苏里格砂泥薄互储层缝控压裂造缝机制及穿层判别准则  

Fracture-controlled fracturing mechanism and penetration discrimination criteria for thin sand-mud interbedded reservoirs in Sulige gas field,Ordos Basin,China

作　　者：谢锦阳 侯冰[1,2,3] 何明舫 刘欣佳[4] 魏靖依 XIE Jinyang;HOU Bing;HE Mingfang;LIU Xinjia;WEI Jingyi(National Key Laboratory of Petroleum Resources and Engineering,China University of Petroleum,Beijing 102249,China;MOE Key Laboratory of Petroleum Engineering,China University of Petroleum,Beijing 102249,China;College of Petroleum Engineering,China University of Petroleum-Beijing at Karamay,Karamay 834000,China;Oil&Gas Technology Research Institute,PetroChina Changqing Oilfield Company,Xi’an 710021,China;Southwest Petroleum University,Chengdu 610500,China)

机构地区：[1]中国石油大学(北京)油气资源与工程全国重点实验室,北京102249 [2]中国石油大学(北京)石油工程教育部重点实验室,北京102249 [3]中国石油大学(北京)克拉玛依校区石油学院,新疆克拉玛依834000 [4]中国石油长庆油田公司油气工艺研究院,西安710021 [5]西南石油大学,成都610500

出　　处：《石油勘探与开发》2024年第5期1150-1159,共10页Petroleum Exploration and Development

基　　金：国家重点研发计划-中美政府间国际合作项目(2022YFE0129800);中国石油天然气集团有限公司-中国石油大学(北京)战略合作科技专项(ZLZX2020-02)。

摘　　要：针对苏里格气田二叠系盒8段砂泥薄互储层压裂施工中裂缝穿层扩展判别与压裂效果评价存在的问题,建立考虑层间非均质性的砂泥薄互储层地质力学模型,开展水力裂缝穿层扩展实验,揭示砂泥薄互储层中人工裂缝的起裂-延伸-交互-穿层机制。基于非常规裂缝模型的数值模拟,阐明了裂缝在薄互层中的垂向起裂与扩展特征,构建了裂缝穿层的判别准则与压裂效果评价方法。研究表明:层间应力差是直接影响穿层压裂裂缝形态的主要地质因素,苏里格气田层间应力差异系数(ξ_(IL))小于0.40时,裂缝可突破隔层在目标砂岩层内扩展;0.40≤ξ_(IL)<0.45时,裂缝突破隔层但无法在目标砂层内有效扩展;ξ_(IL)≥0.45时,裂缝仅在射孔储层扩展,无法实现穿层扩展。提高压裂液黏度与排量能弥补能量损耗并突破隔层限制,苏里格气田压裂施工参数控制区域内采用高黏度(50~100mPa·s)压裂液、高排量(12~18 m^(3)/min)施工条件有利于裂缝穿层。Considering the problems in the discrimination of fracture penetration and the evaluation of fracturing performance in the stimulation of thin sand-mud interbedded reservoirs in the eighth member of Shihezi Formation of Permian(He-8 Member)in the Sulige gas field,a geomechanical model of thin sand-mud interbedded reservoirs considering interlayer heterogeneity was established.The experiment of hydraulic fracture penetration was performed to reveal the mechanism of initiation–extension–interaction–penetration of hydraulic fractures in the thin sand-mud interbedded reservoirs.The unconventional fracture model was used to clarify the vertical initiation and extension characteristics of fractures in thin interbedded reservoirs through numerical simulation.The fracture penetration discrimination criterion and the fracturing performance evaluation method were developed.The results show that the interlayer stress difference is the main geological factor that directly affects the fracture morphology during hydraulic fracturing.When the interlayer stress difference coefficient is less than 0.4 in the Sulige gas field,the fractures can penetrate the barrier and extend in the target sandstone layer.When the interlayer stress difference coefficient is not less than 0.4 and less than 0.45,the factures can penetrate the barrier but cannot extend in the target sandstone layers.When the interlayer stress difference coefficient is greater than 0.45,the fractures only extend in the perforated reservoir,but not penetrate the layers.Increasing the viscosity and pump rates of the fracturing fluid can compensate for the energy loss and break through the barrier limit.The injection of high viscosity(50–100 mPa·s)fracturing fluid at high pump rates(12–18 m^(3)/min)is conducive to fracture penetration in the thin sand-mud interbedded reservoirs in the Sulige gas field.

关 键 词：砂泥薄互储层 穿层压裂 压裂模拟实验 数值模拟 穿层判别准则 压裂效果评价 

分 类 号：TE357[石油与天然气工程—油气田开发工程]