石油地球物理勘探2024，Vol.59Issue(3)：567-580,14.DOI:10.13810/j.cnki.issn.1000-7210.2024.03.020
基于正交各向异性介质频变AVAZ反演的裂缝含气性预测
Prediction of fracture gas bearing based on frequency-dependent AV AZ inversion in orthotropic medium
摘要
Abstract
The frequency-dependent AVO inversion method(FDAVO)can extract fluid-related anomaly infor-mation,but it is difficult to apply to fractured reservoirs because it fails to consider the effect of anisotropy in real reservoirs.In addition,the anisotropy is often frequency-dependent,which facilitates the identification of effective fractures using OVT domain pre-stack seismic data.Therefore,a frequency-dependent AVAZ(OA-FDAVAZ)inversion method for gas content prediction based on orthotropic(OA)media is proposed.Firstly,based on the numerical simulation of the Chapman model,the variation characteristics of elastic parameters with frequency and incidence angle are analyzed.Then,the objective equation of OA-FDAVAZ inversion is de-rived based on the approximation of the P wave reflection coefficient of OA media,and a new dispersion attri-bute Iani is constructed.Finally,the least square method is used to invert the OA dispersion properties.The model test results show that the OA dispersion property of the gas-bearing fractured layer is obviously stronger than that of the water-bearing fractured layer,while the anisotropic layer without cracks has a weak dispersion response,which verifies the sensitivity of the proposed dispersion property to fluid.The application results of OVT domain pre-stack seismic data show that the prediction results of the OA dispersion attribute are in good agreement with the drilling results.Compared with traditional methods,the proposed method is less affected by background interference and can accurately characterize the spatial distribution characteristics of gas bearing in fractures in reservoirs.关键词
正交各向异性/Chapman模型/纵波频散/OVT域地震数据/含气性预测Key words
orthogonal anisotropy/Chapman model/P-wave dispersion/OVT domain seismic data/gas-bearing prediction分类
天文与地球科学引用本文复制引用
陈天杰,程冰洁,徐天吉,钱忠平,邹振..基于正交各向异性介质频变AVAZ反演的裂缝含气性预测[J].石油地球物理勘探,2024,59(3):567-580,14.基金项目
本项研究受国家自然科学基金项目"基于应力诱导各向异性与岩石力学性质的深层页岩储层可压裂性评价方法研究"(42074160)、四川省自然科学基金项目"深层—超深层页岩储层'甜点'要素智能预测与一体化表征方法研究"(2023NSFSC0255)和中国石油天然气集团有限公司重大科技专项"多物理场高精度油气地球物理探测技术与装备研究"(2023ZZ05)联合资助. （42074160）
