大陆边缘热状态研究进展  

Thermal regime in the continental margins: An overview

作　　者：雷晓[1,2] 刘绍文[1,2] 蒋学鸿[1,2] 曹萦[1,2] 王华玉[1,2] 

机构地区：[1]南京大学海岸与海岛开发教育部重点实验室,南京210046 [2]南京大学地理与海洋科学学院,南京210046

出　　处：《地球物理学进展》2013年第2期998-1012,共15页Progress in Geophysics

基　　金：国家自然科学基金(41176037);973课题(2007CB411704);南京大学大学生创新训练项目(XZ1110284065)资助

摘　　要：热流与岩石圈热状态是大陆边缘构造研究的重要课题,其研究不仅能为探讨发生在大陆边缘的物理、化学和生物过程提供地热约束,而且还能为深水油气资源评价和勘探提供依据.近年来,随着对海底过程研究的深入和对能源资源问题的关注,大陆边缘热状态研究取得了新认识,特别是,主动大陆边缘弧后地区高热流的认识及成因机制以及被动大陆边缘洋陆过渡带可能存在的高热流异常等这些重要发现,进一步丰富和完善了大陆边缘热状态的认识.本文总结了近年来大陆边缘热流研究进展,重点讨论了主动大陆边缘岛弧-弧后地区热状态和部分被动大陆边缘发现的高热流异常,前者一般被认为是与弧后地区岩石圈之下的浅地幔对流有关;而后者既包括来自浅层地壳生热贡献,也有深部地幔热流所致,一些学者将此归因于小尺度地幔对流或岩石圈厚度差异引发的边界效应,仍存争议.我们还分析了探针热流、钻孔热流和BSR热流等不同类型数据的优缺点,指出钻孔热流和BSR热流成为继传统探针热流之后研究大陆边缘热流的有效手段.在海底热流和近海底过程之间相互响应的基础上,强调热流探测对近海底过程研究的贡献.还对比了国内外热状态的研究,探讨了国内研究与国际的差距.最后,就未来大陆边缘热状态研究提出了几点建议.Heat flow and thermal regime of lithosphere are key aspects in studying the continental margin tectonics, considering they not only provide geothermal constraints for analyzing physical, chemical and biological processes taking place here, but also are the basis for assessing and exploring deep-water oil and gas resources. Recently, as the research of seafloor processes and the energy crisis are attracting people＇s more attention, some new advancements have been achieved on thermal regime of the continental margins, among which the high heat flow nature of backarcs in convergent margins and the high thermal anomalies existing in ocean-continent transitions （OCT） of divergent margins largely enriched and perfected our knowledge about it. The former is ascribed to the sublithospheric shallow mantle convection that occurred beneath backarcs. While the high thermal anomalies in OCT can result from both radiogenic heat generation of shallow crust and conductive heat flow from deeper lithosphere and is thought to be related to small-scale mantle convection or edge effect driven by a step change in lithospheric thickness. Both of these advancements were discussed in this paper, along with advantages and disadvantages of three generally applied heat flow detection methods as probe measurement, borehole temperature based and BSR derived heat flow, respectively. Also, we analyzed the interaction between near-seafloor processes and marine heat flow and emphasized on marine heat flow measurements in investigating the impact of near-seafloor processes. Furthermore, we compared the research of China with abroad. At last, several further suggestions were proposed about studying the regime of continental margins.

关 键 词：热流 热状态 小尺度地幔对流 大陆边缘 

分 类 号：P312[天文地球—固体地球物理学] P541[天文地球—地球物理学]