Sedimentary Provenance Study of Lower Permian Shanxi Formation in Southwestern Ordos Basin

Provenance was the most basic and important work in sedimentary facies study,it was beneficial for determining its location and ascertaining sedimentary transporting way,and identifying the distribution law of depositional system and sandbody.In Lower Permian Shanxi Formation,the depositional system was distributed from north to south in Ordos Basin.The northern provenance was regarded as the leading factor of sedimentary facies,so it was relatively weaker in the southern provenance study.It is a critical problem widely concerned by all the oilfield exploration decision makers and it is also the basis of making the plan of future exploration.The main and subordinate provenance of Southwestern Ordos Basin in Shanxi Period is analyzed for forecasting prospective reservoirs according to sedimentary petrology(composition,heavy mineral assemblage,palaeocurrent direction,cathodoluminescence etc.),as well as sandstone thickness.