鄂尔多斯盆地上古生界砂岩中自生高岭石成因类型及其对储层的影响  

Influence on Reservoirs and Genetic Type of Authigenic Kaolinite in Upper Paleozoic Sandstone of Ordos Basin

作　　者：石小虎[1] 杨奕华[1] 南珺祥[1] 

机构地区：[1]中国石油长庆油田分公司勘探开发研究院

出　　处：《低渗透油气田》2006年第1期29-32,共4页

摘　　要：自生粘土矿物成因是碎屑岩储层成岩作用的难点与热点。高岭石作为鄂尔多斯盆地上古生界砂岩储层主要粘土矿物之一，通过显微和扫描电镜鉴定，并结合电子探针成分分析，依据自生高岭石成因可分为两种类型，即孔隙析出型和蚀变型高岭石。这些自生高岭石是含油气酸性流体与砂岩中碱性长石发生水岩反应的产物。储层中长石溶蚀后生成的高岭石，在中一粗粒砂岩中，原生粒间孔发育，含油气流体活动强度大、渗流速度较高，高岭石易于迁移到别处，储层物性得到改善，反之高岭石原地沉淀，储层物性变差。The genesis of the authigenic clay mineral is considered as one of the difficulties and hotspots. The kaolinite, as one of the main clay minerals of sandstone reservoirs in Ordos basin, is divided into two types, that is, precipitated-from-pores type and altered type, according to the genesis of authigenic kaolinite, and through microscope, SEM, and composition analysis by electron probe. The authigenic kaolinite is products of water-rock reaction between petroleum-bearing sour fluid and alkaline feldspar in the sandstone. The feldspar in reservoin was corroded to form the kaolinite. Primary intergranular pores were devdoped in mid-coarse grain sandstone. The hydrocarbon fluid is highly active with a high percolation vdocity. It makes the kaolinite easily to be moved to other places. Therefore the physical properties of reservoirs were improved. On the contrary, kaolinite was precipitated in-situ and the reservoir quality became worse.

关 键 词：鄂尔多斯盆地 上古生界 高岭石 溶蚀作用 

分 类 号：P618.130.2[天文地球—矿床学] P618.130.1[天文地球—地质学]