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Read Full Article (file size: 303987 bytes) Cited by
GEOPHYSICAL RESEARCH LETTERS,
VOL. 34,
L16203,
doi:10.1029/2007GL030544,
2007
Mantle convection and magma production on present-day Mars: Effects of temperature-dependent rheology
Qingsong Li
Lunar and Planetary Institute, Houston, Texas, USA
Walter S. Kiefer
Lunar and Planetary Institute, Houston, Texas, USA
Abstract
Using recent volcanism on Mars as an important constraint, we explore the nature of present-day mantle convection using numerical
simulations with temperature-dependent Arrhenius viscosity. Increasing the activation energy decreases both the magma production
rate and the convective heat flux, while increasing the thermal Rayleigh number increases these quantities. For values of
the activation energy inferred from lab studies of olivine, a thermal Rayleigh number (defined with a volume-averaged viscosity)
exceeding 2 · 106 best fits the observational constraints, including the recent volcanism rate and the range of melt fractions in the shergottites.
The heat flux out of the core is low enough to avoid a magnetic dynamo, an important improvement over prior work. These results
indicate that present-day mantle convection on Mars remains relatively vigorous.
Received 3
May
2007;
accepted 23
July
2007;
published 24
August
2007.
Keywords: mantle convection;
Mars;
magma.
Index Terms: 5418 Planetary Sciences: Solid Surface Planets: Heat flow; 5430 Planetary Sciences: Solid Surface Planets: Interiors (8147); 5480 Planetary Sciences: Solid Surface Planets: Volcanism (6063, 8148, 8450); 6225 Planetary Sciences: Solar System Objects: Mars; 8121 Tectonophysics: Dynamics: convection currents, and mantle plumes.
Read Full Article (file size: 303987 bytes) Cited by
Citation: Li, Q., and W. S. Kiefer
(2007),
Mantle convection and magma production on present-day Mars: Effects of temperature-dependent rheology,
Geophys. Res. Lett.,
34,
L16203,
doi:10.1029/2007GL030544.
Copyright 2007 by the American Geophysical Union.
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