Data for: Gecochemical characteristics of Lower Silurian shale gas in the Changning-Zhaotong exploration blocks, southern periphery of the Sichuan Basin
Table 1. Thermal maturity determined through reflected light microscopy. The relationship between maximum vitrinite-like material reflectance (Rom) and random vitrinite-like reflectance (Ran) is shown is given by Rom= Ran (mean value)*1.064. Dozens of core samples were collected from the production layer of exploration wells of N12, YS1, and Z4 in the CZ blocks (Table 1). Using equations proposed by the literature Zhong and Qin, (1995), the Maximum vitrinite-like material reflectance (Rom) data has been converted into the equivalent vitrinite reflectance (Ro), which ranges from 2.35% to 3.44%, with an average of 3.03% (Table 1), which is similar to that of the Changning area (2.3%–3.8%, average: 2.9%) (Zou et al., 2016; Wang et al., 2017, 2018). Table 2.Table 2 Component and isotope properties of Longmaxi Formation shale gas in the Zhaotong area, southern periphery of the Sichuan Basin. Gas samples in this research were taken from the newly expanded shale gas platforms at stable production stage in the CZ blocks (Fig. 1). After the containers had been repeatedly flushed and refilled, gases were gathered in steel cylinders (resistant up to 15 MPa) at ~5 MPa's pressures. The gas composition, stable carbon and hydrogen isotopes had been analyzed at PetroChina Research Institute of Petroleum Exploration & Development in Beijing in 2017, and the methods were performed (Dai et al., 2012; Gong et al., 2014; Liu et al., 2018).