Characteristics and Exploration Strategy of the Middle Permian Hydrothermal Dolomite in Southwestern Sichuan Basin
详细信息
- 责任者：Chen Xuan (Key Laboratory of Exploration Technologies for Oil and Gas Resources ; Ministry of Education ; Yangtze University ; Jingzhou 434023 ; China) ; Zhao Wenzhi
- 刊名：Acta Petrolei Sinica
- 出版年：2013
- 卷期：34(3)
- 关键词：碳酸盐岩储集层 ; carbonate reservoirs ; 四川盆地 ; Sichuan Basin
- 页码：p.460-466
- 图表：illus., 2 tables, 24 refs.
- 分类号：1003
- issnNo：ISSN0253-2697
- isbnNo：CN11-2128/TE
摘要
Hydrothermal dolomitation can form high-quality dolomite reservoirs.Through mineralogic observations,geochemical analyses and comprehensive interpretations of seismic profiles,the Middle Permian saccharoidal dolomite in Qixia and Maokou formations which are related with hydrothermal dolomitization have following characteristics:(1) higher occurrence frequency,greater thickness in a single layer(5～40m),host limestone dominated by bioclasitc limestone or bioclasitc micrite;(2) residual bioclasitc textures developed in mesocrystalline-macrocrystallinpore dolomites and bioclast-dissolved pores partly filled with authigenic quartz and saddle dolostone mostly with intergranular and corroded pores,which porosity averages between 6%and 10%;(3) an obviously higher homogenization temperature of dolomite matrix(125～178℃) than the stratum temperature during dolomitization,which is indicated by more negative oxygen isotopes(-10.1‰～-11.42‰),higher 87Sr/86Sr(0.709 194～0.710 174)and positive Eu anomaly;(4) well-developed basement faults adjacent to dolomite-producing wells and a "sunken" reflection in corresponding seismic profiles.Generally speaking,close to basement fault zones,hydrothermal fluid dolomitization is intensive and dolomite reservoirs are thick and in good lateral continuity,where structure traps are exploration target.On the contrary,far from basement fault zones,hydrothermal fluid dolomitization is weak and dolomite reservoirs are thin and in poor lateral continuity,where hydrocarbon exploration should focus on litho-structure traps.
© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号 地址：北京市海淀区学院路29号 邮编：100083 电话：办公室：(+86 10)66554848；文献借阅、咨询服务、科技查新：66554700 |