摘要
利用大量砂岩样品的普通薄片、铸体薄片、阴极发光、物性分析等资料,研究了库车前陆冲断带白垩系中-深层砂岩储层的物性、孔喉类型和成岩作用特征,并通过开展各种成岩参数（压实减孔量、胶结减孔量、粒间体积、碳酸盐胶结物含量、溶蚀孔面孔率）和储层物性的相关分析,结合构造演化,认为中层砂岩储层物性主要受碳酸盐胶结作用和溶蚀作用控制,深层砂岩储层物性主要受晚期压实作用、胶结作用和裂缝共同控制;构造挤压是控制晚期压实和物性变化的主要原因.研究结果表明：从中层到深层砂岩储层,孔隙度和渗透率的相关系数从0.79降为0.35,相关曲线斜率值从0.24降为0.09,深层砂岩基质渗透率基本在0.01～0.10mD之间;孔喉类型由缩颈型、点状演变为片状、弯片状喉道为主;中层砂岩压实弱,碳酸盐主要胶结后的晚期压实发育不明显;深层砂岩压实强,碳酸盐胶结之后仍发育显著的晚期压实作用;而中-深层砂岩的胶结程度差别不大,溶蚀程度与残余粒间孔和裂缝发育有关.依据储层控制因素可知,深层储层的南部,埋深更大,孔隙却相对发育.
According to conventional thin section,cast thin section,cathodoluminescence and physical property analysis of numerous sandstone samples,the physical properties,pore throat types and diagenesis characteristics of the Cretaceous middle and deep buried sandstone reservoirs in Kuqa foreland thrust belt were studied in this paper.Furthermore,correlations between various diagenetic parameters（compactional porosity loss,cementational porosity loss,intergranular volume,carbonate cement contents,areal porosity of secondary pores）and reser-voir property were also investigated.Combined with tectonic evolution,it is considered that the physical property of middle buried reservoirs was mainly controlled by carbonate cementation and dissolution,while that of deep buried reservoirs was dominated by late compaction,cementation and fractures.Tectonic compression is the major factor triggering reservoir property changes and the late compaction.Research results show that from middle to deep reservoirs,the correlation coefficient between porosity and permeability drops from 0.79 to 0.35,and the correlation curve gradient decreases from 0.24 to 0.09.The matrix permeability in deep buried sandstone reservoirs basically falls within the range of 0.01—0.10 mD.The major pore throat types contains necking throat,punctual throat evolving to the laminated throat and curved lamellar throat.The middle buried sandstone reservoirs are weakly compacted and the compaction is not well developed after carbonate cementation.By comparison,the deep buried reservoirs go through intensive compaction and the compaction continues after carbonate cementation.The cementation degree between middle and deep reservoirs has little difference,and the dissolution degree is related to the volume of residual intergranular pores and fractures.Based on the reservoir controlling factors,it can be concluded that the southern deep buried reservoirs is deeper,but the porosity there develops better.
出处
《中国矿业大学学报》
EI
CAS
CSCD
北大核心
2016年第6期1184-1192,共9页
Journal of China University of Mining & Technology
基金
国家科技重大专项(2011ZX05003-004)
国家重点基础研究发展计划(973)项目(2011CB201104)
国家自然科学基金项目(41302108)
关键词
孔隙度
成岩作用
深埋砂岩储层
白垩系
库车坳陷
porosity
diagenesis
deeply buried sandstone reservoir
Cretaceous
Kuqa depression
