摘要
对川中地区钻井岩心样品中黏土矿物进行X-衍射分析、岩心铸体测试及电镜扫描微观图像观察,进而对研究区黏土矿物绿泥石的微观特征及其在碎屑岩中的各种赋存状态、成因以及与储集层发育的关系进行研究。川中地区绿泥石主要为三八面体铁—镁过渡型偏富铁绿泥石,呈包膜或孔隙衬里出现,多形成于中成岩阶段,并与富铁沉积环境有关。研究区绿泥石含量与孔隙度、渗透率有一定的正相关性。绿泥石在储集层中的分布和赋存状态对储集层孔渗性有重要的影响,环边绿泥石的沉淀及其在成岩过程中的再生长不仅提高了岩石的机械强度和抗压实能力,而且降低了自生石英与孔隙水的接触面积从而抑制石英的次生加大,使砂岩中的孔隙得以保存。
On the basis of X-ray diffraction of clay minerals,analysis of resin-cast thin sections of cores,and scanning electron microscope(SEM) observation of samples in central Sichuan Basin,this paper studies the microscopic characteristics and occurrences of chlorite and the relationship between its genesis and reservoir development.The chlorite in central Sichuan Basin is mainly trioctahedron ferrum-magnesium transition chlorite,with ferrum being a little higher.It occurs as grain-coatings and pore linings and is mostly formed during the middle stage of diagenesis,closely related to ferrum-rich depositional environment.The chlorite content in the study area is positively related to porosity and permeability.The distribution and occurrence of chlorite plays an important role in affecting the porosity and permeability of reservoirs.Pore-lining and grain-coating chlorite and its overgrowth during diagenesis enhance the mechanical strength of rock and its ability of resistance to compaction.The chlorite also isolates detrital quartz surfaces from contact with pore water,thus preventing nucleation of authigenic quartz and consequently preserving pores in sandstone.
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2010年第6期674-679,共6页
Petroleum Exploration and Development
基金
国家重点基础研究发展规划(973)项目(2007CB209503)
国家重大专项项目(2008ZX05007-002)
关键词
川中地区
上三叠统
绿泥石
储集层物性
石英加大
central Sichuan Basin
Upper Triassic
chlorite
reservoir physical property
quartz overgrowth