低级别逆断层对页岩气富集高产影响研究——以四川盆地东南缘南川地区平桥东1断层为例  

Influence of lower-level reverse faults on shale gas enrichment and high yield:A case study of Pingqiao Dong-1 Fault in Nanchuan area,southeast margin of Sichuan Basin

作　　者：高全芳 张培先 关琳琳[1,2] 李彦婧 倪锋 GAO Quanfang;ZHANG Peixian;GUAN Linlin;LI Yanjing;NI Feng(State Key Laboratory of Shale Oil and Gas Enrichment Mechanism and Efficient Development,Beijing 100083,China;Research Institute of Exploration and Development,Sinopec East China Oil&Gas Company,Nanjing,Jiangsu 210019,China)

机构地区：[1]页岩油气富集机理与高效开发全国重点实验室,北京100083 [2]中国石化华东油气分公司勘探开发研究院,江苏南京210019

出　　处：《油气藏评价与开发》2024年第3期458-467,共10页Petroleum Reservoir Evaluation and Development

基　　金：国家重大科技专项“彭水地区常压页岩气勘探开发示范工程”(2016ZX05061);中国石化科技部项目“渝东南地区浅层页岩气勘探开发关键技术”(P24115);中国石化科技部项目“四川盆地及周缘资源评价”(P23221)

摘　　要：南川地区位于四川盆地东南缘的复杂构造区,低级别逆断层较为发育,基于区域构造分析及构造精细解释开展逆断层形成机制及分布规律研究,并结合地震属性预测、钻井、压裂及试气试采等资料,以平桥东1断层为例,开展了低级别逆断层对页岩储集性能、保存条件、压裂改造影响的分析,以揭示其对页岩气富集高产的影响。研究表明:南川地区低级别逆断层的形成主要受控于燕山中期—燕山晚期的江南—雪峰隆起的陆内造山作用的远程传导以及区域挤压应力场的变化影响,其走向整体呈北东向、北北东向,断层规模较小。平桥东1断层伴生大量天然裂缝,有效改善了储集性能,且未破坏保存条件,有利于页岩气富集成藏、地应力释放及压裂改造形成复杂缝网,实现单井高产。低级别断层附近可作为目标优选和井位部署的有利区,有效指导了复杂构造区页岩气勘探开发。Located in the complex structural area of the southeastern margin of Sichuan Basin,Nanchuan area is characterized by the prevalent development of low-level reverse faults.This study employs a combination of regional structural analysis and fine structural interpretation to explore the formation mechanisms and distribution patterns of these reverse faults.Utilizing seismic fracture-attribute prediction,drilling,fracturing,and gas test data,this research analyzes the impact of low-level reverse faults on shale reservoir performance,preservation conditions,and fracturing transformation,with a specific focus on the Pingqiao Dong-1 Fault.Findings indicate that the formation of lower-level reverse faults in the Nanchuan area,predominantly oriented NE and NNE with a small scale,was mainly influenced by the long-distance transmission of intracontinental orogeny from the Jiangnan-Xuefeng uplift and changes in the regional compressional tectonic stress field during the Middle to Late Yanshan periods.The Pingqiao Dong-1 Fault notably enhances reservoir properties through the presence of abundant natural fractures without compromising the preservation conditions.This fault alignment facilitates hydraulic fracturing processes to form complex fracture networks,leading to high production from individual wells.Further,exploration and development practices demonstrate that shale gas wells located within 400 meters of lower-level reverse faults achieve high yields,identifying these vicinities as favorable zones for target optimization and well deployment.The results from this study offer valuable insights and guidance for the exploration and development of shale gas in structurally complex regions.

关 键 词：南川地区 平桥东1断层 低级别逆断层 页岩气 富集高产 

分 类 号：TE122[石油与天然气工程—油气勘探]