Open AccessThe influence of a density stratification and of an incompressibility modulus on the spectrum of core modes
Author(s) -
Briers R.,
Dehant V.,
Leroy O.
Publication year - 1996
Publication title -
geophysical journal international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0956-540X
DOI - 10.1111/j.1365-246x.1996.tb04039.x
Subject(s) - compressibility , outer core , inner core , eigenvalues and eigenvectors , boundary value problem , core (optical fiber) , vibration , mathematical analysis , oscillation (cell signaling) , homogeneity (statistics) , normal mode , stratification (seeds) , boundary (topology) , physics , mathematics , classical mechanics , mechanics , geophysics , quantum mechanics , optics , seed dormancy , statistics , germination , botany , dormancy , biology , genetics
The concept of a deformation of a simple, non‐rotating, spherically symmetric earth model with a fluid outer core, although it is a highly artificial physical situation, provides a useful computational algorithm that allows one lo determine analytically modes of vibration without any Love‐number theory. In particular, on these analytically determined modes, we impose regularity conditions at the centre and boundary conditions at the surface, as well as conditions of continuity at the inner‐core‐outer‐core boundary and at the core‐mantle boundary. They lead to an eigenvalue equation for the frequency of oscillation. The range of frequencies obtained in this way for different earth models gives an indication of the influence of compressibility and non‐homogeneity on the spectrum of eigenfrequencies.