鄂尔多斯盆地苏东南地区盒8段低阻气层识别  

Identification of low resistance gas reservoir of section He_8 in the southeast of Sulige,Ordos basin

作　　者：阎媛子[1] 张小莉[1] 费世祥[2,3] 石鲁豫[4] 王金成[2,3] 

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 [2]中国石油长庆油田公司勘探开发研究院,西安710018 [3]低渗透油气田勘探开发国家工程试验室,西安710018 [4]信息产业部电子综合勘察研究院,西安710054

出　　处：《地球物理学进展》2014年第3期1326-1331,共6页Progress in Geophysics

基　　金：陕西省重点学科"地质资源与地质工程"项目资助

摘　　要：上古生界二叠系下石盒子组盒8段是苏东南地区主力产气层段之一,低阻气层相对较发育,其测井响应表现为低自然伽马、高声波时差、低密度和低电阻率特征.根据常规测井处理方法,对苏东南地区50口试气井106个试气层段进行了电阻率与声波时差参数交会图分析,结果发现低阻气层的电阻率数值分布范围与邻近水层的电阻率基本相当,甚至有些含气段的电阻率比水层的电阻率低,在电阻率与声波时差参数交会图中,含气层的分布区与气水同层分布区相混,无法准确区分.另外,低阻气层在深侧向电阻率和声波时差测井曲线重叠图上基本无幅度差,这就可能造成有效含气层的漏失.针对上述这种电阻率相对较低的气层,利用非电阻率测井信号,优选声波孔隙度(ФS)、密度孔隙度(ФD)、中子孔隙度(ФN)测井资料进行重叠图处理(ФS-ФN、ФD-ФN),并增加纵波等效弹性模量差比值参数来综合识别气层.在含气层段,一般具有ФS>ФN、ФD>ФN、等效弹性模量差比值大于0.1的特征.上述综合识别含气层的方法,其判别结果不受电阻率的影响,因此在低阻气层发育的部位能够有效识别气层.经对50口试气井106个试气层段试气资料进行处理,气层识别综合符合率达95.8%.Section He8 of lower Shihezi member in Upper Paleozoic Permian is one of the most main aerogenesis reservoirs.The study show that section He8 develops more gas reservoir of low resistance relatively,where logging response features low gamma,high acoustic time,low density and low resistance.Through conventional crossplot of resistivity and acoustic time in 106 gas testing layer of 50gas-test well in the southeast of Sulige,it is found that resistance of most gas reservoirs is as the same as water layer,or even lower than them.In resistivity and acoustic time parameter crossplot,gas area and water area is so mixed that gas-bearing bed is unable to distinguish accurately.Besides,as for these gas reservoirs with relatively low resistance,there are no separation in the deep lateral resistivity and acoustic travel time curve overlapping.In addition, we can not accurately identify effective gas reservoirs because data point of low-resistance gas are in a same interval with Gas-water Layer.This paper identified gas reservoir through overlap acoustic wave time porosity logging data、density porosity logging data and neutron porosity logging data（ФS-ФN、ФD-ФN）and longitudinal wave equivalent elastic modulus difference ratio（ΔRM） method comprehensively without resistivity signal,thus,gas-bearing formation has some features such asФSФN、ФDФN andΔRM 0.1.This comprehensive identification method can identify gas reservoir effectively on account of it is not influenced by resistivity,and verified by gas testing data of 106 layers,95.8%gas reservoirs features coincide with gas texting results.

关 键 词：低阻气层 三孔隙度测井 纵波等效弹性模量差比值 苏东南 

分 类 号：P631[天文地球—地质矿产勘探]