摘要
综合采用岩心描述、薄片观察及成像测井解释等方法,多尺度定量表征了库车坳陷大北气藏白垩系巴什基奇克组裂缝特征,对裂缝的线密度、规模、视倾角等参数特征及其在平面上和剖面上的变化规律进行了系统研究。在垂向上,裂缝的线密度上低、下高,规模上大、下小,视倾角同样上大、下小;在平面上,裂缝线密度翼部高、核部低,视倾角翼部低、核部高。研究区发育四大类组合方式的构造裂缝,包括雁列型、伴生型、错断型和破碎带型,各类构造裂缝在断背斜尺度上的分布存在差异。其中,前3种类型在垂向上主要分布在目的层中上部,平面上则位于断背斜核部;第4种一般纵向上位于目的层下部,平面上位于背斜翼部等。不同规模的构造裂缝对储层均有沟通孔隙、增强溶蚀和改善物性的作用,进一步改善了储层产能。在4类裂缝组合方式中,第4种组合对储层的改善较弱;而前3种组合的储层物性则相对好,是相对有利区。
By means of core description,thin slice observation and imaging logging interpretation,structural fractures of ultra-deep reservoir-Cretaceous Bashijiqike Formation in Dabei Gasfields of Kuqa Depression,Tarim Basin are characterized quantitatively in different scales.Linear density,scale,apparent dip and other features of tectonic fractures as well as their change regularity on the space are counted and analyzed.From top to bottom,linear density of fractures increases gradually,while scale and apparent dip of fractures tends to decrease.The fracture apparent dip is lower and fracture linear density is much higher in wings of fault anticline than that in core of fault anticline.Four kinds of combination modes of tectonic fractures are classified,such as en-echelon pattern,associated pattern,fault pattern and crushed zone pattern,and the distribution of which in the fault anticline is concluded.The crushed zone pattern fractures are mainly developed in the bottom and wings of a fault anticline,where extrusion stress is powerful.While the other three patterns of fracture combination are primarily distributed around core of a fault anticline,and in middle-upper part of a fault anticline.Tectonic fractures in different scale can communicate pores,enhance dissolution,improve reservoir quality and promote reservoir productivity.Fractures with different combination mode play different role on reservoirs.Fractures in reticular combination which develop in crushed zone play a weaker role on reservoirs than other combination mode.How fracture parameters and combination mode impact on reservoir productivity is summarized.Fractures with large scale and en-echelon pattern can well communicate hydrocarbon,which is an important direction to find productive industrial gas flow.
作者
史超群
王佐涛
朱文慧
蒋俊
张慧芳
周思宇
娄洪
左小军
李刚
王振鸿
SHI Chao-qun;WANG Zuo-tao;ZHU Wen-hui;JIANG Jun;ZHANG Hui-fang;ZHOU Si-yu;LOU Hong;ZUO Xiao-jun;LI Gang;WANG Zhen-hong(Exploration and Developmenl Research Institute of Tarim Oilfield Company,CNPC,Korla 841000,China;Resource Exploration Division,Tarim Oilfield Company,CNPC,Korla 841000,China)
出处
《天然气地球科学》
EI
CAS
CSCD
北大核心
2020年第12期1687-1699,共13页
Natural Gas Geoscience
基金
国家科技重大专项“塔里木前陆盆地油气成藏、关键勘探技术与新领域目标优选”(编号:2016ZX05003-004)资助。
关键词
库车坳陷
克拉苏构造带
白垩系巴什基奇克组
构造裂缝
超深储层
裂缝组合
Kuqa Depression
Kelasu Tectonic Belt
Cretaceous Bashijiqike Formation
Tectonic fracture
Ultra-deep reservoir
Fracture combination