The Exquisite Comparison of Shale Mineralogical-Geochemical Characteristics between Chang 7 Member and Chang 9 Member in Yanchang Formation, Ordos Basin
Significant amounts of unconventional oil and gas resources have been discovered in the Yanchang Formation of Ordos Basin.Shale layers deposited in Chang 7 member (divided into Chang 7-2 submember (C7-2SM) and Chang 7-3 submember (C7-3SM) and Chang 9 member (C9M)) are the main source rocks.Based on the comparison of mineralogical and geochemical ch