Evolution of Miocene Fluvial Environments in Northern Pakistan

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A detailed sedimentological study of the Miocene Siwalik deposits of the Potwar Plateau in northern Pakistan is proposed. Temporally and spatially varying fluvial paleoenvironments will be reconstructed in terms of paleochannel and floodplain geometry and hydraulics, chemistry of lacustrine waters, nature of paleosols, distribution of animal and plant activity, river diversions, and deposition rates. Changes in these characters will be related to local, regional and/or global controls including climate, tectonism, and sediment supply. It will then be possible to understand an important period of evolution of land organisms in relation to changes in the physical and chemical environment over a period between 14 and 7 my B.P. The Siwalik deposits offer an unparalleled opportunity to realise these objectives because of: 1) excellent 3-D exposures of 3000 m + of strata; 2) previous studies of lithostratigraphy, vertebrate paleontology, and paleomagnetic age-dating; 3) independent constraints on climatic change and tectonic activity using geologic data now available for areas outside the depositional basin. Understanding of the evolution of fluival deposits (including the fossils they contain) in response to tectonism and climate has implications for rocks of all ages worldwide. Such knowledge has economic implications because fluival deposits are commonly reservoirs for water, oil, and gas, also are sources of coal, gold, uranium, and building materials.