克拉通盆地区域裂缝带的识别与分布研究——以鄂尔多斯盆地南部镇泾地区延长组长8段为例  

Identification and distribution of regional fractures zone in Craton Basin——Take the Chang8 Member in Yanchang Formation in Zhen-Jing Area,southern Ordos Basin as an example

作　　者：刘志远[1] LIU Zhiyuan(SINOPEC,Petroleum Exploration and Production Institute,Beijing 100083,China)

机构地区：[1]中国石油化工股份有限公司石油勘探开发研究院,北京100083

出　　处：《非常规油气》2022年第3期11-20,共10页Unconventional Oil & Gas

基　　金：中石化重点攻关项目“致密超致密砂岩气层识别及选层评价”(20039-2)。

摘　　要：为了搞清克拉通盆地区域裂缝分布特征,针对裂缝带识别与横向延展性判断问题,以鄂尔多斯盆地南部镇泾地区三叠系延长组长8段为例,采用测井综合裂缝指数进行单井裂缝识别,依据裂缝优势走向,开展裂缝井间对比以识别区域裂缝带,并进一步分析裂缝带横向发育特征,明确裂缝带对油气产能的影响。结果表明鄂南镇泾地区裂缝主要为高角缝,在水平井中表现为电阻率降低、声波时差增大等明显响应特征,采用综合裂缝敏感指示算法可有效识别;裂缝横向上呈束状发育,产状稳定,走向以北东东—南西西向为主,横向延伸形成长达0.6~3.0 km裂缝带,成组发育,组距1~2 km;裂缝带纵向穿透性强,能够有效沟通烃源岩与相邻致密砂岩储层;裂缝带不但是油气聚集的重要场所,也是油气运移的有利通道,对鄂南致密砂岩储层油气富集产出起到关键作用。该成果认识,对克拉通盆地区域裂缝带分布规律认识、油气藏发育特征研究、甜点储层识别以及深化勘探开发具有一定指导意义。In order to understand the regional fracture distribution characteristics of Craton Basin,aiming at the identification of fracture zone and the judgment of transverse ductility,taking the Chang8 Member of Triassic Yanchang Formation in Zhen-Jing Area in the south of Ordos Basin as an example,the logging comprehensive fracture index is used for single well fracture identification,and the fracture inter well comparison is carried out to identify the regional fracture zone according to the dominant trend of fracture,The lateral development characteristics of fracture zone are further analyzed to clarify the impact of fracture zone on oil and gas productivity.The results show that the fractures in Zhen-Jing Area of the southern Ordos are mainly high angle fractures,which show obvious response characteristics such as reduced resistivity and increased acoustic time difference in horizontal wells.The comprehensive fracture sensitive indication algorithm can be effectively identified.The fractures are developed in bundles laterally,the occurrence is stable,the strike is mainly NE-SW,extending laterally to form a fracture zone of 0.6~3.0 km,which is developed in groups,the group spacing is 1~2 km,and the fracture zone has strong longitudinal penetration,which can effectively communicate the source rock with the adjacent tight sandstone reservoir.The fracture zone is not only an important place for oil and gas accumulation,but also a favorable channel for oil and gas migration,which plays a key role in the enrichment and production of oil and gas in the tight sandstone reservoir in the southern Ordos.The above achievements have certain guiding significance for understanding the distribution law of regional fracture zones in Craton Basin,studying the development characteristics of oil and gas reservoirs,identifying sweet reservoirs and deepening exploration and development.

关 键 词：区域裂缝带 裂缝识别 井间裂缝对比 致密砂岩 鄂尔多斯盆地 镇泾地区 

分 类 号：TE122.2[石油与天然气工程—油气勘探]