Theoretical and observed Q of the Chandler wobble —Love number approach

Abstract

This paper treats two principal problems on the Chandler wobble Q(Qw); (1) the most probable estimate for Qw (present estimates range from 30 to 600), and (2) the relation between the mantle Q(Qm) and Qw (present estimates vary over an order of magnitude). We must resolve both problems to discuss the frequency dependence of Qm and mantle rheology on firm ground. We modify Maximum Entropy Spectral Analysis to be suitable for estimating the Q value and show Qw exists in the range 50≲ Qw≲ 100. We compute the complex Love number k for the anelastic earth to reveal Qw/Qm≃ 1.5. If Qm depends on the frequency f such that Qm(f) ∝ fα and the mantle is the principal sink of the wobble energy, then 0.14 < α < 0.2.If the mantle absorbs only a minor fraction of the wobble energy, α should be less than the above values. Copyright © 1982, Wiley Blackwell. All rights reserved