基于HTI介质走时反演的各向异性参数建模与AVAZ反演  

Modeling of anisotropic parameters based on HTI medium travel⁃time inversion and AVAZ inversion

作　　者：周城 杨宇勇 周怀来[1,2] 王元君 陶柏丞 余沛林 ZHOU Cheng;YANG Yuyong;ZHOU Huailai;WANG Yuanjun;TAO Bocheng;YU Peilin(School of Geophysics,Chengdu University of Technology,Chengdu,Sichuan 610059,China;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu,Sichuan 610059,China;China West Normal University,Nanchong,Sichuan 637002,China)

机构地区：[1]成都理工大学地球物理学院,四川成都610059 [2]油气藏地质及开发工程国家重点实验室,四川成都610059 [3]西华师范大学,四川南充637002

出　　处：《石油地球物理勘探》2023年第4期949-960,969,共13页Oil Geophysical Prospecting

基　　金：国家自然科学基金项目“含直立裂缝页岩储层横波分裂频变响应机理及裂缝尺度预测研究”(42204138);四川省自然科学基金青年基金项目“含一组直立裂缝正交各向异性介质的多波响应与裂缝预测”(2022NSFSC1150)联合资助。

摘　　要：传统的各向异性反演方法主要利用测井资料和层位数据通过插值构建初始模型,其模型精度较低。为此,针对地震各向异性反演的初始模型的建立问题,在HTI介质假设下,利用炮检距矢量片(OVT)数据的走时信息获取各向异性参数(ε、δ),然后基于各向异性参数之间的经验关系估计另外一个各向异性参数γ,从而建立初始各向异性参数模型。再利用各向同性反演获得的弹性参数建立初始弹性参数模型。最后,基于Rüger反射系数近似公式,利用高斯—牛顿法反演弹性参数和各向异性参数。模型数据与实际数据的应用表明,所提方法可以在不受测井数据约束的情况下实现高精度的各向异性参数反演,为获取裂缝性储层中的微裂缝信息提供依据。Traditional methods for anisotropic inversion primarily rely on well logging data and layer information to construct initial models through interpolation,resulting in low model accuracy.To address this issue in establishing the initial model of seismic anisotropic inversion,under the assumption of horizontal transverse isotropy(HTI)medium,the travel‑time information from offset vector tile(OVT)data is utilized to extract anisotropic parameters(εandδ).Then,another anisotropic parameterγis estimated based on the empirical relationship between the anisotropic parameters,so as to establish an initial anisotropic parameter model.Furthermore,an initial elastic parameter model is established by using the elastic parameters obtained from isotropic inversion.Finally,On the basis of the Rüger approximation formula for reflection coefficients,the elastic parameters and anisotropic parameters are retrieved by the Gauss‑Newton method.Application of the proposed method to model and real data demonstrates its ability to achieve high‑precision anisotropic parameter inversion without being constrained by well logging data,providing a basis for acquiring micro‑fracture information in fractured reservoirs.

关 键 词：HTI介质 OVT数据 裂缝型储层 弹性参数 各向异性参数 初始模型 反演 

分 类 号：P631[天文地球—地质矿产勘探]