The study presents integrated palynofacies,organic carbon isotope,and biomarker data to reconstruct palaeoenviromental setting for the Permian sediments(borehole MGK-6)of the Kachinapalli block of the Godavari Valley Coalfield,southern India.The palynofacies data reveal three distinct palynofacies(A-C)as follows.Palynofacies A is dominated by abundant arborescent vegetation(glossopterids and conifers)along with structured organic matter,suggesting freshwater forest swamps in proximal settings.Palynofacies B is dominated by abundant degraded organic matter and amorphous organic matter,suggesting lakeshore/flooded palaeomires in slightly dismal settings.It has a high water level in the hinterland,which enables bacterial degradation of organic matter and establishes low-oxygenation conditions within the water column.These conditions would have provided grounds for the accumulation of either degraded or amorphous organic matter.Palynofacies C is dominated by the abundance of charcoal/opaque phytoclasts,indicating prolonged transportation or post-depositional alteration,suggesting a highly-oxidizing condition in distal settings.The bulk organic δ13C range(-25.1‰ to-20.9‰)in the borehole MGK-6 is in close agreement with the global Permian records.This study also shows a weak but statistically significant correlation with the major forms of palynofacies A and C.The inter-linked behaviour of bulk organic δ13C and palynofacies suggests that the changes in palaeobiogeography/palaeodepositional settings were most likely driven by the change in mean annual precipitation.The biomarker study shows the presence of n-alkane from C15 to C31 with unimodal and bimodal distribution patterns,revealing the source materials as vascular plants and microbially-altered organic matter.The combined palynofacies,organic carbon isotope,and biomarker data provide vital clue to salient findings for the development of envi-ronmental conditions of Godavari Valley Coalfield during lower Gondwana sedimentation.

Neha Aggarwal;Runcie Paul Mathews;Arif Husain Ansari;Biswajeet Thakur;Shailesh Agrawal

Birbal Sahni Institute of Palaeosciences,53 University Road,Lucknow 226007,India

古地理学报（英文版）

[1]Neha Aggarwal;Runcie Paul Mathews;Arif Husain Ansari;Biswajeet Thakur;Shailesh Agrawal-.Palaeoenvironmental reconstruction for the Permian(lower Gondwana)succession of the Godavari Valley Coalfield in southern India based on a combined palynofacies,carbon isotope,and biomarker study)[J].古地理学报（英文版）,2022(01):123-144

Palaeoenvironmental,Coalfield,palynofacies,palaeoenviromental,MGK,Kachinapalli,Palynofacies,arborescent,glossopterids,swamps,palaeomires,phytoclasts,palaeobiogeography,palaeodepositional

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