基于White层状模型的流度响应特征分析与反演方法  

Response characteristic analysis and inversion method of mobility based on White′s layered patchy-saturated model

作　　者：魏乐乐 甘利灯[1] 丁骞 杨志芳[1] 王大兴[2] 张昕[1] 杨昊[1] 周晓越 WEI LeLe;GAN LiDeng;DING Qian;YANG ZhiFang;WANG DaXing;ZHANG Xin;YANG Hao;ZHOU XiaoYue(Geophysical Department,RIPED,PetroChina,Beijing100083,China;PetroChina Changqing Oilfield Company,Xi′an 710018,China)

机构地区：[1]中国石油勘探开发研究院,北京100083 [2]中国石油长庆油田分公司勘探开发研究院,西安710018

出　　处：《地球物理学报》2023年第6期2611-2620,共10页Chinese Journal of Geophysics

基　　金：中国石油天然气股份有限公司科技项目(kt2021-12-02);中国石油天然气集团有限公司前瞻性基础性技术攻关课题(2021DJ3701)资助。

摘　　要：流度是指某相流体有效渗透率与流体黏度的比值,反映了储层岩石骨架中孔隙结构的渗透性和孔隙流体的黏度的共同作用.目前,有关流度的研究主要集中在流度属性的计算等方面,然而基于岩石物理模型来探讨流度对地震波频散衰减特征的影响以及流度的反演方法研究较少.注意到,在White层状斑块饱和模型中,频散衰减方程建立了流度与相速度和逆品质因子之间的关系.基于此模型,首先针对两种砂岩储层及两种含气饱和度,应用数值模拟研究了流度对地震波频散衰减特征的影响.其次,提出了利用粒子群算法和速度频散数据进行流度反演的方法.最后,苏里格岩心实测速度频散数据的反演应用验证了反演方法的有效性与准确性.结果表明:流度的变化对纵波的频散衰减影响显著.一般来说,在疏松高孔、含气饱和度较低的砂岩储层中,流度对地震响应特征的影响更为显著.应用于实际资料的反演结果验证了反演方法可靠稳定、收敛性好,精度较高.上述研究为流度的岩石物理反演提供了理论依据和新的技术思路.Fluid mobility refers to the ratio of the effective permeability to the fluid viscosity of a fluid,and it reflects the interaction of permeability and fluid viscosity in the rock matrix of a reservoir.Studies have focused mainly on mobility attributes calculation and seldom dealt with mobility effects on the seismic responses of reservoirs and the inversion method based on petrophysical model.It is noted that there is a correspondence between mobility and dispersion and attenuation of the White′s layered patchy-saturated model.On the basis of White′s theory,we firstly employ numerical simulation to investigate mobility effects on seismic dispersion and attenuation for two typical sandstone reservoirs at two gas saturations.Secondly,we propose a method to inverse mobility value using P-waves dispersion data by particle swarm optimization.Finally,case studies of mobility inversion using core data from the Sulige gas field are given to verify the effectiveness and accuracy of our proposed method.The results show perceptible mobility effects on P-wave dispersion and attenuation.In general,mobility has a notable effect on seismic responses of unconsolidated sandstone reservoirs with large porosity and low gas saturation.Inversions on core data show the method is reliable,stable and convergent,and the inverted results are of high precision.All these theoretical findings would provide the basis and new technical ideas for mobility prediction.

关 键 词：层状斑块饱和模型 流度 频散 参数反演 粒子群算法 

分 类 号：P631[天文地球—地质矿产勘探]