Fig. 1

(a) Geological structure map of Ordos Basin. (b) Stratigraphic histogram of Q36 well in Benxi Formation 8 # coal seam of Ordos Basin. (Fig. 1a was created by Yu Li and was drawn using CorelDRAW 2020 (64-Bit) software. The version number of this software is v22.0.412 and the URL link is https://www.coreldrawchina.com.).