ABSTRACT: The Upper Carboniferous-Lower Permian strata of the Nilawahan Group, Salt Range, Pakistan comprises the Tobra, Dandot, Warchha and Sardhai formations which represent the remnants of southern Gondwanaland. In this study, biostratigraphic and facies information was utilized to identify the sequences, their tectono-stratigraphic evolution and occurrence of the paleoclimatic perturbations in the study area. The stratigraphic comparison of the Nilawahan Group with the stratigraphic record of southern Gondwanaland (the Indian Peninsula, Arabia, South Africa, and Australia) suggests three phases of deposition. These phases correspond to the Pre-Permian Rift, Syn-Permian Rift and Post-Permian Rift tectonic and climatic regime. The Pre-Permian Rift deposits consist of the glaciogenic facies of the Tobra Formation and tidally influenced marine facies of the Dandot Formation, which were deposited in the embryonic intra-cratonic basins during the Gzhelian-Lower Artinskian very cold-cold climatic regime. The Syn-Permian Rift Phase corresponds to the outpouring of Panjal volcanics and deposition of the regressive fluvial facies of the Warchha Sandstone within the rift basin during the Artinskian cool-warm climatic regime. The Post Permian Rift phase during Kungurian-Wordian saw a eustatic sea level rise that deposited the Sardhai Formation in the sag-type shallow marine basin in a warm-hot climatic regime. This study supports the idea of Late Paleozoic multiple discrete episodes of glaciation, rather than a single ice cap thatwas separated by strata that records glacial retreat, eustatic sea level rise and a distinct paleoclimatic regime.

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