Quartz Cement in Middle Jurassic Reservoir Sandstones in North Sea A Review.PartⅡ:Duration and Silica Sources
- 出版年：2000
- 作者：Shao-nan Zhang；Knut BjΦrlykke
- 单位1：Chengdu University of Technofogy Chengdu
- 出生年：1957
- 职称：Professor
- 语种：中文
- 作者关键词：quartz cementation；reservoir sandstones；North Sea
- 起始页：119
- 总页数：8
- 刊名：沉积学报
- 是否内版：否
- 刊频：季刊
- 创刊时间：1983
- 主办单位：中国科学院兰州地质研究所；沉积学会
- 主编：叶连浚
- 卷：18
- 期：1
- 期刊索取号：P371.066243
摘要
The timing and duration of quartz cementation in sandstones have been mainly inferred from diagenetic tex-ture, relatiopship between pore filling minerals, fluid inclusions and isotopic data. Fluid inclusion temperatures fromNorth Sea reservoir sandstones indicate that most of the quartz cement forms at temperature exceeding 90℃ and is con-tinually proceeding after oil emplacement, based on the fluid inclusion temperatures in quartz overgrowth which is ap-proaching the bottom-hole temperatures. The duration of quartz cement after oil emplacement depends upon the satu-ration of porewater and the distribution of pore water film and the property of water-wet or oil- wet of the reactants.The leaching of K-feldspar by meteoric water requires pore water flow to move the released potassium and sodium andsilica out the solution, which suggests the mechanism does not appear to be a major source of silica for quartz cementa-tion. The quartz cementation coincidence with the compaction and pressure solution suggests the major source of silica.The alteration of feldspar by illitization of kaolinite may serve as another important source of silica at deep burial depth.External sources are not need to call on for illustrating the quartz cementation, because there is no evidences for largescale convection of pore water flow occurred in the burial history of reservoir sandstones of middle Jurassic in the NorthSea.