EarthRef.org Reference Database (ERR)
Development and Maintenance by the EarthRef.org Database Team

Detailed Reference Information
Sohl & Spohn 1997
Sohl, F. and Spohn, T. (1997). The interior structure of Mars: Implications from SNC meteorites. Journal of Geophysical Research 102: doi: 10.1029/96JE03419. issn: 0148-0227.

Two end-member models of Mars' present interior structure are presented: the first model is optimized to satisfy the geochemical data derived from the SNC meteorites in terms of the bulk chondritic ratio Fe/Si=1.71, while the second model is optimized to satisfy the most probable maximum value C=0.366¿Mprp2 of the polar moment of inertia factor. Hydrostatic equilibrium and stationary heat transfer are assumed, and the basic differential equations for the mechanical and thermal structure are solved numerically together with an isothermal Murnaghan-Birch type equation of state truncated in Eulerian strain at forth order. We obtain the radial distribution of mass, hydrostatic pressure, gravity, temperature, and heat flow density along with the corresponding density stratification, viscosity profiles, and the global seismic velocity structure of model Mars. The first model being consistent with the geochemical requirement produces C=0.357¿Mprp2, whereas the second model commensurate with the geophysical constraint gives Fe/Si=1.35. The calculated central pressure is about 40 GPa in both models, and the central temperature is in the 2000 to 2200 K range. The model calculations suggest a Fe-Ni-FeS core a little less than one half of the planetary radius in size surrounded by a silicate mantle subdivided into lower spinel and upper olivine layers and overlain by a 100- to 250-km thick basaltic crust and a surface heatflow density of 25 to 30 mW m-2. In both models the pressure in the mantle is not sufficient for the spinel to perovskite transition to occur. The present thermal lithosphere is estimated to be about 500 km thick and to be subdivided into a 300-km-thick outermost rheological lithosphere and an underlying thermal boundary layer of mantle convection. Given the core sulfur content of 14 wt% as derived from SNC meteorites, the Martian core is found to be entirely molten, implying the nonoperation of a self-sustained dynamo due to the absence of sufficiently vigorous convection.¿ 1997 American Geophysical Union

BACKGROUND DATA FILES

Abstract

Keywords
Planetology, Solar System Objects, Mars, Planetology, Solid Surface Planets, Interiors, Planetology, Solid Surface Planets, Composition, Planetology, Solar System Objects, Meteorites and tektites
Journal
Journal of Geophysical Research
http://www.agu.org/journals/jb/
Publisher
American Geophysical Union
2000 Florida Avenue N.W.
Washington, D.C. 20009-1277
USA
1-202-462-6900
1-202-328-0566
service@agu.org
Click to clear formClick to return to previous pageClick to submit