Genetic Types and Source of the Upper Paleozoic Tight Gas in the Hangjinqi Area, Northern Ordos Basin, China

Figure 8

Cross-plots of δ¹³C₂ versus δ¹³C₁ (a) and δ¹³C₃ versus δ¹³C₂ (b) of tight gas from the Hangjinqi area. The trend lines for gases from kerogen type III of Niger Delta and kerogen type II of Delaware/Val Verde Basin are from Rooney et al. [3], and the trend lines for gas from kerogen type III of Sacramento Basin are from Jenden et al. [41]. δ¹³C₂ and δ¹³C₃ ranges for coal-type and oil-type gases in (b) are from Dai [42]. Data of the O₁m gas in the Jingbian gas fields are from Dai [18].

(a)

(b)