Prediction of fracture gas bearing based on frequency-dependent AVAZ inversion in orthotropic medium

被引：0
|
作者：
Chen T. [1 ]
Cheng B. [1 ]
Xu T. [2 ,3 ]
Qian Z. [4 ]
Zou Z. [4 ]
机构：
[1] Key Laboratory of Earth Exploitation and Information Technology, Ministry of Education, Chengdu University of Technology, Sichuan, Chengdu
[2] School of Resources and Environment, University of Electronic Science and Technology of China, Sichuan, Chengdu
[3] Yangtze Delta Region Institute of University of Electronic Science and Technology of China（Huzhou）, Zhejiang, Huzhou
[4] National Engineering Research Center for Oil and Gas Exploration Computer Software, Beijing
来源：
Shiyou Diqiu Wuli Kantan/Oil Geophysical Prospecting | 2024年 / 59卷 / 03期
关键词：
Chapman model; gas-bearing prediction; orthogonal anisotropy; OVT domain seismic data; P-wave dispersion;
D O I：
10.13810/j.cnki.issn.1000-7210.2024.03.020
中图分类号：
学科分类号：
摘要：
The frequency- dependent AVO inversion method（FDAVO）can extract fluid- related anomaly information，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 prestack 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 derived based on the approximation of the P - wave reflection coefficient of OA media，and a new dispersion attribute 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. © 2024 Editorial office of Oil Geophysical Prospecting. All rights reserved.
引用
收藏
页码：567 / 580
页数：13
相关论文
共 33 条
  • [1] MARTINS J L., Elastic impedance in weakly anisotropic media, Geophysics, 71, 3, pp. D73-D83, (2006)
  • [2] Ll U Jingshou, DING Wenlong, XIAO Zikang, Et al., Advances in comprehensive characterization and prediction of reservoir fractures, Progress in Geophysics, 34, 6, pp. 2283-2300, (2019)
  • [3] GUO Z Q, ZHAO D Y, LIU C., A new seismic inversion scheme using fluid dispersion attribute for direct gas identification in tight sandstone reservoirs, Remote Sensing, 14, 21, (2022)
  • [4] ZONG Z Y, JI L X., Model parameterization and am - plitude variation with angle and azimuthal inversion in orthotropic media[J], Geophysics, 86, 1, pp. R1-R14, (2021)
  • [5] LIU Xiaojing, CHEN Zuqing, CHEN Chao, Et al., Fracture prediction method based on Fourier series of azimuthal elastic impedance, Oil Geophysical Prospecting, 57, 2, pp. 423-433, (2022)
  • [6] BAKULIN A, GRECHKA V, TSVANKIN I., Estimation of fracture parameters from reflection seismic data—Part II: Fractured models with orthorhombic symmetry, Geophysics, 65, 6, pp. 1803-1817, (2000)
  • [7] PSENCIK I, MARTINS J L., Properties of weak contrast PP reflection/transmission coefficients for weakly anisotropic elastic media, Studia Geophysica et Geo-daetica, 45, 2, pp. 176-199, (2001)
  • [8] BACHRACH R., Uncertainty and nonuniqueness in linearized AVAZ for orthorhombic media, The Leading Edge, 34, 9, pp. 1048-1056, (2015)
  • [9] PAN Xinpeng, ZHANG Guangzhi, YIN Xingyao, Azimuthally pre-stack seismic inversion for orthorhombic anisotropy driven by rock physics, Scientia Si-nica (Terrae), 48, 3, pp. 299-314, (2018)
  • [10] SMITH G C, GIDLOW P M., Weighted stacking for rock property estimation and detection of gas, Geophysical Prospecting, 35, 9, pp. 993-1014, (1987)
1234