A comprehensive fluid identification method for carbonate reservoirs considering pore shapes: A case study of the fourth member of the Ordovician Majiagou Formation,Ordos Basin
WANG Yong-Gang1,2(), YAO Zong-Hui1,2, YANG Qi-Yu3,4, LI Jing-Ye3,4, SONG Wei3,4
1. Research Institute of Exploration and Development,Changqing Oilfield Company,PetroChina,Xi'an 710018,China 2. National Engineering Laboratory for Exploration and Development of Low-Permeability Oil & Gas Fields,Xi'an 710018,China 3. State Key Laboratory of Petroleum Resources and Prospecting,Beijing 102249,China 4. College of Geophysics,China University of Petroleum(Beijing),Beijing 102249,China
The dolomite reservoirs of the fourth member of the Majiagou Formation in the Ordos Basin are characterized by thin layers,tightness,complex pore shapes,strong heterogeneity,and relatively weak seismic responses.The mechanisms behind the seismic prediction of the reservoirs remains uncertain, making fluid identification challenging.Traditional geophysical methods based on a single attribute fail to accurately predict fluids.Therefore,by comprehensively accounting for the pore shapes and connectivity,this study proposed a new fluid identification method using petrophysical modeling and analysis,as well as wave theory-based prestack AVO inversion,frequency-dependent AVO inversion of fluid factors,and probabilistic neural network(PNN)-based prediction of pore structure parameters.This method,comprehensively considering the impacts of elastic parameters,physical parameters,and dispersion properties,achieve remarkable results.Compared to traditional single-attribute fluid identification method,the proposed method demonstrates higher accuracy,particularly for gas-bearing areas,fully verifying its effectiveness in fluid identification and highlighting its potential for widespread application.
王永刚, 姚宗惠, 杨骐羽, 李景叶, 宋炜. 考虑孔隙形状的碳酸盐岩储层流体综合识别方法研究及应用——以鄂尔多斯盆地奥陶系马家沟组四段为例[J]. 物探与化探, 2025, 49(1): 177-188.
WANG Yong-Gang, YAO Zong-Hui, YANG Qi-Yu, LI Jing-Ye, SONG Wei. A comprehensive fluid identification method for carbonate reservoirs considering pore shapes: A case study of the fourth member of the Ordovician Majiagou Formation,Ordos Basin. Geophysical and Geochemical Exploration, 2025, 49(1): 177-188.
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doi: 10.3969/j.issn.1000-1441.2022.05.007