鄂尔多斯盆地定边—志丹地区延长组致密砂岩储层裂缝测井识别  

Logging identification method for fractures in tight sandstone reservoirs of Yanchang Formation in Dingbian-Zhidan area,Ordos Basin

作　　者：钟高润[1] 张小莉[1] 杨振 卢俊辉 赵希 王晓琳 ZHONG GaoRun;ZHANG XiaoLi;YANG Zhen;LU JunHui;ZHAO Xi;WANG XiaoLin(State Key Laboratory for Continental Dynamics,Department of Geology,Northwest University,Xi\an 710069,Chian)

机构地区：[1]西北大学大陆动力学国家重点实验室,西北大学地质学系,西安710069

出　　处：《地球物理学进展》2021年第4期1669-1675,共7页Progress in Geophysics

基　　金：国家重大科技专项“柴达木复杂构造区油气成藏关键勘探技术与新领域目标优选”(2016ZX05003-006);国家高科技研究发展计划(“863”计划)“二氧化碳地质封存关键技术”(2012AA050103)联合资助。

摘　　要：裂缝是影响致密砂岩储层高产及稳产的关键,目前,对致密砂岩储层裂缝定性识别与表征仍很困难.在对致密砂岩裂缝研究现状系统调研的基础上,以鄂尔多斯盆地定边—志丹地区延长组岩芯、成像测井、常规测井资料为基础,分析裂缝发育类型,利用岩芯和成像测井标定,明确裂缝测井响应特征,优选对裂缝响应敏感的测井参数,建立有效的裂缝测井识别方法.研究表明:(1)定边—志丹地区裂缝按成因分有天然构造裂缝、钻具诱导裂缝、井眼崩塌裂缝、应力释放裂缝,按角度大小分为垂直裂缝、高角度裂缝、低角度裂缝、水平裂缝;(2)常规测井系列中对裂缝反映灵敏的参数依次为微电极、八侧向电阻率、声波时差、自然伽马、自然电位、双感应电阻率、井径;(3)通过裂缝敏感测井参数,分别构建曲线变化幅度参数(FIA)、曲线变化率参数(FIG),进而构建裂缝识别综合指数(FFA),结合电阻率侵入指数,在此基础上,采用人工判识方法,排除泥质条带、钙质砂岩等岩性变化所造成的影响,最终确定裂缝可能发育段,裂缝综合识别率为80.6%,能够对致密砂岩储层裂缝进行识别和预测.Fractures are the key to high and stable production in tight sandstone reservoirs.At present,it is still difficult to qualitatively identify fractures in tight sandstone reservoirs.On the basis of investigation and research,fracture development types are analyzed according to core,imaging logging and conventional logging data.Using core and imaging logging calibration,the corresponding characteristics of fracture logging are clarified,and the logging parameters sensitive to fracture response are optimized to establish an effective fracture logging identification method in Dingbian-Zhidan area,Ordos basin.The results show that:(1)According to the origin of the fractures,there are natural structure fractures,drilling tool induced fractures,borehole collapse fractures,stress release fractures,high Angle fractures,low Angle fractures,and horizontal fractures.(2)In the conventional logging series,the parameters sensitive to fractures are Microelectrode(RLML and RNML),Laterolog8(LL8),Acoustic transit time(AC),Natural gamma(GR),Spontaneous Potential(SP),Double induction(RILD and RILM),and Borehole diameter(CAL).(3)Through crack sensitive logging parameters,build curve variation parameters(FIA),the change rate curve(FIG),and then a comprehensive index for fracture identification(FFA),combining resistivity invasion index,on this basis,the method of artificial or exclude argillaceous stripe,calcareous sandstone lithology change,the impact of the final fracture possible development section,the comprehensive fracture recognition rate is 80.6%.The method can be used to recognize or predict fractures in the tight sandstone reservoir.

关 键 词：裂缝 测井识别 致密砂岩 定边—志丹地区 鄂尔多斯盆地 

分 类 号：P631[天文地球—地质矿产勘探]