核－幔边界的动力学背景

英文篇名：DYNAMIC BACKGROUND IN CORE-MANTLE BOUNDARY
中文刊名：地球物理学报
英文刊名：Chinese Journal of Geophysics
作者：李光品 ; 傅容珊
英文作者：LI GUANG-PIN ; FU RONG-SHAN (Department of Earth and Space Sciences ; University of Science and Technology of China ; Hefei 230026)
中文关键词：全地幔 ; 核－幔边界 ; 动力学背景．
英文关键词：Whole-mantle ; Core-mantle boundary ; Dynamic background.
出版日期：1995-07-17
机构：中国科学技术大学地球和空间科学系
年：1995
期：04
出版单位：地球物理学报

摘要

根据传播矩阵方法，并把由联合反演得到的同时满足长波地形起伏、板块运动速度、重力位异常资料以及地震层析先验知识的全地幔三维异常密度作为载荷，以求取核－幔边界的动力学背景．计算结果显示：１．所求的核－幔边界起伏图像与Ｈａｇｅｒ等根据格林函数方法所求得的核－幔边界的起伏在全球范围内基本相符．２．核－幔边界处的环型场仅在数量上降为地表处的环型场的１／８左右，而极型场较地表处的极型场的流动图像有显著变化，数值也增为地表处极型场的３倍左右．
Based on method of propagation matrix, we load three-dimension anomalous density of the mantle and calculate dynamic background in CMB. The calculated results indicate: 1. the topography of CMB is basically coherent with the result calculated by means of Green's function by Hager et. al. 2. the polidal field in CMB has a great change compared with that in the earth's surface, the magnitude of the polidal field in CMB is about three times as much as that in the earth's surface. 3.ihe toroidal field is similar to that in the earth's surface, but the it's magnitude st one-third as much as that in the earth's surface.

引文

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