al., 1993).

Median contents of the major rock�forming oxidesin rocks of the Itararé Group calculated from data in(Scheffler, 2004) are shown in Table 3. High Na and Kcontents in the glacial and postglacial sediments of theItararé Group and Tatui Formation related to the

presence of illite, Na�smectite, and feldspars areresponsible for the sufficiently high K/Al ratio.Decrease of the Na and K contents in the postglacialsediments correlates well with the inferred intensifica�tion of weathering in the paleodrainage areas (Schef�fler, 2004). The Irati Formation was presumably accu�mulated under warm humid conditions, whereas the

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160 m

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0 м50 70 90

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i a

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Fig. 5. CIA distribution in the Dwyka Group section andin the boundary Dwyka Group–Prince Albert Formationinterval. Modified after (Scheffler et al., 2006). (1) PrinceAlbert Formation.

Table 3. Median contents (%) of the major rock�forming oxides and CIA values in the glaciogenic and associated sediments ofthe Dwyka and Itararé groups and the Prince Albert formation

Com�ponents

Dwyka Group, diamictites, central Karoo Basin

Prince Albert Formation,mudstones, east of the Karoo Basin

Dwyka Group, diamictites, eastern Karoo Basin

Itararé Group, diamictites, Paraná Basin

Md SD Md SD Md SD Md SD

SiO2 67.90 3.61 54.54 15.61 65.24 15.47 79.69 5.50TiO2 0.70 0.06 0.59 0.20 0.66 0.21 0.52 0.24Al2O3 13.10 1.63 16.39 4.67 13.66 2.92 9.44 2.24Fe2O3tot 5.26 1.63 10.31 13.87 5.99 5.51 1.82 0.91MnO 0.11 0.02 0.36 2.60 0.08 2.68 0.01 0.01MgO 2.61 0.59 1.18 0.76 2.59 0.75 0.46 0.30CaO 2.01 0.56 0.80 3.59 1.88 4.85 0.48 0.09Na2O 2.76 0.79 0.04 0.20 2.45 1.39 1.70 0.52K2O 2.52 0.56 2.345 1.44 2.78 0.93 2.11 0.40P2O5 0.16 0.02 0.412 2.01 0.171 3.45 0.12 0.06L.O.I. 2.43 2.00 5.98 3.93 0.012 2.11 0.012 0.001Total 99.80 0.25 99.25 1.52 99.40 1.06 96.46 0.79CIA 62 6 78 16 54 14 60 1

n 23 12 18 3

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DwykaGroup

1

2

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4

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Fig. 6. CIA distribution in sediments of the Karoo Sub�group. Modified after (Scheffler et al., 2006). Formations:(1) Prince Albert; (2) Whitehill, (3) Collingham, (4) Vis�chkuil.

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MASLOV

aluminosilicate component of rocks of this lithostrati�graphic unit consists mainly of clay minerals. The lowNa/Al and K/Al ratios in rocks of the Irati Formationare related to the presence of kaolinite in the carbon�ate�free samples.

Glacial deposits of the Itararé Group demonstratesan upsection growth of the Zr/Ti ratio, which reachesmaximal values (~0.15) at the boundary between gla�cial and postglacial rocks (Scheffler, 2004). The inter�related CIA increase suggests that this parameter inrocks of the Itararé Group is controlled by the rockcomposition in source areas. As compared to thePAAS, rocks of the Itararé Group are depleted in TiO2,Al2O3, Fe2O3tot, MgO, and CaO (Fig. 7f) and insignif�icantly enriched in Na2O.

THE LATE CENOZOIC

As is known, the formation of ice sheet of Antarc�tica is related to the gradual (multistage) isolation ofthis part of land by currents and tectonic events fromthe surrounding regions (Kennett, 1977; Hambreyand Barrett, 1993; Zachos et al., 2001). The first sig�nificant glaciation in East Antarctic occurred at theend of Eocene–beginning of Oligocene (~34 Ma ago)(Ehrmann, 1991; Breza and Wise, 1992; Dingle andLavelle, 1998). Three glacial events are inferred forWest Antarctica, and the earliest glaciation took placein the Early–Middle Eocene (Birkenmajer, 1992;Jonkers et al., 2002; Troedson and Riding, 2002).

In order to decipher paleoclimatic changes, Dingleand Lavelle (1998) studied variations of the CIA andmaturity index (SiO2/Al2O3) in the Aptian–Pliocenesediments of the Antarctic Peninsula. Median contents

of the major rock�forming oxides and CIA values inrocks of different lithostratigraphic units of the indi�cated sedimentary sequence calculated using data from(Dingle and Lavelle, 1998) are presented in Table 5.

The CIA variations were used to reconstruct severalcycles of changes in the chemical composition of prov�enance (Fig. 8). In particular, rocks of the KotickPoint Formation (Aptian–Albian) are characterizedby sufficiently high CIA values (>70). In the Santo�nian–Late Maastrichtian and in the Late Paleocene–Middle Eocene, erosion involved the deeply weath�ered rocks (CIA >70). These time intervals are sepa�rated by periods, when chemical weathering was lessintense (CIA ~65). Rocks of the Middle Campanianand Early Maastrichtian, as well as the Santonian andearly Paleocene, reveal some signs of short�termevents, which provoked the formation of sedimentswith low (~60) and high (more than 70) CIA values.Post�Eocene sediments of the South Shetland Islandsand Ross Island have CIA values typical of the glacialand interglacial settings (Dingle and Lavelle, 1998). Inparticular, rocks of the Early Oligocene Polonez CoveFormation are characterized by CIA values between50 and 65, and they contain diamictites with CIA ~50.The glaciogenic Cape Melville (Late Oligocene–Early Miocene), Hobbs Glacier (Miocene) and Wed�dell (Quarter) formations are composed of sedimentswith CIA = 60–65. At the same time, the interglacialsediments, for instance, the Pliocene Pecten con�glomerates and rocks of the Late Oligocene Destruc�tion Bay Formation are characterized by the CIA valueof ~60 (Dingle et al., 1997). Note that CIA is not cor�related with geochemical indicators of rock composi�tion of the paleodrainage areas (Zr/TiO2, La/V), indi�

Table 4. Median contents (%) of the major rock�forming oxides and CIA values in the glaciogenic and related sediments of theDwyka Group and the Prince Albert and Whitehill formations (Warmbad Basin)

Compo�nents

Dwyka Group, diamictites Prince Albert Formation, mudstones Whitehill Formation, mudstones

Md SD Md SD Md SD

SiO2 62.15 3.91 63.27 3.70 68.6 3.61

TiO2 0.74 0.12 0.64 0.15 0.67 0.13

Al2O3 17.62 2.34 17.9 2.79 14.52 2.08

Fe2O3tot 6.61 2.09 5.70 2.04 0.71 1.36

MnO 0.07 0.39 0.05 0.2 0.01 0.02

MgO 2.38 0.63 1.78 0.27 0.63 1.42

CaO 0.49 2.48 0.35 0.34 0.37 1.21

Na2O 1.32 0.44 1.34 0.37 1.99 0.91

K2O 3.55 0.93 3.28 0.83 3.39 0.79

P2O5 0.119 1.70 0.10 0.16 0.10 0.06

L.O.I. 5.43 1.67 5.04 0.92 6.71 2.40

Total 100.68 0.39 100.43 0.44 100.33 0.62

CIA 71 9 73 2 67 8

n 49 28 20



cating the climatic nature of CIA variations (Dingleand Lavelle, 1998).

The results of comparison of chemical compositionof the Maastrichtian–Pliocene sediments of the Ant�arctic Peninsula with the PAAS composition areshown in Fig. 9. It is seen that the medianAl2O3/Al2O3PAAS ratio shows weak growth upward thesection. The lowest value of this ratio (0.59) was foundin sediments of the La Meseta Formation, whereas themaximal values (0.85 and 0.83) were found in theMagda Nunatak and Cockburn Island rocks. Themedian CaOsample/CaOPAAS value shows upsectiongrowth from ~1.0 in rocks of the Snow Hill Island For�mation to ~6.0 in the sediments of the CockburnIsland Formation. The Na2Osample/Na2OPAAS ratioincreases in the same direction (from 1.8 to 3.1). Themedian K2Osample/K2OPAAS ratio remains virtually

constant (~0.7 × PAAS) in rocks of the Maastrich�tian–Eocene interval and sharply decreases in rocks ofthe Polonez Cove and Magda Nunatak formations.Upsection, however, they again increase up to almostinitial values.

Based on analysis of the SiO2/Al2O3 ratio, Dingleand Lavelle (1998) concluded that lithochemicallymature (SiO2/Al2O3 > 6.0) sediments were accumu�lated in the Late Campanian–Early Maastrichtianand in the Middle Paleocene (Snow Hill Island andSobral formations). In the Late Maastrichtian–EarlyPaleocene rocks (Lopez de Bertodano Formation),this parameter varies from 5.5 to 6.9. A significant partof rocks of the Late Eocene La Meseta Formationhave the SiO2/Al2O3 ratio of >7.0 (maximum ~10.0),suggesting that they are lithochemically mature sedi�ments. In contrast, this ratio varies from 3.0 to 5.0 in

10

1

0.1

(c)

10

1

0.1

(e)


(d)

(f)


10

1

0.1

(а) (b)

WhitehillFormation

Dwyka 1

Fig. 7. PAAS�normalized patterns of the major oxide contents in the glaciogenic and associated rocks. (a–e) Warmbad Basin:(a) diamictites of the Dwyka Group; (b) mudstones of the Prince Albert and Whitehill formations; (c) “deglaciation sequences”I and II of the Dwyka Group; (d) “deglaciation sequence” III of the Dwyka Group; (e) “deglaciation sequence” IV of the DwykaGroup; (f) diamictites of the Itararé Group of the Paraná Basin.

452


MASLOV

Table 5. Median contents (%) of the major rock�forming oxides and CIA values in the glaciogenic and associated Maastrich�tian–Pliocene sediments in the northern Antarctic Peninsula

Compo�nents

Snow Hill Island Formation

Lopez de Ber�todano Formation Sobral Formation Cross Valley

FormationLa MesetaFormation

Polonez Cove Formation

Md SD Md SD Md SD Md SD Md SD Md SD

SiO2 68.28 2.49 69.68 2.28 68.93 4.87 53.98 4.48 74.62 5.47 49.80 4.38

TiO2 0.77 0.07 0.73 0.05 0.71 0.12 1.07 0.17 0.68 0.21 0.69 0.12

Al2O3 12.47 1.11 13.04 0.87 11.60 2.46 17.27 1.50 11.08 2.36 14.27 2.92

CaO 1.39 0.57 1.48 0.27 1.83 0.71 2.00 1.71 1.25 0.37 6.35 1.94

Na2O 2.12 0.52 2.14 0.18 2.27 0.41 2.73 0.35 1.82 0.30 1.95 0.61

K2O 2.61 0.13 2.68 0.29 2.65 0.22 1.48 0.82 2.59 0.21 0.41 0.58

CIA 67 4 68 3 63 6 72 5 64 5 63 9

n 20 15 6 3 16 8

Compo�nents

Magda NunatakFormation

Destruc�tion Bay

Formation

Cape Melville Formation Hobbs GlacierFormation

Cockburn IslandFormation

Md SD Md SD Md SD Md SD

SiO2 53.17 7.04 51.51 65.06 4.42 63.66 5.25 52.27 2.53

TiO2 0.74 0.07 1.12 0.65 0.09 1.04 0.18 1.96 0.05

Al2O3 16.05 0.78 17.11 13.62 1.64 13.14 0.40 15.69 0.58

CaO 5.24 2.23 7.40 3.29 1.60 3.28 0.62 8.06 0.17

Na2O 3.65 1.59 4.30 2.52 0.26 2.82 0.45 3.73 0.01

K2O 0.45 1.00 1.19 2.48 0.37 1.87 0.23 1.23 0.04

CIA 59 1 57 62 1 63 2 55 1

n 3 1 2 2 2

rocks of the post�Eocene glacial sequences, which istypical of immature and/or weakly mature rocks.

The study of core material derived from boreholesat the periphery of Antarctica and deep drilling dataalso give grounds to suggest that glaciation began inthe Late Eocene (Passchier, 2004). It was establishedthat the degree of detrital material weathering steadilydecreased from the Late Eocene to Late Oligocene(Ehrmann and Mackensen, 1992; Robert and Cham�ley, 1992; Passchier and Krissek, 2008).

In the Transantarctic Mountains, which separatethe East Antarctic Craton and the younger WesternAntarctic blocks, glacial deposits are represented bythe Middle Miocene Sirius Group, which unconform�ably rests on the metamorphic basement, deformedsandstones and mudstones of the Beacon Supergroup(Devonian–Triassic), and dolerites of the JurassicFerrar Formation with glacial striation (Passchier,2004).

Sections of the Sirius Group are mainly composedof diamictites, pebbly sands, and fine�grained sedi�ments of continental and shallow�marine glacial

genesis (Fig. 10) (Mayewski and Godthwait, 1985;McKelvey et al., 1991; Webb et al., 1996a, 1996b;Stroeven and Prentice, 1997; Wilson et al., 2002). Inparticular, the Sirius Group is represented near MountSirius by vaguely stratified diamictites (with pebbles upto 4 m across) alternating with lenses of pebbly brec�cias and conglomerates and several siltstone interbeds(Passchier, 2004). In the Shackleton glacier area,rocks of the Sirius Group outcrop in cliffs up to 100 mhigh and combine a wide spectrum of lithofacies rang�ing from massive diamictites to laminites. In theMount Feather area, the Sirius Group includes a40�m�thick sequence of bouldery diamicton withlocally observed signs of thin stratification and numer�ous faceted fragments with striation (Brady and McK�elvey, 1983; Wilson et al., 2002).

Median contents of the major rock�forming oxidesin sediments of the Sirius Group calculated from data(Passchier, 2004) are summarized in Table 6. As com�pared to the upper crust (Wedepohl, 1995), rocks ofthe Sirius Group are depleted in MgO, CaO, MnO,Na2O, Fe2O3, P2O5, Cr, Sr, and Nb, but they are



Ma

0

10

30

40

50

60

70

80

90

100

110

120

Pliocene

Miocene

Oligocene

Eocene

Paleogene

Maastrichtian

Campanian

SantonianConiacianTuronian

Cenomanian

Albian

Aptian

Formation

WeddellCockburn Island

Hobbs Glacier

Cape Melville

Destruction Bay

Magda NunatukPolonez Cove

La Meseta

Hiatus

Cross Valley

Sobral

Lopez de Bertodano

Snow Hill Island

Santa Marta

Hidden Lake

Whisky Bay

Kotick Point

Pleistocene tillsPleistoceneglacial clays

Average shales(PAAS, NASC, and others)

Tropical shales

CIA40 60 80

le

m

l

l

l

e

e

e

e

m

l

20

Fig. 8. CIA distribution in the Cretaceous and Cenozoic sediments of the northern Antarctic Peninsula. Modified after (Dingleand Lavelle, 1998). (e) early, (m) middle; (l) late.

454


MASLOV

enriched in SiO2. They are also characterized by aninsignificant relative decrease in the contents of TiO2,Al2O3, K2O, Y, and Zr. These features are presumablyrelated to the presence of a small amount of mechani�cally and chemically instable minerals. The clay frac�tion of diamictites of the Sirius Group in the central

Transantarctic Mountains is represented mainly byillite (Passchier, 2002, 2004). The K2O/Al2O3 ratio,which indicates the degree of sedimentary materialredeposition, is typically less than 0.23 in rocks of theSirius Group. Hence, rocks of the Sirius Group aremainly composed of erosion products of highly mature

10

1

0.1

(g)

SiO2 TiO2 Al2O3 CaO Na2O K2O

(h)

SiO2 TiO2 Al2O3 CaO Na2O K2O

(f)

(d)

(b)

10

1

(e)

10

1

(c)

0.1

0.1

10

1

(а)

0.1

Fig. 9. PAAS�normalized patterns of the major oxide contents in the glaciogenic and related Maastrichtian–Pliocene rocks inthe northern Antarctic Peninsula. (a–h) Formations: (a) Snow Hill Island; (b) Lopez de Bertodano; (c) Sobral; (d) La Meseta;(e) Polonez Cove; (f) Magda Nunatak; (g) Hobbs Glacier; (h) Cockburn Island.



sedimentary rocks. At the same time, rocks in thesouthern Transantarctic Mountains are characterizedby the K2O/Al2O3 ratio of 0.28–0.35, which is pre�sumably related to the local erosion of alkaline volca�nics.

The PAAS�normalized values for rocks of the Sir�ius Group are commonly marked by enrichment inCaO, elevated content of Na2O, and lowered content

of K2O (Figs. 11a–11c). Only in the vicinity of theReedy Glacier, the group contains rocks with differentdegrees of depletion in TiO2, Al2O3, FeO, and K2O, aswell as wide variation in contents of MgO, CaO, andNa2O (Fig. 11d).

The CIA value varies from 41 to 74 in sediments ofthe Sirius Group. Most of the diamictites are charac�terized by relatively high CIA values (56–70), indicat�

20 m

TilliteSpur

QuartzHills

BennettPlatform

Meyer Desert

Oliver Bluffs Mount

Sirius

1 2 3 4 5

Fig. 10. Proxy sections of the Sirius Group in the Transantarctic Mountains. Modified after (Passchier, 2004). (1) Diamictites;(2) gravelstones and sands with gravel; (3) sands and sandy clays; (4) clays and mudstones; (5) paleosol horizons.

Table 6. Median contents (%) of the major rock�forming oxides and CIA values in the glaciogenic and associated sediments ofthe Sirius Group (Transantarctic Mountains)

Com�ponents

Robert Massif area Bennett Platform area Dominion Range area Mount Sirius Dry Valley Reedy Glacier area

Md SD Md SD Md SD Md SD Md SD Md SD

SiO2 65.36 0.76 65.25 2.28 59.26 3.39 65.68 3.36 74.88 3.96 69.96 6.44

TiO2 0.66 0.04 0.71 0.05 0.58 0.03 0.59 0.05 0.40 0.17 0.83 0.17

Al2O3 14.90 0.20 13.19 0.66 13.17 1.30 12.51 0.87 8.47 4.79 13.93 1.58

Fe2O3tot 5.13 0.66 5.47 0.99 5.02 0.63 4.125 0.50 2.70 0.47 3.80 1.42

MnO 0.08 0.02 0.10 0.01 0.09 0.01 0.05 0.01 0.04 0.01 0.06 0.03

MgO 2.27 0.14 2.51 0.59 2.44 0.86 1.565 0.16 1.39 0.91 0.90 0.89

CaO 2.88 0.90 3.91 1.02 4.00 1.37 2.17 0.47 2.02 1.23 0.46 1.27

Na2O 1.81 0.13 1.90 0.18 1.91 0.20 1.55 0.16 1.24 0.82 1.11 0.50

K2O 2.29 0.16 1.80 0.13 1.79 0.32 2.15 0.10 1.31 1.11 4.10 0.70

P2O5 0.07 0.015 0.09 0.01 0.09 0.01 0.09 0.02 0.06 0.02 0.11 0.11

Total 95.44 2.3 93.97 2.14 89.96 4.08 90.35 2.22 92.39 1.35 93.54 1.17

CIA 58 4 51 3 52 5 58 3 52 13 63 7

n 2 8 9 4 4 5

456


MASLOV

10

1

0.1

(a)

10

1

0.1

(c)


(b)

(d)


Robert Massif

Dry Valley

Fig. 11. PAAS�normalized patterns of the major oxide contents in the glaciogenic and associated rocks of the Sirius Group. (a)Mount Sirius and Robert Massif area; (b) Bennett Platform area; (c) Dominion Range;, (d) Reedy Glacier and Dry Valley area.

ing the presence of a significant fraction of redepositedclastic material related to the erosion of fine�grainedsedimentary rocks, weathered rocks, and soils. Suchdiamictites are located in the highest (above 2000 m)areas of the Transantarctic Mountains. The CIA val�ues in the glacial clays and diamictites located at rela�tively low erosion surfaces (1500–1800 m) are typicalof the unweathered rocks of crystalline basement (52–58), suggesting the predominance of glacial material inthem (Passchier, 2004).

The Pagodroma Group regarded as the EasternAntarctic counterpart of the Neogene Sirius Group(Hambrey and McKelvey, 2000a; McKelvey et al.,2001; Passchier and Whitehead, 2006) includes severalsequences of glacial fjord sediments 800 m thick intotal. The group consists of four formations domi�nated by the coarse�grained weakly sorted sands withgravel and diamictites. Their accumulation settingswere presumably close to those of the modern EasternGreenland fjords (Hambrey and McKelvey, 2000b).The Bardin Bluffs Formation is presently the beststudied unit in the Pagodroma Group (Passchier andWhitehead, 2006). According to biostratigraphic data,its sediments have Early Pliocene–Early Pleistoceneage (Whitehead et al., 2004).

Rocks of the Bardin Bluffs Formation overlie theglacially eroded Permian–Triassic rocks (sandstones,siltstones, and coals) of the Amery Group, which showsigns of chemical transformation in some places. TheBardin Bluffs Formation is subdivided into two units

(Fig. 12) (Bardin, 1982). The basal unit (up to 12.5 mthick) is mainly composed of siltstones and sand�stones. The upper part of the formation (60 m thick),which unconformably overlies rocks of the basal unit,is mainly composed of massive or weakly stratifieddiamictites (with subordinate interbeds of sandy clayscontaining scarce pebbles and small boulders—prod�ucts of ice rafting) and gradationally bedded conglom�erates. Fragments in diamictites were derived fromlocal source areas, and their composition not alwayscorresponds to the matrix composition.

Median contents of the major oxides in rocks of theBardin Bluffs Formation calculated using data (Pass�chier and Whitehead, 2006) are summarized in Table 7.The TiO2 and Al2O3 contents in these rocks approxi�mately correspond to their contents in the upper crust(Wedepohl, 1995). Judging from the TiO2 and Al2O3distribution, all clastic material was derived from a sin�gle source. Sandstones are depleted, while mudstonesare somewhat enriched in Al2O3, relative to the base�ment rocks developed in the distribution area of theBardin Bluffs Formation. Therefore, we can concludethat the provenance rocks were subjected to chemicalweathering, while products of their erosion were accu�mulated in mudstones by means of hydraulic sorting(Young and Nesbitt, 1998).

As compared to the average upper crust (Wedepohl,1995), rocks of the Bardin Bluffs Formation areenriched in SiO2, TiO2, Al2O3, K2O, and depleted inCaO, MgO, and Na2O. Relative to the PAAS, they are



Bardin Bluffs area

Bed

1B

ed 2

1

2

3

Adamson Spur

5 m

Bardin Knollarea

Hiatellaarea

Upper Quike Gully Lower Quike Gully

1 2 3

4 5 6

7 8 9

10

Fig. 12. Proxy sections of exposures of the Bardin Bluffs Formation in the Pagodroma Canyon. Modified after (Passchier andWhitehead, 2006). (1) Massive siltstones with a small amount of rock fragments (products of ice rafting); (2) siltstones with lensesof coarse sandy and gravelly material; (3) siltstones with weakly expressed bedding; (4) siltstones and sandstones with wellexpressed bedding; (5) gradationally bedded conglomerates; (6) diamictites; (7) breccias, (8) closed intervals; (9) unconformity;(10) weathered basement rocks (Permian–Triassic Amery Group).

mostly depleted in CaO (Figs. 13a, 13c, 13d). In thevicinity of the Bardin Bluffs and Adamson Spur, rocksof the Bardin Bluffs Formation are also depleted inFe2O3tot, MgO, and Na2O relative to the PAAS. In theHiatella area, the rocks are fairly close to the PAAS incomposition, but they show significant CaO variations(Fig. 13b). This fact indicates low contents of theinstable phases: plagioclases and Fe–Mg minerals.Moreover, kaolinite is an important constituentamong clay minerals in rocks of the Bardin Bluffs For�mation (Ehrmann et al., 2003; Passchier and White�head, 2006). The CIA value in the Bardin Bluffs rocksvaries within 70–75. This fact also indicates an influxof chemically weathered fine aluminosiliciclastics inthe fjord. These features distinguish the rocks underconsideration from the sediments of modern fjords,the provenances of which were overlain by glaciers.Therefore, the fine�grained sediments accumulatedthere show no signs of chemical weathering (Loringand Asmund, 1996).

The presence of strongly weathered rocks amongglaciogenic deposits was explained by the followingprocesses (Passchier and Whitehead, 2006):(1) rewashing and redeposition of the chemicallyweathered ancient rocks; (2) preglacial and intergla�cial chemical weathering of the basement rocks andsubsequent erosion of the regolith; and (3) postsedi�mentary weathering. At present, the chemical weath�ering in Antarctica is limited by low temperatures and

the absence of a sufficient amount of water in the liq�uid phase. However, some silicate minerals bear signsof alteration even under these conditions (Gibson etal., 1983). High contents of kaolinite in rocks of theBardin Bluffs Formation could be related to erosion inthe underlying sediments (Ehrmann et al., 2003; Junt�tila et al., 2005). Depletion of glacial sediments in Cawas possibly caused by deglaciation, which predatedthe accumulation of sediments of the Bardin BluffsFormation and facilitated exposure of the older prod�ucts of chemical weathering. The last assumption issupported by the presence of 1.5�m�thick weatheringcrust at the base of the Bardin Bluffs Formation (Pass�chier and Whitehead, 2006).

Interesting lithochemical data on the Pleistocenetills of a two�layer aquitard system of the SouthernSaskatchewan (Canada) are reported in (Yan et al.,2000). The upper aquitard consists of the 80�m�thickBattleford till with 35% clay�size fraction (illite is thepredominant mineral). The upper 3 or 4 m of the Bat�tleford till has a brown color and is split by fissures.The underlying rocks are massive and dark�colored(Shaw and Hendry, 1998).

At relatively high median SiO2 and relatively lowAl2O3 contents (~70% and 9.6%, respectively), rocksof the Battleford till are characterized by the medianCIA value of ~42 (Table 7). Relative to the PAAS,rocks of the till are marked by a significantly higher CaOcontent, similar MgO contents, and significantly lower

458


MASLOV

Table 7. Median contents (%) of the major rock�forming oxides and CIA values in the glaciogenic and related rocks of the Bardin BluffsFormation (East Antarctica) and Pleistocene till of Battleford (Saskatchewan, Canada)

Compo�nents

Hiatella area Upper Quike Gully Bardin Bluffs area Adamson Spur Battleford till

Md SD Md SD Md SD Md SD Md SD

SiO2 53.06 2.61 58.83 0.81 62.79 6.51 59.90 2.14 69.90 0.87

TiO2 0.82 0.12 0.87 0.08 0.82 0.11 0.88 0.08 0.41 0.02

Al2O3 17.07 2.11 16.50 1.89 15.44 2.77 15.06 1.55 9.65 0.22

Fe2O3tot 5.69 0.93 5.33 0.15 3.61 1.95 4.49 0.63 3.20 0.12

MnO 0.05 0.15 0.05 0.01 0.03 0.03 0.05 0.01 0.10 0.01

MgO 1.39 0.20 1.49 0.17 1.05 0.45 1.11 0.21 2.00 0.13

CaO 2.35 1.68 0.46 0.08 0.43 0.48 0.50 0.06 4.70 0.37

Na2O 1.00 0.24 1.21 0.12 0.55 0.10 0.67 0.06 1.25 0.14

K2O 3.73 0.25 3.63 0.33 3.77 0.22 3.87 0.29 2.00 0.07

P2O5 0.14 0.03 0.14 0.02 0.09 0.04 0.11 0.02 0.10 0.02

L.O.I. – – – – – – – – 7.00 0.67

Total 84.73 2.28 88.29 1.77 90.47 4.78 87.25 4.55 100.10 0.22

CIA 69 6 71 1 74 3 75 2 42 1

n 6 3 6 3 14

Note: (–) Data absent.

contents of Al2O3, TiO2, Fe2O3, and K2O (Fig. 13d). Thisreflects fairly high contents of quartz and carbonatematerial in the till rocks, and, correspondingly, rela�tively small fraction of Fe–Mg minerals (amphibole,biotite, and chlorite).

CONCLUSIONS

According to the aforementioned data, both thePrecambrian (Maslov, 2010) and younger glaciogenicrocks, as well as related sediments, are characterizedby a fairly wide spectrum of CIA values and diversechemical composition. For instance, diamictites ofthe Ordovician Pakhuis Formation have CIA = 51 ±14, while diamictites of the Upper Paleozoic ItararéGroup have CIA = 60 ± 1. However, the diamictitesare also characterized by another even more remark�able feature: the CIA value in glaciogenic rocks of theDwyka Group varies not only in different basins, butalso in different parts of the same basin. In particular,this index is approximately 70 in the Warmbad Basin,62 in the central Karoo Basin, and as low as ~54 in theeastern part of this structure.

As compared to the PAAS, diamictites of thePakhuis Formation are significantly enriched in CaOand depleted in Na2O. Diamictites of the DwykaGroup in the Karoo Basin are also significantlyenriched in CaO relative to the PAAS. However,unlike the Pakhuis diamictites, they are relativelyenriched in Na2O. Significant depletion in CaO (rela�tive to the PAAS) is the most distinctive feature of theDwyka diamictites in the Warmbad Basin. This featureis typical of diamictites of the Itararé Group in theParaná Basin. In addition, diamictites of the ItararéGroup are significantly depleted in MgO and FeO.

The post�Eocene glacial sediments of Antarcticashow lesser differences in the chemical compositionand lower CIA values. For instance, rocks of the Polo�nez Cove, Magda Nunatak, Hobbs Glacier, and Cock�burn Island formations have CIA values within 55�63.They are steadily enriched in CaO and Na2O, but oftendepleted in K2O relative to the PAAS. Rocks of theSirius Group are also characterized by relatively smallCIA values (51–63). In addition, they are consider�ably depleted in CaO and slightly depleted in K2O. Atthe same time, the glaciogenic sediments of the Pago�droma Group are significantly depleted in CaO in



most cases. The Na2O content in them is somewhatlower than in the PAAS. In terms of the chemicalcomposition, rocks of the Pleistocene Battleford tillare fairly close to the post�Eocene rocks of the Antarc�tic Peninsula. The median CIA value in them (42 ± 1)is the minimal one among all glaciogenic sediments ofdifferent ages analyzed in our work.

The fine�grained terrigenous rocks overlying diam�ictites have significantly higher CIA values (from 67 to76–78), but the CaO and Na2O contents are lowerthan in the PASS. In terms of these characteristics,they are close to the fine�grained rocks formed underhumid or similar climatic conditions. In the Ripheanstratotype section of the South Urals, these rocks arerepresented by the low�carbonaceous shales of theBurzyanian Bakal Formation, as well as by shalesintercalated with carbonate rocks and glauconite�bearing sandstones and siltstones of the Avzyan andInzer formations (Maslov et al., 2004a, 2004b, 2007c).Similar climatic settings were likely responsible for theformation of rocks in the upper part of the Upper Ven�dian section of the Belomorian–Kuloi Plateau(Grazhdankin et al., 2005), low�carbonaceous shalesof the Silurian Bezgodov Formation in the MiddleUrals, and the Middle Jurassic Tyumen carbonaceousformation of the Shaim petroliferous field in WestSiberia (Maslov and Alekseev, 2007; Maslov et al.,2007a, 2007b; Fedorov et al., 2007). In shales and

mudstones of the majority of objects mentioned above,CIA varies from 68 to 77. Except fine�grained rocks ofthe Yurmatinian Avzyan Formation, the rocks are gen�erally characterized by striking depletion in CaO rela�tive to the PAAS (Fig. 14). In addition, rocks of theBakal, Avzyan, and Tyumen formations are signifi�cantly depleted in Na2O (Table 8).

Thus, given that the post�Eocene sediments of theAntarctic Peninsula, rocks of the Sirius Group, andthe Pleistocene Battleford till represent the standard ofglaciogenic rocks, they are characterized, in additionto fairly low CIA values, by significant enrichment inCaO and Na2O, as well as depletion in K2O (relative toPAAS). Among pre�Cenozoic glaciogenic rocks,diamictites of the Port Askaig Formation (CIA = 70 ±5) have a higher CaO content relative to the PAAS, butsignificant relative depletion in Na2O content is absent.In diamictites of the Ayn Formation (CIA = 54 ± 2), theNa2O content is significantly higher than in the PAAS,whereas the CaO content shows insignificant increase.All other diamictites of different ages are characterizedby high CIA values and wide range of the bulk chemi�cal composition, which is presumably caused by dif�ferent local factors, including the presence of redepos�ited sedimentary material.

All aforementioned data allow us to regard the CIAindex as an additional (though very important tool) fordifferent paleoclimatic reconstructions. Some authors

10

1

0.1

(а)

10

1

0.1

(c)


(b)

(d)


Lower Quike Gully

Battleford till

Bardin Knoll

Fig. 13. PAAS�normalized patterns of the major oxide contents in the glaciogenic and related rocks of the Pagodroma Group.(a) Bardin Bluffs area; (b) Hiatella area; (c) Upper Quike Gully and Lower Quike Gully; (d) Adamson Spur, Bardin Knoll, andBattleford till.

460


MASLOV

10

1

0.1

(c)

10

1

0.1

(e)


(d)

(f)


10

1

0.1

(а) (b)

Fig. 14. PAAS�normalized patterns of the major oxide contents in the fine�grained rocks of different ages. (a) Lower RipheanBakal Formation, South Urals; (b) Middle Riphean Avzyan Formation, South Urals; (c) Upper Riphean Inzer Formation, SouthUrals; (d) Lyamitsa, Verkhov, Zimnegorsk, and Erga formations of the Upper Vendian Valdai Group, Belomorian–Kuloi Plateau;(e) Silurian Bezgodov Formation, Middle Urals; (f) Middle Jurassic Tyumen Formation, western Siberian megabasin.

also believe that elevated (relative to both modern andArchean upper continental crust) Fe and lowered Cacontents in the Paleoproterozoic glaciogenic fine�grained rocks of the Gowganda Formation indicatethe low content of free oxygen in atmosphere of thattime and more intense (owing to the higher CO2 con�tents) weathering processes (Kasting, 1987, 1993;Young, 1991, 2001). However, the absence of signifi�cant enrichment in Fe2O3tot content (relative to thePAAS) in diamictites of the Late Archean CoronationFormation requires a careful consideration of theseconcepts.

Data presented in this and previous communica�tion indicate that there are no grounds for suggestingthat the amount of redeposited sedimentary materialin glaciogenic rocks increases with time, because the

CIA value in each specific case is governed mainly bylocal factors (protolith composition, degree of itstransformation by chemical weathering, and others).Only in some sequences of the Paleoproterozoic,Upper Paleozoic, and Cenozoic, the CIA variationsagree well with geological and paleoclimatic data.

ACKNOWLEDGMENTS

The author is grateful to N.S. Glushkova for draw�ing the figures, as well as to D.V. Grazhdankin andV.N. Podkovyrov who helped in collecting therequired literature.

The studies were supported by the Russian Foun�dation for Basic Research (project nos. 09�05�00279



and 07�05�00455) and the Presidium of the RussianAcademy of Sciences (Program No. 15).

REFERENCES

Bangert, B., Stollhofen, H., Lorenz, V., and Armstrong, R.,The Geochronology and Significance of Ash�Fall Tuffs inthe Glaciogenic Carboniferous–Permian Dwyka Group ofNamibia and South Africa, J. Afr. Earth Sci., 1999, vol. 29,pp. 33–49.Bardin, V.I., Composition of East Antarctic Moraines andSome Problems of Cenozoic History,, Third Symposium onAntarctic Geology and Geophysics, Craddock, C., Ed.,Madison: The University of Wisconsin Press, 1982,pp. 1069–1076.Birkenmajer, K., Cenozoic Glacial History of the SouthShetland Islands and Northern Antarctic Peninsula, in Geo�logia de la Antartida Occidental, Lopez�Martinez, J., Ed.,Salamanca, 1992, pp. 251–260.Brady, H. and McKelvey, B., Some Aspects of the CenozoicGlaciation of Southern Victoria Land, Antarctica, J. Glaci�ology, 1983, vol. 29, pp. 343–349.Breza, J.R. and Wise, S.W., Lower Oligocene Ice�RaftedDebris on the Kerguelen Plateau: Evidence for East Antarc�tic Continental Glaciation, Proc. ODP. Sci. Results, CollegeStation, 1992, vol. 120, pp. 161–178.Catuneanu, O., Hancox, P.J., and Rubidge, B.S., Recipro�cal Flexural Behaviour and Contrasting Stratigraphies: ANew Basin Development Model for the Karoo RetroarcForeland System, South Africa, Basin Res., 1998, vol. 10,pp. 417–439.Chumakov, N.M., Klimat i klimaticheskaya zonal’nost’permi i rannego triasa, in Klimat v epokhi krupnykh biosfernykhperestroek, Semikhatov, M.A. and Chumakov, N.M., Eds.,Moscow: Nauka, 2004.Chumakov, N.M., Lednikovyi i bezlednikovyi klimat vdokembrii, in Klimat v epokhi krupnykh biosfernykh pere�

stroek,Semikhatov, M.A. and Chumakov, N.M., Eds., Mos�cow: Nauka, 2004.

Cole, D.I., Evolution and Development of the KarooBasin, in Inversion Tectonics of the Cape Fold Belt, Karooand Cretaceous Basins of Southern Africa, De Wit, M.J.and Ransome, I.G.D., Eds., 1992, pp. 87–99.

Dingle R.V. and Lavelle M., Late Cretaceous�CenozoicClimatic Variations of the Northern Antarctic Peninsula:New Geochemical Evidence and Review, Palaeogeogr.,Palaeoclimat., Palaeoecol., 1998, vol. 141, pp. 215–232.

Dingle, R.V., McArthur, J.M., and Vroon P., Oligocene andPliocene Interglacial Events in the Antarctic PeninsulaDated Using Strontium Isotope Stratigraphy, J. Geol. Soc.,1997, vol. 154, pp. 257–264.

Earth’S Pre�Pleistocene Glacial Record, Hambrey, M.J.,Harland, W.B., Chumakov, N.M., et al., Eds., Cambridge:Cambridge Univ. Press, 1981, p. 1004.

Ehrmann, W.U., Implications of Sediment Composition onthe Southern Kerguelen Plateau for Paleoclimate and Dep�ositional Environment, Proc. ODP. Sci. Results, 1991,vol. 119, pp. 185–203.

Ehrmann, W.U. and Mackensen, A., SedimentologicalEvidence for the Formation of an East Antarctic Ice Sheetin Eocene/Oligocene Time, Palaeogeogr. Palaeoclimat.Palaeoecol., 1992, vol. 93, pp. 85–112.

Ehrmann, W., Bloemendal, J., Hambrey, M., et al., Varia�tions in the Composition of the Clay Fraction of the Ceno�zoic Pagodroma Group, East Antarctica: implications fordetermining provenance, Sediment. Geol., 2003, vol. 161,pp. 131–152.

Eyles, C.H., Eyles, N., and Franca, A.B., Glaciation andTectonics in an Active Intracratonic Basin: The Late Palae�ozoic Itararé Group, Paraná Basin, Brazil, Sedimentology,1993, vol. 40, pp. 1–25.

Fedorov, Yu.N., Maslov, A.V., Alekseev, V.P., et al., Sistem�atika redkozemel’nykh i ryada elementov�primesei v

Table 8. PAAS�normalized median contents (%) of some rock�forming oxides in different lithostratigraphic units of the Riphean,Vendian, Paleozoic, and Mesozoic

Components Al2O3 Fe2O3 MgO CaO Na2O K2O P2O5

South Urals, Bakal Formation (Lower Riphean)

Southern Urals, Avzyan For�mation (Middle Riphean)

South Urals, Inzer Formation (Upper Riphean)

Belomorian–Kuloi Plateau, Zimnegorsk and Erga forma�tions (Upper Vendian)

Middle Urals, Bezgodov Formation (Silurian)

Western Siberia, Tyumen Formation (Middle Jurassic)

Note: Variation range is shown in the nominator; median value, in the denominator.

0.68 1.15–1.03

�� 0.73 2.15–1.21

�� 0.41 1.33–0.74

�� 0.05 3.11–0.20

�� 0.08 1.80–0.48

�� 0.58 1.63–1.08

�� 0.26 1.88–0.53

��

0.74 1.09–0.94

�� 0.46 1.27–0.94

�� 0.57 4.03–1.45

�� 0.23 6.40–1.08

�� 0.09 0.99–0.49

�� 0.74 2.07–1.54

�� 0.06 1.00–0.38

��

0.65 1.20–0.97

�� 0.26 1.41–0.95

�� 0.55 1.53–0.99

�� 0.21 1.95–0.53

�� 0.09 1.18–0.89

�� 0.07 2.12–1.33

�� 0.13 1.44–0.63

��

0.54 1.07–0.91

�� 0.45 1.92–1.31

�� 0.30 1.68–1.25

�� 0.12 0.76–0.32

�� 0.11 2.14–1.07

�� 0.95 1.40–1.12

�� 0.13 1.75–0.69

��

0.35 0.97–0.90

�� 0.80 1.58–1.23

�� 0.67 0.97–0.89

�� 0.13 3.86–0.22

�� 0.42 1.71–1.14

�� 0.26 1.29–1.04

�� 0.35 12.88–0.49

��

0.44 1.21–0.89

�� 0.12 1.42–0.36

�� 0.33 1.26–0.82

�� 0.08 2.08–0.28

�� 0.17 1.57–0.61

�� 0.23 1.29–0.58

�� 0.06 13.88–0.75

��

462


MASLOV

porodakh yury Severo�Pokachevskogo mestorozhdeniya (Shi�rotnoe Priob’e), Gornye Vedomosti, 2007, no. 12, pp. 24–37.Geiger, M., The Geology of the Southern Warmbad BasinMargin – Tephrostratigraphy, Age, Fossil Record and Sed�imentary Environment of Carboniferous�Permian Gla�cigenic Deposits of the Dwyka Group, Zwartbas, SouthernNamibia, Würzburg: Julius�Maximilians�Universitát,2000.Gibson, E.K., Wentworth, S.J., and McKay, D.S., Chemi�cal Weathering and Diagenesis of a Cold Desert Soil fromWright Valley, Antarctica: An anolog of Martian WeatheringProcesses, J. Geophys. Res., 1983, vol. 88 (Suppl.),pp. A912–A928.Grazhdankin, D.V., Podkovyrov, V.N., and Maslov, A.V.,Paleoclimatic Settings of the Formation of Upper VendianRocks on the Belomorian–Kuloi Plateau (SoutheasternWhite Sea Region), Litol. Polezn. Iskop., 2005, no. 3,pp. 267–280 [Lithol. Miner. Resour. (Engl. Transl.), 2005,no. 3, pp. 232–244].Hambrey, M.J., Barrett, P.J., Cenozoic Sedimentary andClimatic Record from the Ross Sea Region, Antarctica, inThe Antarctic Paleoenvironment: A Perspective on GlobalChange, Kennett, J.P. and Warnke, D.A, Eds., Washington,DC: Am. Geophys. Union, 1993, part 2.Hambrey, M.J. and McKelvey, B., Major Neogene Fluctu�ations of the East Antarctic Ice Sheet: Stratigraphic Evi�dence from the Lambert Glacier Region, Geology, 2000a,vol. 28, pp. 865–960.Hambrey, M.J. and McKelvey, B., Neogene Fjordal Sedi�mentation on the Western Margin of the Lambert Graben,East Antarctica, Sedimentology, 2000b, vol. 47, pp. 577–608.Huber, H., Koeberl, C., McDonald, I., and Reimold, W.U.,Geochemistry and Petrology of Witwatersrand and Dwykadiamictites from South Africa: Search for an ExtraterrestrialComponent, Geochim. Cosmochim. Acta, 2001, vol. 65, pp.2007–2016.Jonkers, H.A., Lirio, J.M., Del Valle, R.A., and Kelley, S.P.,Age and Environment of Miocene–Pliocene GlaciomarineDeposits, James Ross Island, Antarctica, Geol. Mag., 2002,vol. 139.Junttila, J., Ruikka, M., and Strand, K., Clay�MineralAssemblages in High�Resolution Plio�Pleistocene Intervalat ODP Site 1165, Prydz Bay, Antarctica, Global Planet.Change, 2005, vol. 45, pp. 151–163.Kasting, J.F., Theoretical Constraints on Oxygen and Car�bon Dioxide Concentrations in the Precambrian Atmo�sphere, Precambr. Res., 1987, vol. 34, pp. 205–229.Kasting, J.F. Earth’s Early Atmosphere, Science, 1993,vol. 259, pp. 920–926.Kennett, J.P., Cenozoic Evolution of Antarctic Glaciation,the Circum�Antarctic Ocean, and Their Impact on GlobalPaleoceanography, J. Geophys. Res., 1977, vol. 82,pp. 3843–3860.Loring, D.H. and Asmund, G., Geochemical Factors Con�trolling Accumulation of Major and Trace Elements inGreenland Coastal and Fjord Sediments, Environ. Geol.,1996, vol. 28, pp. 2–11.Marchant, J.W. and Moore, A.E., Geochemistry of theTable Mountain Group: II. Analysis of Two Suites of West�ern Graafwater Rocks, Trans. Geol. Soc. S. Afr., 1978,vol. 81, pp. 353–359.

Maslov, A.V., Glaciogenic and Associated SedimentaryRocks: Main Features of Lithochemistry. Communication1. Late Archean and Proterozoic, Litol. Polezn. Iskop.,2010, no. 4, pp. 355–370 [Lithol. Miner. Resour. (Engl.Transl.), 2010, no. 4, pp. 333–346].Maslov, A.V. and Alekseev, V.P., Specific Features of theChemical Composition and REE–Th–Sc Systematics ofthe Lower Mesozoic Fine�Grained Terrigenous Rocks inthe Shaim Petroliferous Region (West Siberia), Izv. Vyssh.Uchebn. Zaved., Geol. Razved., 2007, no. 2, pp. 21–30.Maslov, A.V., Ronkin, Yu.L., Krupenin, M.T., et al., LowerRiphean Fine�Grained Alumosiliciclastic SedimentaryRocks of the Bashkirian Anticlinorium in the SouthernUrals: Composition and Evolution of Provenances,Geokhimiya, 2004a, no. 6, pp. 648–669 [Geochem. Int.(Engl. Transl.), 2004a, no. 6, pp. 635–654].Maslov, A.V., Krupenin, M.T., Ronkin, Yu.L., et al., Fine�Grained Aluminosiliciclastic Rocks of the Middle RipheanStratotype Section in the Middle Urals: Peculiarities of theFormation, Composition, and Evolution of Source Rocks,Litol. Polezn. Iskop., 2004b, no. 4, pp. 414–441 [Lithol.Miner. Resour. (Engl. Transl.), 2004b, no. 4, pp. 357–320].Maslov, A.V., Alekseev, V.P., and Fedorov, Yu.N., Verifica�tion of Genetic Reconstructions Based on LithochemicalIndicators for the Tyumen Fomeation of the ShaimPetroliferous Region, in Puti Realizatsii Neftegazovogo iRudnogo Potentsiala Khanty�Mansiiskogo AvtonomnogoOkruga�Yugry (Pathways for the Realization of Petroleumand Ore Potential of the Khanty�Mansi Autonomous YugraRegion), 2007a, vol. 1, pp. 246–253..Maslov, A.V., Alekseev, V.P., Fedorov, Yu.N., and Ronkin, Yu.L.,The REE Systematics of the Lower Mesozoic Fine�Grained Terrigenous Rocks in the Shaim PetroliferousRegion, in Sostoyanie, Tendentsii I Problemy RazvitiyaNeftegazovogo Potentsiala Zapadnoi Sibiri (State, Trend,and Problems of the Development of Petroleum Potentialin West Siberia), Tyumen: FGUP ZapSibNIIGG, 2007b,pp. 379–384.Maslov, A.V., Gareev, E.Z., Krupenin, M.T., and Ronkin, Yu.L.,Lithogeochemical Features of the Upper Riphean Shalesand Mudstones in the Bashkirian Anticlinorium in theReal�Time Coordinates, Litosfera, 2007c, no. 5, pp. 38–67.Mayewski, P.A. and Goldthwait, R.P., Glacial Events in theTransantarctic Mountains: A Record of the East AntarcticIce Sheet, Am. Geophys. Union. Antarct. Res. Ser., 1985,vol. 36, pp. 275–324.McKelvey, B.C., Webb, P.�N., Harwood, D.M., andMabin, M.G.C., The Dominion Range Sirius Group: ARecord of the Late Pliocene�Early Pleistocene BeardmoreGlacier, in Fifth International Symposium on Antarctic Earth Sci�ences, Thomson, M.R.A., Crame, J.A., and Thomson, J.W.,Eds., Cambridge: Cambr. Univ. Press, 1991.McKelvey, B.C., Harwood, M.J., Harwood, D.M., et al.,The Pagodroma Group – A Cenozoic Record of the EastAntarctic Ice Sheet in the Northern Prince Charles Moun�tains, Antarct. Sci., 2001, vol. 13, pp. 455–468.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.Passchier, S., Provenance and Depositional Environmentsof Neogene Sirius Group Deposits from the Shackleton andBeardmore Glacier Areas, Central Transantarctic Moun�tains, in Antarctica at the Close of a Millennium, Gamble, J.A.,



Skinner, D.N.B., and Henrys, S., Eds., R. Soc. New Zeal.Bull., 2002, vol. 35, pp. 309–318.

Passchier, S., Variability in Geochemical Provenance andWeathering History of Sirius Group Strata, TransantarcticMountains: Implications for Antarctic Glacial History,J. Sediment. Res., 2004, vol. 74, pp. 607–619.

Passchier, S. and Krissek, L.A., Oligocene�Miocene Ant�arctic Continental Weathering Record and PaleoclimaticImplications, Cape Roberts Drilling Project, Ross Sea,Antarctica, Palaeogeogr. Palaeoclimat. Palaeoecol, 2008.

Passchier, S. and Whitehead, J.M., Anomalous Geochemi�cal Provenance and Weathering History of Plio�PleistoceneGlaciomarine Fjord Strata, Bardin Bluffs Formation, EastAntarctica, Sedimentology, 2006, vol. 53, pp. 929–942.

Reimold, W. U., von Brunn, V., and Koeberl, C., AreDiamictites Impact Ejecta? No supporting Evidence fromSouth African Dwyka Group Diamictite, J. Geol., 1997, vol.105, pp. 517–530.

Robert, C. and Chamley, H., Late Eocene�Early OligoceneEvolution of Climate and Marine Circulation: Deep�SeaClay Mineral Evidence, in The Antarctic Paleoenvironment: APerspective on Global Change, Kennett, J.P. and Warnke, D.A,Eds., Washington, DC: Am. Geophys. Union, 1992, Part 1.

Rust I.C. Lower Palaeozoic Rocks of Southen Africa, inLower Palaeozoic of the Middle East, Eastern and SouthernAfrica and Antarctica, Holland, C.H., Ed., Chichester: JohnWiley and Sons, 1981.

Scheffler, K., Reconstruction of Sedimentary Environmentand Climate Conditions by Multi�Geochemical Investiga�tions of Late Palaeozoic Glacial to Postglacial SedimentarySequences from SW�Gondwana, Dissertation zur Erlan�gung des Doktorgrades, Bonn: Rheinischen Friedrich�Wil�helms�Universitát, 2004, 243 p.

Scheffler, K., Hoernes, S., and Schwark, L., GlobalChanges during Carboniferous�Permian Glaciation ofGondwana: Linking Polar and Equatorial Climate Evolu�tion by Geochemical Proxies, Geology, 2003, vol. 31,pp. 605–608.

Scheffler, K., Buehmann, D., and Schwark, L., Analysis ofLate Palaeozoic Glacial to Postglacial Sedimentary Succes�sions in South Africa by Geochemical Proxies � Responseto Climate Evolution and Sedimentary Environment,Palaeogeogr. Palaeoclimat. Palaeoecol., 2006, vol. 240,pp. 184–203.

Shaw, R.J. and Hendry, M.J., Hydrogeology of a Thick ClayTill and Cretaceous Clay Sequence, Saskatchewan, Can�ada, Can. Geotech. J., 1998, vol. 35, pp. 1–12.

Smith, R.M.H., Eriksson, P.G., and Botha, W.J. A Reviewof the Stratigraphy and Sedimentary Environments of theKaroo�Aged Basins of Southern Africa, J. Afr. Earth Sci.,1993, vol. 16.

Stollhofen, H., Stanistreet, I.G., Bangert, B., and Grill, H.,Tuffs, Tectonism and Glacially Related Sea Level Changes,Carboniferous–Permian, Southern Namibia, Palaeogeogr.Palaeoclimat. Palaeoecol., 2000, vol. 161, pp. 127–150.

Stroeven, A.P. and Prentice, M., L., A Case for SiriusGroup Alpine Glaciation at Mount Fleming, South Victo�ria Land, Antarctica: A Case against Pliocene East Antarc�tic Ice Sheet Reduction, Geol. Soc. Am. Bull., 1997.

Taylor, S.R. and McLennan, S.M., The Continental Crust:Its Composition and Evolution, Oxford: Blackwell 1985.

Translated under the title Kontinental’naya kora: ee sostav ievolyutsiya, Moscow: Mir, 1988.Troedson, A.L. and Riding, J.B., Upper Oligocene to Low�ermost Miocene Strata of King George Island, South Shet�land Islands, Antarctica: Stratigraphy, Facies Analysis, andImplications for the Glacial History of the Antarctic Penin�sula, J. Sediment. Res., 2002.Turner, B.R., Tectonostratigraphical Development of theUpper Karoo Foreland Basin: Orogenic Unloading versusThermally�Induced Gondwana Rifting, J. Afr. Earth Sci.,1999, vol. 28, pp. 215–238.Visser, J.N.J., The Table Mountain Group: A Study in theDeposition of Quartz Arenites on a Stable Shelf, Trans.Geol. Soc. S. Afr., 1974, vol. 77, pp. 229–237.Visser, J.N.J., The Permo�Carboniferous Dwyka Forma�tion of Southern Africa. Deposition by a PredominantlySubpolar Marine Ice Sheet, Palaeogeogr. Palaeoclimat.Palaeoecol., 1989, vol. 70, pp. 377–391.Visser, J.N.J., Post�Glacial Permian Stratigraphy andGeography of Southern and Central Africa. Boundary Con�ditions for Climatic Modeling, Palaeogeogr. Palaeoclimat.Palaeoecol., 1995, vol. 118, pp. 213–243.Visser, J.N.J., Deglaciation Sequences in the Permo�Car�boniferous Karoo and Kalahari Basins of Southern Africa.A Tool in the Analysis of Cyclic Glaciomarine Basin Fills,Sedimentology, 1997, vol. 44, pp. 507–521.Visser, J.N.J. and Young, G.M., Major Element Geochem�istry and Paleoclimatology of the Permo�CarboniferousGlacigene Dwyka Formation and Post�Glacial Mudrocksin Southern Africa, Palaeogeogr. Palaeoclimat. Palaeoecol.,1990, vol. 81, pp. 49–57.Webb, P.�N., Harwood, D.M., Mabin, M.G.C., andMcKelvey B.C., A Marine and Terrestrial Sirius GroupSuccession, Middle Beardmore Glacier–Queen AlexandraRange, Transantarctic Mountains, Antarctica, Mar. Micro�paleont., 1996a, vol. 27, pp. 273–297.Webb, P.�N., Harwood, D.M., Hambrey, M.J., et al., TheLate Cenozoic Sirius Group of the Upper Shackleton Gla�cier Region, Transantarctic Mountains, Antarctic J. UnitedStates, 1996b, vol. 31, pp. 12–13.Wedepohl, K.H., The Composition of the ContinentalCrust, Geochim. Cosmochim. Acta, 1995, vol. 59, pp, 1217–1232.Whitehead, J.M., Harwood, D.M., McKelvey, B.C., et al.,Diatom Biostratigraphy of the Cenozoic Fjordal Pago�droma Group, Northern Prince Charles Mountains, EastAntarctica, Aust. J. Earth Sci., 2004, vol. 51, pp. 521–547.Wilson, G.S., Barron, J.A., Harwood, D.M., et al., TheMount Feather Diamicton of the Sirius Group: An Accu�mulation of Indicators of Neogene Antarctic Glacial andClimatic History, Palaeogeogr. Palaeoclimat. Palaeoecol.,2002, vol. 182, pp. 117–131.Yan, X.�P., Kerrich, R., and Hendry, M.J., Trace ElementGeochemistry of a Thick Till and Clay�Rich AquitardSequence, Saskatchewan, Canada, Chem. Geol., 2000,vol. 164, pp. 93–120.Young, G.M., The Geologic Record of Glaciation: Rele�vance to the Climatic History of Earth, Geosci. Can., 1991,vol. 18, pp. 100–108.Young, G.M., Comparative Geochemistry of Pleistoceneand Paleoproterozoic (Huronian) Glaciogenic LaminatedDeposits: Relevance to Crustal and Atmospheric Composi�

464


MASLOV

tion in the Last 2.3 Ga, J. Geol., 2001, vol. 109, pp. 463–477.

Young, G.M. and Nesbitt, H.W., Processes Controlling theDistribution of Ti and Al in Weathering Profiles, Siliciclas�tic Sediments and Sedimentary Rocks, J. Sediment. Res.,1998, vol. 68.

Young, G.M., Minter, W.E.,L., and Theron, J.N.,Geochemistry and Palaeogeography of Upper OrdovicianGlaciogenic Sedimentary Rocks in the Table MountainGroup, South Africa, Palaeogeogr. Palaeoclimat. Palaeo�ecol., 2004, pp. 323–345.

Zachos, J., Pagani, M., and Sloan, L., et al., Trends,Rhythms, and Aberrations in Global Climate 65 Ma toPresent, Science, 2001.Zalán, P.V., Wolff, S., Conceicao, J.C.J., et al., The ParanáBasin, Brazil,, in Interior Cratonic Basins, Leighton, M.W.,Kolata, D.R., and Oltz, D.F., Eds., Am. Assoc. Petrol. Geol.,1990, vol. 51, pp. 681–708.Zharkov, M.A., Paleogeographic Rearrangements and Set�tings of Sedimentation in the Permian and Early Triassic, inKlimat v epokhi krupnykh biosfernykh perestroek (Climateduring Epochs of Great Biospheric Rearrangements),Semikhatov, M.A. and Chumakov, N.M., Eds., Moscow:Nauka, 2004.

Glaciogenic and Related Sedimentary Rocks: Main Lithochemical Features. Communication 2. The...

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