石油科学通报2025，Vol.10Issue(6)：1114-1129,16.DOI:10.3969/j.issn.2096-1693.2025.01.026
走滑断裂控制的碳酸盐岩缝洞型储层非均质性及其影响因素
Heterogeneity and controlling factors of the strike-slip fault-controlled carbonate fracture-vuggy reservoirs
摘要
Abstract
Carbonate fractured-vuggy reservoirs in the Middle-Lower Ordovician of the Tarim Basin are strongly controlled by deep strike-slip faults.Their pronounced heterogeneity has become a key challenge to the efficient exploitation of ultra-deep oil and gas resources.In this study,a representative strike-slip fault within a carbonate outcrop on the northwestern margin of the basin was selected as the research target.By integrating multiple analytical approaches,including field structural measurements,petrographic thin-section observations,high-pressure mercury intrusion porosimetry,and rock physics experiments,the study systematically characterizes the multi-scale heterogeneity of fault-controlled carbonate fractured-vuggy reservoirs and identifies their dominant controlling factors.The development patterns of high-quality reservoir zones are also summarized.At the macro scale,fracture distribution along the fault strike is highly uneven,with the overlap segments exhibiting the highest fracture den-sities.Within these segments,the boundary fault zones are characterized by small breccias with high roundness,indicating strong interconnectivity.Along the dip direction,fault core zones are distinguished by abundant large fractures and vugs with only minor vein filling.These zones have porosities approximately 4～6 times those of the damage zones and compressive strengths only 25%～50%as high,making them prime sites for high-quality reservoir development.Vertically,zones of high porosity and low strength alternate with sealing layers,resulting in a discrete vertical distribution of high-quality reservoirs.At the micro scale,fault cores exhibit diverse pore types,including intracrystalline pores,intercrystalline pores,semi-filled microfractures,and microvugs.In addition,they display high surface porosity,large pore aspect ratios,numerous interconnected pore nodes,and well-developed throat channels,which together contribute to their significantly higher permeability compared with the damage zones.On this basis,the Lorenz curve method is combined with the entropy weight method,which is applied for the first time to evaluate the heterogeneity of fault-controlled carbonate fractured-vuggy reservoirs.The evaluation results indicate that these reservoirs exhibit overall strong heterogeneity,with the micro scale showing a higher degree than the macro scale.This hetero-geneity is primarily governed by the coupling of fault structures and diagenetic fluid-driven dissolution-precipitation processes.Integrating these findings,three types of"sweet spot"zones are identified within the fault-controlled reservoirs:boundary fault zones in the overlap segments along the fault strike,fault core zones along the dip,and dolomitic limestone intervals in the ver-tical sequence.This study fills a gap in understanding the heterogeneity of fault-controlled carbonate fractured-vuggy reservoirs and provides theoretical support for improving the recovery efficiency of ultra-deep oil and gas resources.关键词
走滑断层/碳酸盐岩/缝洞型储层/储层非均质性/塔里木盆地Key words
strike-slip fault/carbonate rock/fracture-vuggy reservoir/reservoir heterogeneity/Tarim Basin分类
天文与地球科学引用本文复制引用
SONG Yichen,ZENG Lianbo,YAO Yingtao,TAN Xiaolin,MAO Zhe,CAO Dongsheng,GONG Fei..走滑断裂控制的碳酸盐岩缝洞型储层非均质性及其影响因素[J].石油科学通报,2025,10(6):1114-1129,16.基金项目
国家自然科学基金项目(U21B2062)资助 （U21B2062）
