Abstract: There is great difference in petroleum properties and geochemistry between the falut zone and the anticline belt. In fault zone petroleum (oil) density is between 0.73 g/cm³ and 0.86 g/cm³, the average content of CH₄ is 87.06%, the value of δ¹³C₁ is between -40.96 ‰ and -44.22 ‰; petroleum density in anticline belt is between 0.85 g/cm³ and 0.95g/cm³, the average content of CH₄ is 73.59%, the value of δ¹³C₁ is between -46.38 ‰ and -47.83 ‰. All of this indicated that petroleum accumulated in multi-stage, fluvial sand body is first filled with mature petroleum in anticline belt, and high mature petroleum generated in middle-late Jurassic accumulated in fault zone.