Thermal history of Mars and the sulfur content of its core

Conference · Thu Aug 30 04:00:00 EDT 1990 · Journal of Geophysical Research; (United States)

OSTI ID:5314067

Schubert, G ^[1]; Spohn, T ^[2]

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1. Univ. of California, Los Angeles (USA)
2. Westfalische Wilhelms-Universitaet Muenster (West Germany)

A model is presented for the thermal evolution of the Martian mantle and core and for the evolution of the Martian magnetic field. In the model, Mars is initially hot and completely differentiated into a core and mantle, consistent with evidence from SNC meteorites of early core formation in Mars. The subsequent evolution of Mars consists of a simple cooling, with interior temperature, surface heat flux, and core heat flux declining monotonically with time. Lithosphere thickness and mantle viscosity increase steadily through time. Heat transport across the mantle is accomplished by subsolidus convection which is parameterized by a Rayleigh number-Nusselt number relation. The core contains a light alloying constituent, assumed to be sulfur. Initial sulfur concentration x{sub s} is a principal parameter controlling core and magnetic field evolution. Model parameters such as core radius are functions of x{sub s} and are chosen consistent with the overall density and moment of inertia of Mars. The Martian mean moment of inertial I is allowed to vary between 0.365 M{sub p}r{sup 2}{sub p} and 0.345 M{sub p}r{sup 2}{sub p} (M{sub p} is the mass of Mars and r{sub p} is the radius of Mars), in accordance with recent inferences of the planet's moment of inertia from measurements of its gravitational oblateness.

• OSTI ID: 5314067
• Report Number(s): CONF-9001119--
• Conference Information: Journal Name: Journal of Geophysical Research; (United States) Journal Volume: 95:B9
• Country of Publication: United States
• Language: English

Related Subjects

640107* -- Astrophysics & Cosmology-- Planetary Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CHEMICAL COMPOSITION
CONVECTION
COOLING
DENSITY
DIMENSIONS
ENERGY TRANSFER
GEOLOGY
HEAT TRANSFER
MAGNETIC FIELDS
MARS PLANET
MASS TRANSFER
MATHEMATICAL MODELS
MORPHOLOGY
PHYSICAL PROPERTIES
PLANETARY EVOLUTION
PLANETS
SOLAR SYSTEM EVOLUTION
THICKNESS
VISCOSITY