Alkyl Dibenzothiophenes Tracing the Crude Oil Filling Pathway in the Fuyang Oil Layer of Wangfu Sag, Songliao Basin

Based on the thermodynamic stability and hydrogen bond mechanisms, alkyl dibenzothiophene molecular ratios, 4-/1-MDBT, and 4,6-/1,4-DMDBT, are used to characterize organic maturity and oil migration, which can act as molecular tracers for the filling orientation and pathway in oil reservoir. The results show that the well Shuang32 is the filling point which is close to the source kitchen. Three advantaged oil migration and filling pathways have been discovered, the first one is that oil is charged from well Shuang32 to well Shuang26- well Shuang301- well Shuang31 in northeast orientation, the second one is that oil is charged from well Shuang32 to well Shuang34- well Shuang36 in southwest orientation, the third one is that oil is charged from well Shuang 32 to well Chang502- well Shuang 23 in west-northwest orientation.