Bulk composition and early differentiation of Mars

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

28

Planetary Sciences: Solid Surface Planets: Interiors (8147), Planetary Sciences: Solid Surface Planets: Volcanism (6063, 8148, 8450), Planetary Sciences: Solid Surface Planets: Remote Sensing, Planetary Sciences: Solid Surface Planets: Origin And Evolution

Scientific paper

We report the concentrations of K, Th, and Fe on the Martian surface, as determined by the gamma ray spectrometer onboard the 2001 Mars Odyssey spacecraft. K and Th are not uniformly distributed on Mars. K ranges from 2000 to 6000 ppm; Th ranges from 0.2 to 1 ppm. The K/Th ratio varies from 3000 to 9000, but over 95% of the surface has K/Th between 4000 and 7000. Concentrations of K and Th are generally higher than those in basaltic Martian meteorites (K = 200-2600 ppm; Th = 0.1-0.7 ppm), indicating that Martian meteorites are not representative of the bulk crust. The average K/Th in the crust is 5300, consistent with the Wänke-Dreibus model composition for bulk silicate Mars. Fe concentrations support the idea that bulk Mars is enriched in FeO compared to Earth. The differences in K/Th and FeO between Earth and Mars are consistent with the planets accreting from narrow feeding zones. The concentration of Th on Mars does not vary as much as it does on the Moon (where it ranges from 0.1 to 12 ppm), suggesting that the primary differentiation of Mars differed from that of the Moon. If the average Th concentration (0.6 ppm) of the surface is equal to the average of the entire crust, the crust cannot be thicker than about 118 km. If the crust is about 57 km thick, as suggested by geophysical studies, then about half the Th is concentrated in the crust.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Bulk composition and early differentiation of Mars 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 Bulk composition and early differentiation of Mars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Bulk composition and early differentiation of Mars will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1547424

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.