从裂陷期到裂后期被动陆缘盆地构造-热事件  

Tectono-thermal Events of Passive Continental Margin Basins from Syn-to Post-rift Stages

作　　者：李刚 梅廉夫[1] 郑金云 

机构地区：[1]中国地质大学(武汉)构造与油气资源教育部重点实验室,湖北武汉430074 [2]中海石油深海开发有限公司,广东深圳518054

出　　处：《地球科学与环境学报》2017年第6期773-786,共14页Journal of Earth Sciences and Environment

基　　金：国家科技重大专项项目(2016ZX05026-003-001)

摘　　要：构造-热事件是盆地在发育过程中构造活动与盆地热演化发生相互作用的地质事件。含油气盆地构造-热事件研究对揭示盆地成盆过程及油气生烃、排烃、运移和聚集等具有重要意义。通过研究世界范围内典型被动陆缘盆地裂陷期—裂后期热演化及其热机制,分析对比南海南、北陆缘盆地构造-热模拟研究成果,总结了被动陆缘盆地裂陷期—裂后期热演化的普遍规律及其可能热机制。结果表明:被动陆缘盆地裂陷期热演化与裂陷过程具有良好的相关性,盆地热流随裂陷作用过程逐渐增大,在裂陷末期达到最大值,其动力学机制主要与岩石圈伸展作用有关;裂后期盆地热演化整体为热衰减过程,但受盆地所处构造位置及周围板块构造活动影响,裂后期热衰减变化幅度减缓甚至再次经历加热过程;珠江口盆地深水区现今高热流特征主要与岩石圈强烈减薄和晚中新世以来的东沙运动有关;被动陆缘盆地构造-热事件未来进一步研究应不断尝试建立新的构造-热模型,以构造为导向探究成盆深部动力过程,揭示构造-热机制。Tectono-thermal events are the interactive geological events,which occur between tectonic activities and thermal evolution in the development of the basin.The study on tectonothermal events of hydrocarbon-bearing basins is of great importance for revealing the dynamics of the basin formation,hydrocarbon generation,expulsion,migration and accumulation.The thermal evolution and mechanism of typical passive continental margin basins in the global from syn-to post-rift stages were discussed;the tectono-thermal modeling research findings in the southern and northern continental margin basins of South China Sea were analyzed contrastively;and the universal laws and possible thermal mechanism of tectono-thermal evolution of passive continental margin basins from syn-to post-rift stages were summarized.The results show that the syn-rift thermal evolution has a good correlation with rifting process of passive continental margin basins;the basin heat flow increases gradually with rifting process,and reaches the peak at the end of syn-rift stage;the thermal dynamic mechanism is primarily relative to thelithospheric thinning;the thermal evolution is a decay process through the whole post-rift stage,but the basin is affected by the surrounding plate tectonic activities and the location,the basin heat flow decreased slowly or increases once again;the characteristics of high heat flow in the deep water areas of Pearl River Mouth Basin are mainly relative to the intense lithospheric thinning and Dongsha movement since Late Miocene;the study on tectono-thermal events of passive continental margin basins in the future should constantly try to construct a new tectonothermal model,and use tectonics-oriented thoughts to study the deep dynamic process of basin evolution for revealing the tectono-thermal mechanism.

关 键 词：被动陆缘 裂陷期 裂后期 构造-热事件 热演化 热机制 珠江口盆地 

分 类 号：P544.4[天文地球—构造地质学]