Provenance analysis of the Upper Paleozoic Shanxi to Lower Shihezi formations in north Ordos basin

With a series of gas discoveries being obtained in the clastic reservoirs in the Upper Paleozoic Shanxi Formation to Lower Shihezi Formation in the northern Ordos basin, their provenances have drawn our attentions. To figure out this problem, a systematic study was performed by using mathematical statistics methods and in combination with various data including the ancient land, genetic types of quartz grain, lithic types, heavy mineral combinations, and lithofacies paleogeographic framework. The results indicate that the terrigenous clastic sediments were sourced from the Alashan-Yinshan ancient land (the provenance) on the northern margin of the Ordos basin during the deposition from the Shanxi to Lower Shihezi formations, and that the provenance was closely related with the distribution of sedimentary systems and physical properties of reservoir sandbodies in the northern Ordos Basin.