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Clay mineralogy across the P-T boundary of the Xiakou section, China: Evidence of clay provenance and environment

Published online by Cambridge University Press:  01 January 2024

Hanlie Hong*
Affiliation:
Faculty of Earth Sciences, China University of Geosciences, Wuhan Hubei, 430074, P.R. China
Ning Zhang
Affiliation:
Faculty of Earth Sciences, China University of Geosciences, Wuhan Hubei, 430074, P.R. China
Li Zhaohui
Affiliation:
Geosciences Department, University of Wisconsin - Parkside, Kenosha, WI 53141-2000, USA Department of Earth Sciences, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan
Huijuang Xue
Affiliation:
Faculty of Earth Sciences, China University of Geosciences, Wuhan Hubei, 430074, P.R. China
Wenchen Xia
Affiliation:
Faculty of Earth Sciences, China University of Geosciences, Wuhan Hubei, 430074, P.R. China
Na Yu
Affiliation:
Faculty of Earth Sciences, China University of Geosciences, Wuhan Hubei, 430074, P.R. China
*
* E-mail address of corresponding author: honghl8311@yahoo.com.cn
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Abstract

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The provenance of clays in shaley intervals across the Permian-Triassic boundary (PTB) in the Xiakou section was investigated by X-ray diffraction (XRD), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM), and the results suggest that the layers have three different provenances. The layer P267-b has a loose texture with an oriented arrangement of detrital clay particles, consisting mainly of illite and minor chlorite with irregular outlines or ragged edges. The dehydroxylation reaction of the clays in this layer is characterized by an intense overlapping endothermic effect at ∼600°C, produced by mixed-layer illite-smectite (I-S) consisting of a mixture of cis-vacant (cv)and trans-vacant (tv) octahedral sheets derived from weathering of detrital illite. Layer P259-b shows a more condensed texture with a dark color, and is composed mainly of I-S and minor illite and chlorite. Evidence for alteration of detrital materials to clay mineral aggregates was observed under SEM. Similar to layer P267-b, an intense dehydroxylation reaction occurs at ∼600°C, indicating clays consisting of a mixture of tv and cv sheets and, therefore, that the sediments were derived from a mixture of terrigenous and volcanic sources, combining the texture and the clay-mineral composition of those sediments. However, the undisturbed lamination and relatively small grain size in this bed indicate a low-energy depositional environment. The clay-mineral compositions of the other layers are mainly of I-S with minor amounts of illite and chlorite. Their endothermic dehydroxylation reaction, however, occurs mainly at ∼660°C, indicating that cv sheets are dominant in the clays, and thus, are derived from smectites of volcanic origin. Observations by SEM show that clay minerals grow at the expense of detrital materials, confirming the diagenetic alteration of volcanic ashes in marine sediments. Illite and chlorite are the detrital clay minerals in the clay layers across the PTB in the Xiakou section. The presence of detrital illite and chlorite in the sediments means that an arid climate prevailed in the region during the end-Permian and early Triassic period.

Type
Research Article
Copyright
Copyright © 2008, The Clay Minerals Society

References

Adatte, T. and Keller, G., 1998 Increased volcanism, sea-level and climatic fluctuations through the K/T boundary: mineralogical and geochemical evidences Abstract, International Seminar on Recent Advances in the Study of Cretaceous Sections Chennai, India Oil and Natural Gas Corporation Limited, Regional Geoscience Laboratory 2.Google Scholar
Chamley, H., 1989 Clay Sedimentology Berlin Springer Verlag 623 pp.CrossRefGoogle Scholar
Deconinck, J.F. and Chamley, H., 1995 Diversity of smectite origins in late Cretaceous sediments: example of chalks from northern France Clay Minerals 30 365379.CrossRefGoogle Scholar
Drits, V.A. Besson, G. and Muller, E., 1995 An improved model for structural transformation of heat-treated aluminous dioctahedral 2:1 layer silicates. Clays and Clay Minerals 43 718731.CrossRefGoogle Scholar
Drits, V.A. Lindgreen, H. Salyn, A.L. Ylagan, R. and McCarty, D.K., 1998 Semiquantitative determination of trans-vacant and cis-vacant 2:1 layers in illites and illite-smectites by thermal analysis and X-ray diffraction American Mineralogist 83 11881198.CrossRefGoogle Scholar
Hallam, A. Grose, J.A. and Ruffell, A.H., 1991 Palaeoclimatic significance of changes in clay mineralogy across the Jurassic-Cretaceous boundary in England and France Palaeogeography, Palaeoclimatology, Palaeoceology 81 173187.CrossRefGoogle Scholar
Hardy, R. Tucker, M. and Tucker, M., 1988 X-ray powder diffraction of sediments Techniques in Sedimentology Oxford, UK Blackwell Science 191228.Google Scholar
Hower, J. Eslinger, E.V. Hower, M.E. and Perry, E.A., 1976 Mechanism of burial metamorphism of argillaceous sediment: 1. Mineralogical and chemical evidence Geological Society of America Bulletin 87 725737.2.0.CO;2>CrossRefGoogle Scholar
Jackson, M.L., 1978 Soil Chemical Analyses Madison, USA Published by the author, University of Wisconsin.Google Scholar
Lindgreen, H. and Surlyk, F., 2000 Upper Permian-Lower Cretaceous clay mineralogy of East Greenland: provenance, palaeoclimate and volcanicity Clay Minerals 35 791806.CrossRefGoogle Scholar
Lu, Q., Lei, X.R., and Liu, H.F. (1990) Genesis types and crystal chemical classification of irregular illite/smectite interstratified clay minerals. The 15th International Mineral Meeting, Beijing.Google Scholar
Lu, Q. Lei, X.R. and Liu, H.F., 1991 Genetic types and crystal chemical classification of irregular illite/smectite interstratified clay minerals Acta Mineralogica Sinica 11 97104 (in Chinese with English abstract).Google Scholar
Lu, Q. Lei, X.R. and Liu, H.F., 1993 Study of the stacking sequences of a kind of irregular mixed-layer illite-smectite (I/S) clay mineral Acta Geologica Sinica 67 123130 (in Chinese with English abstract).Google Scholar
Madhavaraju, J. Ramasamy, S. Ruffell, A. and Mohan, S.P., 2002 Clay mineralogy of the late Cretaceous and early Tertiary successions of the Cauvery Basin (southeastern India): implications for sediment source and palaeoclimates at the K/T boundary Cretaceous Research 23 153163.CrossRefGoogle Scholar
Millot, G., 1970 Geology of Clays Berlin Springer-Verlag 499 pp.CrossRefGoogle Scholar
Moore, D.M. and Reynolds, R.C., 1989 X-ray Diffraction and the Identification and Analysis of Clay Minerals New York Oxford University Press 332 pp.Google Scholar
Nadeau, P.H. and Reynolds, R.C. Jr., 1981 Volcanic components in pelitic sediments Nature 294 7274.CrossRefGoogle Scholar
Pearson, M.J. and Small, J.S., 1988 Illite-smectite diagenesis and palaeotemperatures in northern North Sea Quaternary to Mesozoic shale sequences Clay Minerals 23 109132.CrossRefGoogle Scholar
Perry, E.A. and Hower, J., 1970 Burial diagenesis in Gulf Coast pelitic sediments Clays and Clay Minerals 18 165177.CrossRefGoogle Scholar
Reynolds, R.C. and Hower, J., 1970 The nature of interlayering in mixed-layer illite-montmorillonite Clays and Clay Minerals 18 2536.CrossRefGoogle Scholar
Riedmüller, G., 1978 Neoformations and transformations of clay minerals in tectonic shear zones Tschermaks Mineralogische und Petrographische Mitteilungen 25 219242.CrossRefGoogle Scholar
Robert, C. and Kennett, J.P., 1994 Antarctic subtropical humid episode at the Paleocene-Eocene boundary: Clay-mineral evidence Geology 22 211214.2.3.CO;2>CrossRefGoogle Scholar
Tsipurski, S.I. and Drits, V.A., 1984 The distribution of octahedral cations in the 2:1 layers of dioctahedral smectites studied by oblique-texture electron diffraction Clay Minerals 19 177193.CrossRefGoogle Scholar
Wang, G.Q. and Xia, W.C., 2004 Conodont zonation across the Permian-Triassic boundary at the Xiakou section, Yichang city, Hubei province and its correlation with the Global Stratotype Section and Point of the PTB Canadian Journal of Earth Sciences 41 323330.Google Scholar
Wang, Z.Y., 1998 Permian sedimentary facies and sequence stratigraphy in Daxiakou section, Xingshan county, Hubei province Journal of Jianhan Petroleum Institute 20 3 17.Google Scholar
Weaver, C.E., 1989 Clays, Muds, and Shales Amsterdam Elsevier 819 pp.Google Scholar
Wu, S.B. Ren, Y.X. and Bi, X.M., 1990 Volcanic material and origin of clay rock near Permo-Triassic boundary from Huangshi, Hubei and Meishan of Changxing county, Zhejiang Earth Science-Journal of China University of Geosciences 15 589594.Google Scholar
Yin, H.F. Huang, S.J. Zhang, K.X. Hansen, H.J., Sweet, W.C. Yang, Z.Y. Dickins, J.M. and Yin, H.F., 1992 The effects of volcanism on the Permo-Triassic mass extinction in South China Permo-Triassic Events in the Eastern Tethys Cambridge, UK Cambridge University Press 146157.Google Scholar
Yin, H.F. Zhang, K.X. Tong, J.N. Yang, Z.Y. and Wu, S.B., 2001 The global stratotype section and point (GSSP) of the Permian-Triassic boundary Episodes 24 102113.Google Scholar
Yu, K.P. Han, G.M. Yang, F.L. Mansy, J.L. Xu, C.H. Zhou, Z.Y. Cheng, X.R. Liu, Z.F. and Fu, Q., 2005 Study on clay minerals of P/T boundary in Meishan section, Changxin, Zhejiang province Acta Sedimentologica Sinica 23 108112 (in Chinese with English abstract).Google Scholar
Zhang, S.X. Yu, J.X. Yang, F.Q. Peng, Y.Q. Yin, H.F. and Yu, J.S., 2004 Study on clayrocks of the neritic, littoral and marine-terrigenous facies across the Permian-Triassic boundary in eastern Yunnan and western Guizhou, south China Journal of Mineralogy and Petrology 24 4 8186 (in Chinese with English abstract).Google Scholar