Figure 3: The lithologic log of the co-sedimentary system of evaporites and mudstone and their representative photos in the Es4 from Hk1 Well in Dongying depression. a:3438.48m, salt rock, salt grain in the middle is larger than the edge of the salt rock. b:3769.65m, dark gray mudstone with thin layers of salt and a deformation of bedding. c: 3771.45m, salt rock with two rhythmic. d: 3772.2m, salt rock with three rhythmics e: 3972.1m, purple mudstone with white light-colored and rhythm with deformation f: 3975.65m, purple argillaceous siltstone with bedding inclined plate g: 4499.3m, dark purple-red mudstone with mud-gravel h: 4506.6m, dark-purple, light gray rhythm bedding with calcite particles and bedding deformation 1, mudstone; 2,sandy mudstone; 3, oil shale; 4, calcareous clay; 5, gypsum mudstone; 6,saline mudstone; 7, soft mudstone; 8, siltstone; 9, dolomitic siltstone; 10, fine sandstone; 11, argillaceous dolomite; 12, gypsum; 13, gypsum salt rock; 14. Salt rock