利用扩展弹性阻抗识别碳酸盐岩储层  

An extended elastic impedance method and its application to detect carbonate reservoir

作　　者：张勇刚 范国章 王红平 王朝锋 杨柳 左国平 刘艳红 ZHANG Yonggang;FAN Guozhang;WANG Hongping;WANG Chaofeng;YANG Liu;ZUO Guoping;LIU Yanhong(Petrochina Hangzhou Research Institute of Geology,Hangzhou 310023,China)

机构地区：[1]中国石油杭州地质研究院,杭州310023

出　　处：《物探化探计算技术》2022年第4期410-416,共7页Computing Techniques For Geophysical and Geochemical Exploration

基　　金：国家科技重大专项(2019D-4309)。

摘　　要：某海上研究区受巨厚盐层覆盖和多期火成岩侵入影响,盐下碳酸盐岩储层地震响应规律复杂,常规的AVO分析对岩性和流体的识别存在局限性。扩展弹性波阻抗反演技术是弹性波阻抗反演的进一步推广,能充分挖掘地质体的弹性信息和叠前道集振幅随偏移距变化的响应特征,是对截距、梯度属性分析的深化应用,包含更丰富的岩性和流体信息,是一种有效的流体检测技术。这里在论述了扩展弹性波阻抗的概念以及反演方法原理的基础上,给出了利用扩展弹性波阻抗反演进行岩性或流体检测的具体流程,以井点岩石物理参数或储层参数为基础,通过与叠前道集计算的井点处不同角度弹性波阻抗拟合对比后,检测出拟合性最优的前几项敏感及其对应的理论入射角参数值,反演特定角度的扩展弹性波阻抗体和按拟合函数计算其对应的敏感岩石物理参数体。研究区的扩展弹性波阻抗反演实用效果表明,反演结果计算的敏感岩石物理参数与点上盲井实测参数吻合度高,剖面上进行的储层预测与钻井吻合较好,平面上的储层展布符合地质认识,基于扩展弹性波阻抗反演的储层预测技术,在碳酸盐岩储层识别方面具有良好的实用性和有效性。The seismic response of carbonate reservoir properties and fluid changes in a submarine research block are complex,and it is difficult to identify by conventional AVO techniques.The extended elastic impedance(EEI)inversion technique is further extension comparing with elastic impedance(EI).This makes full use of the elastic information of geological body and the response characteristics of the amplitude of pre-stack gathers along with the offset,intercept and gradient properties are deepen applied.More information about lithology and fluids are revealed.It is an effective technique for the fluid detection and recognition on the basis of briefly presenting the concept,method and principle of EEI.This paper proposes the specific process flow of lithology and fluid detection by using EEI inversion.The key step is to obtain the optimal fluid theory angles,and then invert the preferred angle's EEI volumes and calculate the sensitive rock physics parameters volumes.The practical application in the region of interest shows that the extracted sensitive rock physics parameters curves match with the wireline logging in the location of blind well,and the reservoir prediction on the section is in good agreement with the well condition.The reservoir distribution on the plane conforms to the geological understanding.It's verified that the EEI inversion technique demonstrates feasibility and validity in this block.

关 键 词：碳酸盐岩 AVO分析 扩展弹性阻抗 流体检测 理论入射角 

分 类 号：P631.4[天文地球—地质矿产勘探]