Dissipation at tidal and seismic frequencies in a melt-free Moon

F. Nimmo, U. H. Faul, Edward Garnero

Research output: Contribution to journalArticle

30 Citations (Scopus)

Abstract

We calculate viscoelastic dissipation in the Moon using a rheological (extended Burgers) model based on laboratory deformation of melt-free polycrystalline olivine. Lunar temperature structures are calculated assuming steady state conduction with variable internal heat production and core heat flux. Successful models can reproduce the dissipation factor (Q) measured at both tidal and seismic frequencies, and the tidal Love numbers h 2 and k 2, without requiring any mantle melting. However, the frequency-dependence of our model Q at tidal periods has the opposite sign to that observed. Using the apparently unrelaxed nature of the core-mantle boundary (CMB), the best fit models require mantle grain sizes of ̃1 cm and CMB temperatures of ̃1700 K. If melt or volatiles are present, the lunar temperature structure must be colder than our melt-free models. We estimate a present-day mantle heat production rate of 9-10 nWm -3, suggesting that roughly half of the Moon's radiogenic elements are in the crust.

Original languageEnglish (US)
Article numberE09005
JournalJournal of Geophysical Research E: Planets
Volume117
Issue number9
DOIs
StatePublished - 2012

Fingerprint

Moon
moon
dissipation
melt
lunar temperature
core-mantle boundary
Earth mantle
heat production
mantle
Q factor
heat
frequency dependence
temperature
olivine
Temperature
heat flux
Heat flux
crusts
Melting
grain size

ASJC Scopus subject areas

  • Geochemistry and Petrology
  • Geophysics
  • Earth and Planetary Sciences (miscellaneous)
  • Space and Planetary Science

Cite this

Dissipation at tidal and seismic frequencies in a melt-free Moon. / Nimmo, F.; Faul, U. H.; Garnero, Edward.

In: Journal of Geophysical Research E: Planets, Vol. 117, No. 9, E09005, 2012.

Research output: Contribution to journalArticle

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