鄂尔多斯盆地延长组砂岩中绿泥石膜的赋存状态及成因  

Occurrences and Origin of Chlorite Films in the Yanchang Formation Sandstones,Ordos Basin

作　　者：周晓峰[1,2] 焦淑静 于均民 ZHOU Xiao-feng;JIAO Shu-jing;YU Jun-min(College of Petroleum Engineering, MOE Key Laboratory of Petroleum Engineering, China University of Petroleum, Beijing 102249, China;State Key Laboratory of Petroleum Resources and Engineers ,Beijing 102249, China)

机构地区：[1]中国石油大学(北京)石油工程学院石油工程教育部重点实验室,北京102249 [2]油气资源与工程国家重点实验室,北京102249

出　　处：《矿物岩石地球化学通报》2017年第5期834-842,共9页Bulletin of Mineralogy, Petrology and Geochemistry

基　　金：国家科技重大专项(2011ZX05013-006);中国石油大学(北京)科研基金项目(KYJJ2012-02-46)

摘　　要：通过铸体薄片和带有能谱仪的扫描电镜对鄂尔多斯盆地延长组绿泥石膜进行观察与测试,研究其赋存状态、成因与物性的关系。结果表明,绿泥石膜的赋存状态可分为3类5亚类,Ⅰ类绿泥石膜为渗滤黏土转化,Ⅱ1和Ⅱ2亚类绿泥石膜为富铁镁物质溶蚀再结晶,Ⅱ3和Ⅲ2亚类绿泥石膜为富铁镁物质与骨架颗粒溶蚀再结晶,Ⅲ1亚类绿泥石膜为同沉积泥质转化和富铁镁物质溶蚀再结晶形成;绿泥石膜胶结是一种破坏性成岩作用,其充填孔隙、堵塞喉道,使砂岩粒间孔隙的一部分变成微孔隙,导致孔隙度、渗透率以及可动流体饱和度降低,而石英胶结物少是因为孔隙中硅质流体含量不足以沉淀大量自生石英颗粒,并非绿泥石膜抑制石英胶结。In order to study the occurrences and origin of the chlorite films,casting slice and scanning electron microscope analysis were performed on chlorite films of the Yanchang Formation sandstone in Ordos Basin. The chlorite film can be divided into three types and five subtypes on the basis of their occurrences. The type-I was formed from the transformation of the infiltration clay mineral. The subtype-Ⅱ1 and-Ⅱ2 originated from the dissolution and recrystallization of iron-rich and magnesium-rich fragments,respectively. The subtype-Ⅱ3 and-Ⅲ2 resulted from the dissolution and recrystallization of the iron-rich and magnesium-rich fragments and skeletons, respectively. The subtype-Ⅲ1 was generated from the transformation of the synsedimentary mud and dissolution and recrystallization of the Fe-Mg-rich fragments. The content of the quartz cement in the sandstones is very low because of the insufficient silica fluid in the intergranular pore. The cementation of chlorite films is a destructive diagenesis,which can fill the pore,block the pore,decrease the porosity,permeability and mobile fluid saturation in the sandstones.

关 键 词：鄂尔多斯盆地 延长组 绿泥石膜 赋存状态 成因模式 破坏性成岩作用 

分 类 号：P618.13[天文地球—矿床学]