基于地震岩相约束下的孔隙度预测技术  

Porosity Prediction Technology Based on Seismic Rock Phase Confinement

作　　者：高强 GAO Qiang(SINOPEC Geophysical Research Institute Co.,Ltd.,Nanjing Jiangsu 211103)

机构地区：[1]中石化石油物探技术研究院有限公司,江苏南京211103

出　　处：《中国科技纵横》2025年第3期128-131,共4页China Science & Technology Overview

摘　　要：致密砂岩储层具有低孔、低渗、非均质性强和复杂的孔隙结构等特征,储层物性参数与弹性参数之间的关系异常复杂。当前,岩石物理反演方法往往基于岩相均匀分布的假设,弱化了岩相横向变化快、固结程度差异大以及孔隙结构复杂等特点,从而影响孔隙度反演精度。基于此,本文通过工区砂、泥岩的敏感性分析构建了砂岩识别因子,实现了对砂岩相和泥岩相的精准划分。在砂岩相基础上,基于能够表征成岩固结程度、孔隙和裂缝的PDEM模型和Gassmann方程,构建了孔隙度反演算法,通过模拟退火算法预测孔隙度。同时,将该方法应用于四川盆地W工区致密砂岩储层孔隙度定量预测,实际测井和地震数据应用结果表明,该方法可以有效提高致密砂岩储层孔隙度的预测精度。Tight sandstone reservoirs have characteristics such as low porosity,low permeability,strong heterogeneity,and complex pore structure,the relationship between reservoir physical parameters and elastic parameters is exceptionally complex.The current rock physics inversion methods are often based on the assumption of uniform distribution of lithofacies,simplified the characteristics of fast lateral changes in lithology,large differences in consolidation degree,and complex pore structure,this affects the accuracy of porosity inversion.Based on this,this article first constructs sandstone identification factors through sensitivity analysis of sand and mudstone in the work area,accurate classification of sandstone and mudstone phases has been achieved.Then,on the basis of sandstone facies,based on the PDEM model and Gassmann equation that can characterize the degree of diagenetic consolidation porosity and fractures,constructed a porosity inversion algorithm,predicting porosity through simulated annealing algorithm.Finally,the method was applied to quantitatively predict the porosity of tight sandstone reservoirs in the W work area of the Sichuan Basin,the application results of actual logging and seismic data show that,it can effectively improve the prediction accuracy of porosity in tight sandstone reservoirs.

关 键 词：致密砂岩储层 岩相识别 岩石物理反演 孔隙度预测 

分 类 号：TE132[石油与天然气工程—油气勘探]