Abstract:

In order to understand main controlling factors and quantitative characterization of oil-bearing of complex structural trap in west sag of Liaohe depression，the 103 complex structural traps were researched on the base of statistical analysis of geology and R-factor analysis. The results showed that the oil fullness degree of complex structural trap was controlled by the distances between the center of expulsion hydrocarbon and trap, the fluid potential energy, the thickness of caprock and sand body and the numbers of faults cutting the reservoir. The geological analysis showed that the oil fullness degree of the complex structural traps will benefit from the close distance from the center of expulsion hydrocarbon, the relatively low fluid potential energy and the thickness of sandrock in reservoir is less than fault throw and the fault throw is less than the thickness of mudstone in caprock. The comprehensive quantitative connection models between the oil fullness degree and the controlling factors of complex structural traps are established by using the methods of correlation analysis and multiple regression analysis. The 21 complex structural traps are predicted and the validation results of the forecast model indicate that the value of 80% forecast oil fullness degree of the trap is consistent to the real value.

Key words: complex structural trap, oil-bearing, main controlling factors, quantitative model, west sag of Liaohe depression, petroleum gas