On the resolution of density within the Earth

被引:150
作者
Masters, G
Gubbins, D
机构
[1] Univ Calif San Diego, SIO, IGPP, La Jolla, CA 92093 USA
[2] Univ Leeds, Sch Earth Sci, Leeds LS2 9JT, W Yorkshire, England
基金
英国自然环境研究理事会;
关键词
free oscillation; biassing effects; inner-core boundary(ICB);
D O I
10.1016/j.pepi.2003.07.008
中图分类号
P3 [地球物理学]; P59 [地球化学];
学科分类号
0708 ; 070902 ;
摘要
Roughly 30 years have passed since the last publication of a linear resolution calculation of density inside the Earth. Since that time, the data set of free oscillation degnerate frequencies has been completely re-estimated taking into account the biassing effects of splitting and coupling due to 3D structure. This paper presents a new resolution analysis based on the new data and focuses on two particular issues: (1) the density jump at the inner-core boundary which is important in discussions of the maintenance of the geodynamo; and (2) a possible density excess in the lowermost mantle which might be indicative of a "hot abyssal layer". We find that the density jump at the inner-core boundary is 0.82 +/- 0.18 Mg m(-3) which is significantly larger than previously thought. We also find little support for an excess density in the lowermost mantle though an increase of 0.4% is possible. (C) 2003 Elsevier B.V. All rights reserved.
引用
收藏
页码:159 / 167
页数:9
相关论文
共 23 条
[1]   Structure and dynamics of liquid iron under Earth's core conditions [J].
Alfè, D ;
Kresse, G ;
Gillan, MJ .
PHYSICAL REVIEW B, 2000, 61 (01) :132-142
[2]   UNIQUENESS IN INVERSION OF INACCURATE GROSS EARTH DATA [J].
BACKUS, G ;
GILBERT, F .
PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY OF LONDON SERIES A-MATHEMATICAL AND PHYSICAL SCIENCES, 1970, 266 (1173) :123-&
[3]   UPPER BOUND TO DENSITY JUMP AT BOUNDARY OF EARTHS INNER CORE [J].
BOLT, BA ;
QAMAR, A .
NATURE, 1970, 228 (5267) :148-&
[4]   On the thermal evolution of the Earth's core [J].
Buffett, BA ;
Huppert, HE ;
Lister, JR ;
Woods, AW .
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH, 1996, 101 (B4) :7989-8006
[5]  
Dahlen F. A., 1998, Theoretical global seismology
[6]   PARAMETRICALLY SIMPLE EARTH MODELS CONSISTENT WITH GEOPHYSICAL DATA [J].
DZIEWONSKI, AM ;
HALES, AL ;
LAPWOOD, ER .
PHYSICS OF THE EARTH AND PLANETARY INTERIORS, 1975, 10 (01) :12-48
[7]   PRELIMINARY REFERENCE EARTH MODEL [J].
DZIEWONSKI, AM ;
ANDERSON, DL .
PHYSICS OF THE EARTH AND PLANETARY INTERIORS, 1981, 25 (04) :297-356
[8]   INFORMATIVE SOLUTION TO A SEISMOLOGICAL INVERSE PROBLEM - (EARTHS INTERIOR STRUCTURE MASS MOMENT OF INERTIA) [J].
GILBERT, F ;
DZIEWONSKI, A ;
BRUNE, J .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1973, 70 (05) :1410-1413
[9]  
GILBERT F, 1971, GEOPHYS J ROY ASTR S, V23, P125, DOI 10.1111/j.1365-246X.1971.tb01807.x
[10]   APPLICATION OF NORMAL MODE THEORY TO RETRIEVAL OF STRUCTURAL PARAMETERS AND SOURCE MECHANISMS FROM SEISMIC SPECTRA [J].
GILBERT, F ;
DZIEWONSKI, AM .
PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES, 1975, 278 (1280) :187-269