TYPICAL MUDSTONE OF THE LOWER PERMIAN SHOUSHANGOU FORMATION IN MIDDLE-SOUTH DAXINGANLING MOUNTAINS: Geochemical Characteristics and Geological Implications
ZHOU Cheng-lin1, TANG You-jun1, LIU Bin2
1. School of Resources and Environment, Yangtze University, Wuhan 430100, China; 2. School of Earth Sciences, Yangtze University, Wuhan 430100, China
Abstract：The mudstones of Lower Permian Shoushangou Formation in Xi Ujimqin Qi of Inner Mongolia are well-developed source rocks in middle-south Daxinganling Mountains. With study on the characteristics of major, trace and rare earth elements in the mudstones, the paper analyzes the provenance, tectonic setting and weathering of Shoushangou Formation in depth. The ICV values of rock samples ranging from 1.15 to 1.57(averagely 1.33) show that the samples are basically not affected by secondary diagenesis. According to the A-CN-K triangular diagram, the mudstones are subjected to certain K-metasomatism. The CIAcorr values of 54.28-70.06 (averagely 65.33) are gained after correction, indicating the provenance has experienced primary-moderate weathering. Based on the analysis on the multivariable environment of major and trace elements, it is concluded that the argillaceous sediments of Shoushangou Formation are mainly derived from the felsic provenance, mixed with minus materials from the femic volcanic rock provenance, under the tectonic background of continental island arc. From the above, it is thought that the sedimentary features of the mudstones in the study area are attributed to the subduction of the Paleo-Asian Oceanic crust in early Permian.
Wronkiewicz D J, Condie K C. Geochemistry and provenance of sediments from the Pongola Supergroup, South Africa:Evidence for a 3.0-Ga-old continental craton[J]. Geochimica et Cosmochimica Acta, 1989, 53(7):1537-1549.
[8]
Nesbitt H W, Young G M. Early proterozoic climates and plate motions inferred from major element chemistry of lutites[J]. Nature,1982,299:715-717.
[9]
Nesbitt H W, Young G M, McLennan S M, et al. Effects of chemical weathering and sorting on the petrogenesis of siliciclastic sediments, with implications for provenance studies[J]. Journal of Geology,1996, 104(5):525-542.
[10]
Nesbitt H W, Young G M. Petrogenesis of sediments in the absence of chemical weathering:Effects of abrasion and sorting on bulk composition and mineralogy[J]. Sedimentology, 1996,43(2):341-358.
[11]
McLennan S M. Weathering and global denudation[J]. Journal of Geology, 1993,101(2):295-303.
[12]
Cullers R L. The geochemistry of shales, siltstones and sandstones of Pennsylvanian-Permian age, Colorado, USA:Implications for provenance and metamorphic studies[J]. Lithos,2000,51(3):181-203.
Garzanti E, Padoan M, Andò S, et al. Weathering and relative durability of detrital minerals in equatorial climate:Sand petrology and geochemistry in the East African Rift[J]. Journal of Geology, 2013,121(6):547-580.
[23]
Taylor S R, McLennan S M. The continental crust:Its composition and evolution, an examination of the geochemical record preserved in sedimentary rocks[J]. Journal of Geology, 1985,94(4):632-633.
[24]
Bhatia M R. Rare earth element geochemistry of Australian Paleozoic graywackes and mudrocks:Provenance and tectonic control[J]. Sedimentary Geology, 1985,45(1):97-113.
Fedo C M, Nesbitt H W, Young G M. Unraveling the effects of potassium metasomatism in sedimentary rocks and paleosols, with implications for paleoweathering conditions and provenance[J]. Geology, 1995,23(10):921-924.
Cox R, Lowe D R, Cullers R L. The influence of sediment recycling and basement composition on evolution of mudrock chemistry in the southwestern United States[J]. Geochim Cosmochim Acta, 1995,59(14):2919-2940.
[30]
Kamp P C, Leake B E. Petrography and geochemistry of feldspathic and mafic sediments of the northeastern Pacific margin[J]. Transactions of the Royal Society of Edinburgh Earth Sciences, 1985,76(4):411-449.
[31]
Nesbitt H W, Young G M. Prediction of some weathering trends of plutonic and volcanic rocks based on thermodynamic and kinetic considerations[J]. Geochimica et Cosmochimica Acta, 1984,48(7):1523-1534.
[32]
Nesbitt H W, Young G M. Formation and diagenesis of weathering Profiles[J]. Journal of Geology, 1989,97(2):129-147.
[33]
Panahi A, Young G M, Rainbird R H. Behavior of major and trace elements (including REE) during Paleoproterozoic pedogenesis and diagenetic alteration of an Archean granite near Ville Marie, Québec, Canada[J]. Geochimica et Cosmochimica Acta, 2000,64(13):2199-2220.
Roser B P, Korsch R J. Provenance signatures of sandstone-mudstone suites determined using discriminant function analysis of major-element data[J]. Chemical Geology, 1988,67(1):119-139.
Girty G H, Ridge D L, Knaack C. Provenance and depositional setting of Paleozoic chert and argillite, Sierra Nevada, California[J]. Journal of Sedimentary Research, 1996,66(1):107-118.
Floyd P A, Leveridge B E. Tectonic environment of the Devonian Gramscatho basin, south Cornwall:Framework mode and geochemical evidence from turbiditic sandstones[J]. Journal of the Geological Society, 1987,144(4):531-542.
[40]
Bhatia M R, Crook K A W. Trace element characteristics of graywackes and tectonic setting discrimination of sedimentary basins[J]. Contributions to Mineralogy&Petrology, 1986,92(2):181-193.
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