火成岩蚀变层段的有效储层识别及孔隙度定量表征——以滨南油田沙四段上亚段火成岩为例  

Identification of effective reservoir and quantitative evaluation of porosity of altered igneous rock:A case study of igneous rock in the upper fourth member of Shahejie Formation in Binnan Oilfield

作　　者：王敏[1] 王永诗[2] 田淼 傅爱兵[1] 朱家俊[1] 张顺[1] 余光华[1] WANG Min;WANG Yongshi;TIAN Miao;FU Aibing;ZHU Jiajun;ZHANG Shun;YU Guanghua(Exploration and Development Research Institute,Shengli Oilfield Company,SINOPEC,Dongying City,Shandong Province,257015,China;Shengli Oilfield Company,SINOPEC,Dongying City,Shandong Province,257001,China;College of Geosciences,China University of Petroleum（Beijing）,Beijing City,102249,China)

机构地区：[1]中国石化胜利油田分公司勘探开发研究院,山东东营257015 [2]中国石化胜利油田分公司,山东东营257001 [3]中国石油大学(北京)地球科学学院,北京102249

出　　处：《油气地质与采收率》2018年第4期22-27,共6页Petroleum Geology and Recovery Efficiency

基　　金：国家科技重大专项"渤海湾盆地精细勘探关键技术"(2016ZX05006-003);胜利油田博士后基金项目"东营凹陷砂砾岩含油饱和度解释模型研究"(YKB1604)

摘　　要：火成岩地层因蚀变程度不同常引起测井曲线的响应异常,特别是出现中子测井值异常变大的假象,制约了油气勘探工作中对有效储集空间的识别及定量评价。基于中子测井原理,结合薄片镜下观察结果,发现高温下岩石矿物蚀变产生的含大量结晶水的绿泥石和沸石是导致高中子测井值的主要原因。当中子测井值高于30%且自然电位曲线无明显异常时,一般为非储层。在蚀变严重情况下,不宜采用与中子测井相关的孔隙度计算模型进行储层孔隙度定量表征,采用MOSTAFA模型计算火成岩蚀变层段的储层孔隙度,该模型中的岩石骨架声波时差可以采用测井曲线交会图分析法确定。以滨南油田沙四段上亚段火成岩为例,其岩石骨架声波时差的取值为167μs/m,岩性指数为1.706,利用MOSTAFA模型计算其平均孔隙度为15%。通过模型处理并与岩心孔隙度分析对比,证实若岩石骨架参数选取合适,适用于碳酸盐岩储层的MOSTAFA模型在火成岩储层孔隙度评价中也同样具有较高的精度,可用于滨南油田蚀变火成岩储层物性的定量评价。Igneous rock often causes the abnormal response of well logging due to hydrothermal alteration,especially the false appearance of high neutron logging value,which restricts the identification and quantitative evaluation of effective storage space in oil and gas exploration. Based on the principle of neutron logging,combined with microscopic observation, it is pointed out that the hydrothermal altered minerals such as chlorite and zeolite which contain a large amount of crystal water is the main cause of high neutron value. When the neutron logging value is over 30% and no obvious anomaly existsin natural potential curve,basically it is invalid reservoir. It is suggested that the porosity calculation model associated withneutron logging should be substituted by the MOSTAFA model to quantitatively characterize reservoir porosity in case of se？rious alteration. The rock acoustic in the model could be determined by the method of the cross-plot of logging curves. Tak？ing the igneous reservoir at the upper fourth member of Shahejie Formation in Binnan Oilfield as an xample,the skeletonacoustic value is 167 μs/m and the lithology index is 1.706,and the average porosity is 15% calculated by MOSTAFA mod？el. Through comparison between the porosity calculated by the model processing and the measured porosity of cores,it isconfirmed that the model of MOSTAFA,which is suitable for carbonate reservoir,is good for evaluation of the porosity of ig？neous rock when an appropriate rock skeleton parameter is used,and it could be used to quantitatively evaluate physicalproperties of altered igneous rock in Binnan Oilfield.

关 键 词：中子测井 火成岩 粘土矿物 蚀变 有效储层 孔隙度模型 

分 类 号：TE122.2[石油与天然气工程—油气勘探]