超压对油气成藏的影响及其评价

Inf luence and Evaluation of Overpressure on Oil
and Gas Reservo ir Form ing

 杨鸣

Yang Y iming

 大庆石油学院

Daqing Petroleum Institute, Daqing
163318, China

 世界含油气盆地中超压分布广泛, 且对油气勘探开发影响深远。通过对我国几个超压盆地的研究分析得到, 超压对有机质热演化的抑制作用在不同地区影响程度明显不同。超压条件下有效应力引起的机械压实程度减弱, 及有机酸对矿物的溶解作用使深埋超压储层保持较高的孔隙度和渗透率。超压为油气运移提供动力, 并为油气运移拓宽通道; 异常超压还可以提高盖层的封闭能力。文中还采用神经网络方法对超压在油气成藏的影响进行评价。

The overpressure is w idely d istr ibu ted in the o i-l bear ing
basin o f thew or ld , and it has g rea t influence on the o il and
gas exploration. Through the study of som e overpressured
basins in ch ina, it is considered that overpressure has
d ifferen t effec t on the evo lution o f o rganic m atte r in d ifferent
area. The w eak m echanical compaction caused by the low
effective stress in ove rpressured cond itions leads to the
preservation of relativ ely h igh po rosity and perm eab ility fo r
the deeply-bur ied sandstone. The overpressure prov ides
m otive and b igger access fo r the o il and gas m igration.
Overpressure has also im proved the sealing ability of caprock.
The influence of overpressure on the o il and gas accumu la tion
can be eva luated by the neura l ne tw ork.