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The bulk composition, mineralogy and internal structure of MarsA bulk composition for Mars is derived to a pressure-dependent mineralogy. The density distribution of the present model is compared with density distributions derived from the global gravity field. It is argued that the uppermost Martian mantle is likely to be dominated by olivine and orthopyroxene, as is the earth's upper mantle, although the Martian mantle has a lower MgO/(MgO + FeO) ratio (0.74 vs 0.89). The olivine-peridotite layer extends to a depth of 900 to 1100 km where the transition to silicate spinel begins. Calculations of the high-pressure liquidus and solidus temperatures indicate that for the case of a molten core the minimum temperature at the core-mantle boundary is about 2000 K, whereas for the case of a solid core the maximum temperature is about 1800 K. Summation of the masses in the various layers of Mars yields a value of 0.353 for the dimensionless moment of inertia, which is intermediate between the generally accepted value of 0.365 and the value of 0.345 predicated on a nonaxisymmetric distribution of mass about the Tharsis plateau.
Document ID
19930043861
Document Type
Conference Proceedings
Authors
Longhi, John (Lamont-Doherty Geological Observatory Palisades, NY, United States)
Knittle, Elise (California Univ. Santa Cruz, United States)
Holloway, John R. (Arizona State Univ. Tempe, United States)
Waenke, Heinrich (Max-Planck-Inst. fuer Chemie Mainz, Germany)
Date Acquired
August 16, 2013
Publication Date
January 1, 1992
Publication Information
Publication: In: Mars (A93-27852 09-91)
Subject Category
LUNAR AND PLANETARY EXPLORATION
Funding Number(s)
CONTRACT_GRANT: NAGW-182
CONTRACT_GRANT: NAG9-93
Distribution Limits
Public
Copyright
Other