期刊
PHYSICS OF THE EARTH AND PLANETARY INTERIORS
卷 192, 期 -, 页码 68-80出版社
ELSEVIER
DOI: 10.1016/j.pepi.2011.10.001
关键词
Chandler wobble; D '' layer; Viscosity; Tidal deformation; Maxwell body
资金
- Japanese Ministry of Education, Science and Culture [22540440]
- Grants-in-Aid for Scientific Research [22540440] Funding Source: KAKEN
Viscosity of the D '' layer of the Earth's mantle, the lowermost layer in the Earth's mantle, controls a number of geodynamic processes, but a robust estimate of its viscosity has been hampered by the lack of relevant observations. A commonly used analysis of geophysical signals in terms of heterogeneity in seismic wave velocities suffers from major uncertainties in the velocity-to-density conversion factor, and the glacial rebound observations have little sensitivity to the D '' layer viscosity. We show that the decay of Chandler wobble and semi-diurnal to 18.6 years tidal deformation combined with the constraints from the postglacial isostatic adjustment observations suggest that the effective viscosity in the bottom similar to 300 km layer is 10(19)-10(20) Pa s, and also the effective viscosity of the bottom part of the D '' layer (similar to 100 km thickness) is less than 10(18) Pa s. Such a viscosity structure of the D '' layer would be a natural consequence of a steep temperature gradient in the D '' layer, and will facilitate small scale convection and melt segregation in the D '' layer. (C) 2011 Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据