Other
Scientific paper
Jan 2002
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2002e%26psl.195....1m&link_type=abstract
Earth and Planetary Science Letters, Volume 195, Issue 1-2, p. 1-16.
Other
47
Scientific paper
The relationship between gravity and topography of various regions of Mars is used to estimate their effective elastic thicknesses Te using direct measurements of line of sight velocity, rather than spherical harmonic coefficients. Estimates of Te vary from 70 km for Tharsis, 29 km for Elysium, to 14.5 km for the southern hemisphere, and show that the thickness of the Martian lithosphere increases with age as the radioactive isotopes of K, Th, and U decay. A simple parameterised model of the convective thermal history is used to estimate the temperature structure of the lithosphere, and shows that the base of the elastic layer has a temperature of 300+/-50°C, or similar to the value for terrestrial continents. In both cases the rheology is probably affected by the presence of water. The short wavelength behaviour of the gravity field allows the density of the rocks that form the topography to be estimated, and gives values of about 3.0 Mg/m3 for Tharsis and Elysium. This value is substantially greater than that of 2.7 Mg/m3 obtained for Earth, and is in agreement with estimates from SNC (Shergottites-Nahklites-Chassigny) meteorites of 3.3 Mg/m3. The density of the topography of Valles Marineris is only 2.35 Mg/m3, and suggests that ice may be present below the surface. In the heavily bombarded southern hemisphere, isostatic compensation occurs at wavelengths as short as 700 km, which requires the effective compensation depth to be no more than 10 km. The gravity field with wavelengths greater than 1500 km may be supported dynamically, by a plume rising beneath the Tharsis region. The difference in temperature between the solidus and the present areotherm is less than 250°C, so melt generation can occur in rising plumes.
Barnett David N.
McKenzie Dan
Yuan Dah-Ning
No associations
LandOfFree
The relationship between Martian gravity and topography does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The relationship between Martian gravity and topography, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The relationship between Martian gravity and topography will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1089108