Research on Cap Rock, Pressure Seal and Abnormal Pressure System
详细信息
- 责任者：Liu Weixin (Wuxi Research Institute of Petroleum Geology ; SINOPEC ; Wuxi 214151 ; China) ; Cheng Qiuquan
- 刊名：Petroleum Geology & Experiment
- 出版年：2011
- 卷期：33(1)
- 关键词：盖层 ; cap rocks ; 超压 ; overpressure ; 四川盆地 ; Sichuan Basin ; 辽河平原 ; Liaohe Plain
- 页码：p.74-80, 86
- 图表：10 illus., 10 refs.
- 分类号：1003
- issnNo：ISSN1001-6112
- isbnNo：CN32-1151/TE
摘要
Based on studies of the Mesozoic unconventional tight sandstone gas reservoirs in the western depression of the Sichuan Basin, it was found that sealing capability of caprocks depends on not only micropores, but also fractures and pore fluid pressures. Researches of the Tertiary oil and gas reservoirs in the western depression of the Liaohe Basin proved that undercompacted mudstones worked as effective overpressure sealing for hydrocarbon accumulations. Based on researches of abnormal pressure and overpressure sealing, it was concluded that the optimal targets of exploration were the compartments with huge volume, high pressure coefficient and low pressure gradient, as well as the traps immediately below main overpressure sealing surfaces of undercompacted zones. These concepts are summarized as abnormal pressure sealing controlling hydrocarbon accumulations.