收稿日期: 1999-05-28
修回日期: 1999-07-08
网络出版日期: 2000-04-01
基金资助
国家自然科学基金重点项目“中国及邻区地球内部各圈层三维结构及地球动力学”(编号:49734150)及国土资源部“九五”基础研究基金
项目联合资助。
STRUCTURE OF LOWER MANTLE AND CORE-MANTLE BOUNDARY REGION AND ITS GEODYNAMICS
Received date: 1999-05-28
Revised date: 1999-07-08
Online published: 2000-04-01
朱介寿 . 下地幔及核幔边界结构及地球动力学[J]. 地球科学进展, 2000 , 15(2) : 139 -142 . DOI: 10.11867/j.issn.1001-8166.2000.02.0139
The new generation of high-resolution seismic tomographic images of lower mantle and core-mantle boundary region have provided amazing insights for global tectonics and the dynamic processes of the Earth. The ancient oceanic lithospheric slabs sank into the bottom of the lower mantle, and the material of remnants slabs accumulated at the core-mantle boundary. The model of convective flow of the whole mantle was supported by the new seismic images. The D" discontinuity above the core-mantle boundary has a fine and complicated structure and interpreted as a chemical or phase transition zone, and add the possibility that the cold thermal anomaly associated ancient slabs leads to the velocity anomaly.One of the most exciting discovery is the ultralow velocity zone (ULVZ) which close the core-mantle boundary in lower mantle side, it may be the partial molten layer and the sources of the upwelling plume which cause the hot spots at the Earth' s surface.
Key words： Seismic tomography; Lower mantle; Core-mantle boundary; Geodynamics.
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