柴达木盆地昆北断阶带底砾岩储层特征研究  

Study on Characteristics of Basal Conglomerate Reservoir in North-Kunlun Faults Zone, Qaidam Basin

作　　者：崔俊[1] 郑永仙[1] 陈登钱[1] 沈晓双[1] 黄耀[1] 

机构地区：[1]中国石油青海油田公司勘探开发研究院,甘肃省敦煌市736202

出　　处：《中国石油勘探》2013年第3期26-33,共8页China Petroleum Exploration

摘　　要：在区域地质背景分析的基础上,研究认为昆北断阶带底砾岩为风化残积层,岩石学分析认为昆北断阶带基岩为二长花岗岩,基岩之上为半风化壳,厚度约0.5m,岩石破裂缝发育,半风化壳以上为昆北断阶带底砾岩,厚度30～60m,是昆北断阶带的主要含油层系,常规孔渗分析,孔隙度平均值为12.37%,渗透率平均值为69.87mD,属低孔中渗储层。储层孔隙类型以颗粒破裂缝、颗粒溶孔、粒间溶孔等次生孔隙为主。由于研究区储层岩石成岩作用弱,粒度粗,岩石较疏松,常规孔渗分析数据不能真实反映储层岩石物性,经对比发现常规孔隙度比煤油法孔隙度大25%,常规渗透率比核磁渗透率大80%,因此针对研究区底砾岩储层采用合理的测试方法求取储层物性数据,更好地指导研究区勘探开发显得尤为重要。Based on regional geological background, it is believed that the basal conglomerate in North-Kunlun Faults Zone is weathering eluvium. Petrographic analysis shows that the bedrock in the zone is monzogranite. Above this is semi-weathered crust, which is about 0.5m deep. Here develops rock breaking fracture. Above the semi-weathered crust is the basal conglomerate, which is 30-60m deep. This is the main hydrocarbon reservoir assemblage in North-Kunlun Faults Zone. Conventional porosity and permeability analysis shows that the average porosity value is 12.37% and the average permeability value is 69.87mD, belonging to low-porosity and mid-permeability reservoir. Reservoir pore is dominated by secondary pore including particle breaking fracture, particle dissolved pore, and intergranular dissolved pore, etc. Rock in the reservoir is unconsolidated for its weak diagenesis and big grain size, so conventional porosity and permeability analysis could not actually reflect rock property. Comparison shows that the porosity determined by conventional analysis is 25% higher than using kerosene method, and the permeability determined by conventional analysis is 80% higher than using NMR method. Therefore, using rational testing method to get reservoir property targeted at the basal conglomerate becomes more and more important to guide exploration and development in studied area.

关 键 词：柴达木 昆北断阶带 底砾岩 储层特征 

分 类 号：TE112.2[石油与天然气工程—油气勘探]