Jornal de Geologia e Geofísica
Acesso livre

Abstrato

Paleocurrents and Paleohydraulics Studies of the Proterozoic Kolhan Siliciclastic Unit (India): A Case Study from the Chaibasa-Noamundi Basin, Jharkhand, India

Smruti Rekha Sahoo

Detailed palaeocurrent and palaeohydraulic analyses of the fluvio-deltaic Proterozoic Kolhan siliciclastic unit has provided new insights into the sedimentological knowledge of the fan delta deposition, allowing for the reconstruction of paleogeographic and paleoclimatic conditions prevalent in the Chaibasa-Noamundi intracratonic basin of India. The azimuth reading of cross-bed stratifications of fluvial deposits and the preferential grain orientation of different lithofacies have indicated at least two major paleo-flow systems, NW and NE trending. The local occurrence of sedimentary structures of high energy depositional environments has indicated the superimposition of retrogradational strata pertaining to an older progradational fan complex. The fluvio-deltaic Proterozoic sedimentation has followed the emplacement of volcanic dykes, basic in composition, indicating a thermal rejuvenation of the continental crust. Finally, the partial development of limestones and dolomites in the Kolhan succession has pointed out the peneplanation of the cratonic areas and the development of carbonate sedimentation on stable carbonate platform.