Accumulation Mechanism of Marine Shale Gas Reservoir in Anticlines: A Case Study of the Southern Sichuan Basin and Xiuwu Basin in the Yangtze Region

Figure 3

Stratigraphic column and core photos of the Upper Ordovician Linxiang Formation, the Upper Ordovician Wufeng Formation no. 1 section of the Lower Silurian Longmaxi Formation, and the no. 2 section of the Lower Silurian Longmaxi Formation in Jiaoye-1 Well. (a) The Upper Ordovician Linxiang greenish-grey warty limestone, 2419 m; (b) the Upper Ordovician Wufeng Formation no. 1 section of the Lower Silurian Longmaxi black siliceous shale, 2401 m; (c) the no. 2 section of the Lower Silurian Longmaxi grey silty shale, 2319 m. See Figure 1 for the well locations.