摘要
通过对库车前陆盆地超高压封存箱构造环境的分析,解释了该区“封存箱”的本质是断裂构造封存.超高压系统处于韧、脆性互变构造带,其是超高压和天然气保存的构造环境和基本条件.非能干层及沿其发育的滑脱层和逆掩断层作为“压力封存箱”的顶板或底板,其在垂向上起到封隔压力的作用.区域非能干层具有毛细管和异常高压双重封闭机制,滑脱层和逆掩断层大大增强其所到之处非能干层的封闭能力.压性、压扭性逆冲断层和平移断层侧向封闭,将构造区分割成互不连通的压力封存箱,亦成为“压力封存箱”的侧板.
Overpressure compartment in Kuqa foreland basin was analyzed in tectonics and was interpreted as fault seals. It is found that the overpressure system is in the interbedded zone of the ductile and brittle layers. The zone forms the basic factors and tectonic environment for overpressure and natural gas to be preserved. The bottom and top boundaries of overpressure compartments are ductile layers, as well as slip faults and overthrust faults which grew in the ductile layer. The sealing mechanisms of ductile layers were capillary seals and abnormally high-pressure seals, while slip faults and overthrust faults intensified enormously the sealing ability of the ductile layer. High-angle thrust faults and shift faults, which were laterally sealed, were used as lateral boundaries of the compartment to divide a tectonic province into press compartments that were not connected to each other.
基金
国家重点基础研究发展规划项目(2001CB209133)
国家自然科学基金(40172072
40472074)资助
关键词
前陆盆地
库车
韧、脆性互变构造带
封存箱
foreland basin
Kuqa
interbedded zone of ductile and brittle layers
compartment
