页岩储层多尺度天然裂缝表征与三维地质建模:以四川盆地平桥构造带五峰组龙马溪组页岩为例  

Characterization and 3D modeling of multiscale natural fractures in shale gas reservoir:A case study in the Pingqiao structural belt,Sichuan Basin

作　　者：乔辉 张永贵 聂海宽[1,2,3] 彭勇民[1,2,3] 张珂 苏海琨[4] QIAO Hui;ZHANG Yonggui;NIE Haikuan;PENG Yongmin;ZHANG Ke;SU Haikun(State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development,Beijing 100083,China;Sinopec Petroleum Exploration and Production Research Institute,Beijing 100083,China;Sinopec Key Laboratory of Shale Oil/Gas Exploration and Production,Beijing 100083,China;School of Energy Resources,China University of Geosciences(Beijing),Beijing 100083,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]中国石化石油勘探开发研究院,北京100083 [3]中国石化页岩油气勘探开发重点实验室,北京100083 [4]中国地质大学(北京)能源学院,北京100083

出　　处：《地学前缘》2024年第5期89-102,共14页Earth Science Frontiers

基　　金：国家自然科学基金项目(42130803,41872124);中国石化科技项目(P23132)。

摘　　要：天然裂缝是页岩储层重要的储集空间和渗流通道,查明天然裂缝类型及其空间展布特征是页岩气勘探开发的重要基础之一。基于地震、露头、岩心观察、测井和微观测试分析等资料,重点考虑裂缝对页岩气富集高产的控制作用,将页岩储层天然裂缝分为大尺度、中小尺度和微尺度3类,明确了各尺度裂缝表征与建模方法和应用效果。(1)大尺度裂缝通过叠后地震属性表征,中小尺度裂缝以岩心、成像测井和地震属性预测相结合的方法表征,微尺度裂缝通过岩心描述、扫描电镜观测等方法表征,明确了各尺度裂缝发育密度、开度、产状和充填状况等特征。(2)大尺度裂缝通过输入叠后地震属性表征参数,采用确定性建模方法建立大尺度裂缝DFN模型;中小尺度裂缝以单井成像测井解释数据为先验信息,以多信息融合的裂缝概率体为空间约束建立裂缝密度体,采用随机模拟方法建立中小尺度裂缝DFN模型;微尺度裂缝建模以微观测试分析获取的微裂缝参数为基础,井资料与TOC等主控因素属性体结合建立微裂缝密度体,采用随机模拟方法建立微裂缝DFN模型。(3)以四川盆地平桥构造带页岩气为例,开展了页岩储层不同尺度裂缝表征与三维地质建模工作,明确了不同尺度裂缝的发育位置、规模和产状特征,刻画了不同尺度裂缝的空间位置、倾角、方位角、几何尺寸、发育密度等属性特征,形成了多尺度页岩储层天然裂缝表征与建模技术,为页岩气藏数值模拟提供了较可靠的模型依据。该方法建立的平桥构造带页岩储层三维地质模型及其模拟结果与地质认识、生产数据吻合较好,对页岩气田开发具有参考价值。Natural fractures in shale reservoirs are important reservoir spaces and seepage channels.Identifying the types and spatial distribution of natural fractures is essential for shale gas exploration and development.This paper,based on seismic/outcrop data,core observation,well logging and micro-test analysis,mainly considering the effect of fractures on shale gas enrichment and high production,divides natural fractures of shale reservoirs into three scale levels:large,medium-small and micro,and clarifies the methodologies for fracture characterization and modeling at each scale level and application results.In summary:(1)large fractures were mainly characterized using stacked 3D seismic data;medium-small fractures using a combination of core,image log and seismic attributes data;and microfractures using microanalysis such as core description,high-resolution scanning electron microscope and maps analysis.Through fracture characterization,the fracture density,crack opening,dip,orientation and filling status at each scale level were determined.(2)The DFN model of large fractures was established via deterministic modeling,using the characterization parameters of post-stack seismic attributes as the input.For medium-small fractures,single-well image logs were used as prior information;a fracture probability model of multi-information fusion was established as the spatial trend;and the DFN model was established via stochastic modelling.Microfracture modeling was based on microfracture parameters obtained from micro-test analysis;microfracture density model was established by combining well data with TOC and other main control factors;and the DFN model was established via stochastic modeling.(3)Taking the shale gas reservoir in the Pingqiao tectonic zone,Sichuan Basin as an example,fracture characterization and fracture 3D geological modeling for different fracture types were carried out.The fracture initiation site,scale,orientation and occurrence characteristics were defined,and fracture attributes such as fracture loca

关 键 词：页岩气 多尺度裂缝表征 裂缝建模 四川盆地 

分 类 号：P618.130.2[天文地球—矿床学]