库车坳陷西部古近系-白垩系沉积储层特征分析

库车坳陷西部古近系-白垩系主要发育古近系库姆格列木群底砂(砾)岩段、白垩系巴什基奇克组和舒善河组3套储层,这3套储层与其上覆盖层组成良好的储盖组合,目前在这几套储层中均已获得高产工业油气流,油气勘探前景广阔。研究区有利储层主要为扇三角洲前缘及辫状三角洲平原-前缘沉积的含砾砂岩、中细砂岩和粉砂岩,孔隙度大于8%的有利储层在克拉苏-大北构造带、西秋立塔格-却勒区带及其南部地区、温宿凸起北部及东缘地区广泛分布,储层储集性能主要受快速深埋、沉积相、构造作用控制。认为勘探中应尽量避开褶皱强烈的地层重复地区、高挤压应力集中区和盆地粗碎屑边缘相带等。

ANALYSIS OF CHARACTERISTICS OF SEDIMENTARY RESERVOIR BETWEEN CRETACEOUS AND PALAEOGENE IN THE WESTERN PART OF THE KUQA DEPRESSION

The clastic reservoirs mainly developed on the bottom of Palaeogene Kumugeliemu group, the Cretaceous Bashijiqike formation and Shushanhe formation, and the three sedimentary reservoirs and their overlying formation consist of good reservoir-cap assemblages. At present, industrial oil-gas streams are obtained from the three reservoirs, and the exploration potential is good. The excellent reservoirs are the fan delta front and braided delta plain-front formations which are made of Conglomeratic sand, middle-fine sandstone and siltstone, where there effective reservoirs with porosity higher than 8 % widely distribute in the Kelasu-dabei structural belt, the western and southern Qiulitage-Quele structural belt and the northern and eastern Wenshu heave. The reservoir property is controlled by quickly deep burying, sedimentary facies and structural movement. The region with strong folding or repeated strata, high compression stress and coarse elastic marginal facies is not an ideal location for exploration.