Fig. 4

Distribution characteristics of parameters of stable biomarkers in representative well sections or sections in Tarim Basin(Data sources: Chen et al.35). (a) TDSI = triaromatic dinoflagellate steroids/(triaromatic dinoflagellate steroids + 3-methyl-24-ethyl-triaromatic steroids); (b) C26 20 S/C28 20 S TAS = C26 20 S triaromatic steroids/C28 20 S triaromatic steroids; (c) (C26R + C27S)/C28S TAS= (C26 20R + C27 20 S) triaromatic steroids/C28 20 S triaromatic steroids; (d) C27/C28 20R TAS = C27 triaromatic steroids/C28 20R triaromatic steroids; (e) ATMBs: 1-alkyl-2,3,6-trimethylbenzenes.