A low degree of exploration is the actuality of Wuzhishan-Meigu area in Southwest Sichuan Province as none exploratory well is drilled. The distribution, thickness, abundance, types and maturity of potential source rocks are studied based on the field geological investigation and chemical analysis. The results show that the regional main source rocks are Qiongzhusi Formation of Lower Cambrian, Linxiang-Wufeng Formation of Upper Ordovician, Longmaxi Formation of Lower Silurian, Maokou Formation-Qixia Formation of Lower Permian and Xujiahe Formation of Upper Triassic, including carbonate source rocks and mud source rocks. Total organic carbon method is used with the simulation technique to calculate the hydrocarbon genetic content. The total volume of hydrocarbons generation amounts to 1 193.89×1011 cubic meters and total resources, 5.157×1011 cubic meters, which indicates the area has a great exploration potential. It is believed that the Longmaxi Formation is the best major effective source rocks, with wide distribution, big thickness and high abundance of organic matter, with the resources up to 2.12×1011 cubic meters, about 41.28% of the total resources. Especially, the organic matter abundance is higher and reaches from 0.32% to 6.07% in middle and lower parts of the Formation. Qiongzhusi Formation of Lower Cambrian is the second effective, with the total resource up to 1.218×1011 m3. The source rocks in Qixia Formation and Maokou Formation contain abundant organic matter, with TOC value more than 0.2% in most part of the study area, accounting for 0.99×1011 m3,0.42×1011 m3 respectively. While Linxiang-Wufeng Formation and Xujiahe Formation are thin, with restricted distribution of the source rocks and limited generation potential of hydrocarbons. An integrated study shows that the northern part of Leibo nose salient, Mabian-Suijiang Sag and the middle part of Liangdong-Meidu Fault Depression are prospective exploration regions, because of their abundant hydrocarbon resources and good conditions of hydrocarbon preservation.
effective source rockresources evaluationhydrocarbon-generating intensityresources potentialWuzhishan-Meigu area
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