“…With reference to the requirements of the "13th Five-Year Plan for Coal Industry Development" formulated by the Chinese government, the overall layout of China's coal development is divided into the east development region (including Hebei, Shandong, Beijing, Tianjin, Jiangsu, Zhejiang, Fujian, Guangdong, Hainan, and Taiwan), central development region (including Shanxi, Henan, Anhui, Jiangxi, Hubei, and Hunan), northeast development region (including Heilongjiang, Jilin, Liaoning), and west development region (Neimenggu, Shaanxi, Ningxia, Gansu, Qinghai, Xinjiang, Tibet, Chongqing, Yunnan, Guizhou, Sichuan, and Guangxi) [24], as shown in Figure 4.…”