一种新的储层孔隙成因类型——石英溶解型次生孔隙  

A New Type of Secondary Porosity--Quartz Dissolution Porosity

作　　者：邱隆伟[1] 姜在兴[1] 陈文学[2] 李晓红 熊志东[2] 

机构地区：[1]石油大学(华东)资源学院,山东东营257062 [2]河南石油勘探局,河南南阳473000 [3]中国石油华北油田公司勘探开发研究院,河北任丘062552

出　　处：《沉积学报》2002年第4期621-627,共7页Acta Sedimentologica Sinica

基　　金：国家重点基础研究发展规划 (973)项目 (批准号 :G1 9990 7550 7)资助

摘　　要：石英作为碎屑岩储层中的一种难溶组分 ,普遍认为它和次生孔隙的形成关系不十分密切。研究认为泌阳凹陷核桃园组储层中的碎屑石英颗粒存在明显的溶解现象 ,并形成以石英直接溶解型孔隙为主的储集空间特征。石英颗粒被溶解的部分在薄片中所占的范围为 2 %～ 7%者常见 ,高者达 8%以上 ,在总孔隙中所占的相对含量也多数在10 %～ 35 %之间 ,早成岩B期是其最主要形成期。石英溶解型次生孔隙的大量存在为碎屑岩储层中SiO2As one of the most stable petrogenetic minerals in clastic reservoir, quartz is generally considered to be indissoluble to directly form secondary porosity during diagenesis, and the dissolved rim of quartz in reservoir has been thought to be the result of dissolution of cements that substituted quartz formerly. In this study, quartz was found to have been dissolved directly in the reservoir of Hetaoyuan formation in Biyang depression, and form a new genetic type of porosity, i.e. quartz dissolution porosity, which is one of the most important porosity types in reservoir in the studied area. The dissolution of quartz reaches 2%～7%, and sometimes up to more than 8% of microscopic porosity in the reservoir rock,, which accounts for 10%～35% of total porosity. Several lines of microscopic evidence for quartz dissolution are listed as follows: (1) Partial dissolution of clastic quartz. Quartz was dissolved partially to form irregularly rim, isolated grains, intercrystalline pores, sometimes quartz grains can be dissolved partly, and even completely, and result in the formation of stretched pores. (2) Dissolution of quartz develops along contact seam, the opening of contact seams can form irregular pore throat, which couldnot be the result of dissolution of quartz substituting cements. (3) Partial dissolution of quartzose detritus, the erosion of the detritus is obvious, and sometimes it can form honeycombed micropores. (4) Shape of carbonate components, both carbonate cements and debritus do not show much dissolution in reservoir rocks of the studied area, however, adjacent quartz grains were dissolved obviously, this further reveals that quartz was dissolved directly. Quartz dissolution in the studied area is the result of sedimentary environment, diagenesis, and evolution of formation water. Biyang depression was an arid to semi arid subtropical enclosed fault trough lake during deposition, and the depositional environment of which was an alkaline lake. The original formation water of the reserv

关 键 词：储层 孔隙类型 石英溶解孔隙 成岩作用 泌阳凹陷 碎屑岩 

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