综合多种地震信息预测油气富集区的模糊数学方法

A fuzzy mathematical method for predicting hydrocarbon accumulation area by comprehensively analysing multiple kinds of seismic information

本文分析了多种地震信息(振幅、相位、频率、构造曲率、层速度、视极性、低速层厚度)与油气的模糊关系,进而建立了各种地震信息的隶属函数。通过多层次的综合评判,利用λ水平集合分类,预测了高产、低广和非产区,从而为钻井提供了可靠的定井资料。文中以四川某构造上10口井的地震资料为例,用上述方法进行了评判和分类,并通过另外7口井资料作回代,在符合率较好的情况下,预测了部分构造的高产、低产和非产区。其结果说明本方法可作为预测油气富集区的方法之一,较之其它方法(如数理统计方法)有较明显的优点:不仅可预测出产区和非产区,而且可预测出高产区和低产区,还便于实现油气检测的自动化。

Having analysed the fuzzy relations between amplitude,phase,fre- quency,structure curvature,interval velocity,apparent polarity or the thickness of low velocity layer and hydrocarbon accumulation,the authors established the membership functions of these kinds of seismic information.using different decisions and λ horizontal cluster sorting, high,low and non-productive areas can be respectively predicted,thus bringing reliable data for locating well sites.The seismic data at 10 wells on a structure in Sichuan Province were taken as an example for experiment.The decision and sorting were made according to above me- thod,and the seismic data at other 7 wells were used to check the ex- periment.The high,low and non-productive areas in a part of the struc- ture were quite Successfully ascertained.It is shown that this method can also be used to predict hydrocarbon accumulation area.The superio- rities of this method to others(for example,mathematical statistics method)are as follows:(1)it not only predicts productive area but also separates high-productive area from low-productive area,and(2)it favours achieving automatic hydrocarbon indication.