第37卷第4期 2016年8月
文章编号：1001-3873(2016)04-043006
新疆石油地质
XINJIANG PETROLEUM GEOLOGY DOI:10.7657/XJPG20160408
Vol.37,No.4 Aug.2016
库车坳陷克深5井区巴什基奇克组应力垂向分层特征
史玲玲，唐雁刚，汪斌，王佐涛，魏红兴，周露
（中国石油塔里木油田分公司勘探开发研究院，新疆库尔勒841000）
要：通过对岩心、普通薄片、铸体薄片、扫措电镜、高压压汞等实验数据的分析，对库车勘陷克拉苏构造带克深5 摘
井区巴什基奇克组不同应力段岩石学特征、储集空间类型、物性以及孔隙结构特征展开对比分析。不同应力段岩性相似，均以方解石胶结的岩屑长石砂岩为主，但张性应力役碎颗粒以点状和点线状接触为主，过渡段碍屑颗粒以线状接触为主，压扭应力段碎屑颗粒呈定向排列；不同应力役储集层基质孔障类型存在差异，从张性应力段到压扭应力段，储集层平均孔隙度逐渐变小，平均渗透率则逐渐变大。不同应力段孔隙结构存在差异，张性应力段储集层毛细管压力曲线以I类和Ⅱ类为主，排驱压力、中值压力低，进汞饱和度高，平均孔喉半径大，喉道均匀，连通性好；而压扭应力段储集层毛细管压力曲线以IV类为主，平均孔喉半径小，孔喉分选、连通性差，排驱压力、中值压力受微裂缝影响，分市不规律；过渡投储集层特征基本介于张性应力段和压扭应力段之间。研究结果明确了克深5井区储集层垂向分层性，改变了按岩性段对储集层特征展开对比分析的传统方法。
关键词：库车地陷；克拉苏构造带；克深5并区；巴什基奇克组；应力段；垂向分层性
中图分类号：TE121.1
文献标识码：A
Characteristics of Vertical Zonation of BashijiqikeReservoir by Stress Intervals in Wellblock
Keshen-5 in Kuqa Depression, Tarim Basin
SHI Lingling,TANG Yangang,WANG Bin, WANG Zuotao, WEI Hongxing,ZHOU Lu
(Research Institute of Exploration and Development, Tarim Oilfield Company, PetroChina, Korla, Xinjiang 841000, China)
Abstract: Through analysis on the experimental data of core, common thin section, cast thin section, SEM and high-pressure mercury injec-tion, coelation and analysis on lithologicalfeatures, reservoir space types, physical properties and pore structures are carried out for each stress intervals of Bashijiqike formation in Wellblock Keshen-5 in Kelasu structural belt, Kuqa depression. The result shows that different stress intervals are similar to each other, all of which are dominated by lithic feldspar sandstone cemented by calcite, but the clastic parti-cles in extensional stress interval are mainly spot and spotline contacts and that in transitional interval are dominated by line contact, that in transpressional interval are in directional alignment; matrix pore types are different in different stress intervals, the average reservoir po-rosity gradually decreases and the average permeability becomes larger from the extensional stress interval to the transpressional interval. The pore structure varies in different stress intervals, the capillary pressure curves of the reservoirs are mainly Type I and II in the exten-sional interval, which is featured with low displacement pressure and median pressure, high mercury-intrusion saturation, large average pore-throat radius, even pore throats and good connectivity; the capillary pressure curves of the reservoirs are dominated by Type IV in the transpressional interval, which is featured with small pore-throat radius, poor porethroat sorting and connectivity, irregular distributed dis-placement and median pressures due to the influence of microcracks; the reservoirs in transitional interval have moderate features between extensional and transitional intervals. The results of the study verify the vertical zonation of Bashijiqike reservoir in Wellblock Keshen-5, and change the conventional method for lithology-based reservoir correlation and analysis.
Keywords: Kuqa depression; Kelasu structural belt; Wellblock Keshen-5; Bashijiqike formation; stress interval; vertical zonation
多数构造地质学家认为，在同一背斜内，不同部位应力分布存在明显差异，Ramsay最早对这种差异做了详细分析，其后又有很多学者探究了背斜内部的应力分布规律，通过实验模拟得出了应力分布的模型"-。研究认为，在构成背斜地层的中部发育一个基本不发生形变的中和面，位于中和面之上的地层受张应力影响大，位于中和面之下的地层则表现为压应力
特征，但未深人研究这种应力属性对储集层的影响。有学者曾探讨过中和面与油气成藏、勘探选区之间的关系3-，也有学者提出张裂型褶皱上中和面发育的扇形张裂区和下中和面发育的顺层张裂区是碳酸盐岩溶蚀储集层发育的有利区"，但所有这些有关中和面的研究都是基于理想化的理论模型，仅考虑了裂缝产状的影响。针对克拉苏构造带，文献[8]曾对克拉
收稿日期：201603-30
修订日期：2016-05-30
基金项目：国家科技重大专项(2011ZX05003-004)；中国石油科技重大专项(2014E-2101)
作者简介：史玲玲（1985-），女，潮北十堰人，工程师，沉积储层，（Tel)18799812730(Email)shill-tlm@petrochina.com.cn 万方数据