Shock-induced metallic iron nanoparticles in olivine-rich Martian meteorites

Details Shock-induced metallic iron nanoparticles in olivine-rich Martian meteorites Shock-induced metallic iron nanoparticles in olivine-rich Martian meteorites

Oct 2007

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2007e%26psl.262...37v&link_type=abstract

Earth and Planetary Science Letters, Volume 262, Issue 1-2, p. 37-49.

Mathematics

Logic

19

Scientific paper

Magnetic anomalies observed by the Mars Global Surveyor mission are attributed to crustal remanence. SNC (Shergotty Nakhla Chassigny) meteorites are likely samples of the Martian crust and are amenable to mineralogical and magnetic measurements essential to the understanding of the origin of magnetic anomalies. The recently discovered chassignite NWA 2737 and lherzolitic shergottite NWA 1950 display unusual magnetic characteristics that argue for a different magnetic carrier than the oxides and sulfides previously invoked in SNC meteorites. NWA 2737, the second member of the chassignite group, is a dunite with unusually dark-brown olivines and large magnetic susceptibility while Chassigny contains green olivines and is nearly a pure paramagnet. Dark olivines are also found in NWA 1950, a lherzolitic shergottite, which has singular magnetic properties when compared with other shergottites. The dark olivine color is due to the presence of Fe and FeNi metal nanoparticles, identified both by TEM and by magnetic measurements. Their size distribution encompasses the superparamagnetic to single domain transition at 30 K (10 nm range) and explains the magnetic properties of the bulk rocks. The formation of these nanoparticles is attributed to heating during the shock events that affected NWA 2737 and NWA 1950. The production of metal particles by shock-induced reduction of olivine has been invoked on surfaces deprived of atmosphere but never observed on Earth or Mars. Therefore, metal formed by shock in the heavily cratered Noachian crust is a possible carrier for crustal magnetic remanence. Widespread surface formation of metal nanoparticles could provide the precursor for the oxidized particles (goethite, hematite) observed in the Martian soils.

Affiliated with

Also associated with

No associations

Rating

Shock-induced metallic iron nanoparticles in olivine-rich Martian meteorites 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 Shock-induced metallic iron nanoparticles in olivine-rich Martian meteorites, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Shock-induced metallic iron nanoparticles in olivine-rich Martian meteorites will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1068038