叠前空变反演方法在致密薄储层预测中的应用

Application of pre-stack spatial variation inversion in tight and thin reservoir prediction

常规的叠前确定性反演在解决由复杂岩性引起的储层预测问题时,需要在确定性反演基础上再开展随机反演(或模拟)来提升分辨能力。笔者针对以叠前确定性反演结果约束随机岩性模拟存在横向控制难的问题,在基于贝叶斯框架下的反演目标函数中加入空变因子,实现一种横向控制的叠前空变反演方法。在松南断陷龙凤山工区中开展测试应用中,配合一种更为敏感的流体因子预测,实现对孔隙度小于5%的致密薄储层的叠前流体预测。

Pre-stack inversion is now a common way to predict complex reservoirs,with random inversion or simulation as an addition to improve the resolution of thin reservoirs.In view of the difficulty of lateral control in stochastic lithology simulation constrained by pre-stack inversion,the author proposes a new method of pre-stack spatial variant inversion,in which a spatial variable factor is added to the inversion objective function based on Bayesian framework.It is applied to the tight reservoir with less than 5%porosity in Longfengshan area of Songnan,a more sensitive fluid factor is inverted by the new method.