Chemical compositions of impact melt breccias and target rocks from the Tenoumer impact crater, Mauritania

Details Chemical compositions of impact melt breccias and target rocks from the Tenoumer impact crater, Mauritania Chemical compositions of impact melt breccias and target rocks from the Tenoumer impact crater, Mauritania

Nov 2005

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2005m%26ps...40.1653p&link_type=abstract

Meteoritics, vol. 40, Issue 11, p.1653-1672

Computer Science

6

Scientific paper

The impact melt breccias from the Tenoumer crater (consisting of a fine-grained intergrowth of plagioclase laths, pyroxene crystals, oxides, and glass) display a wide range of porosity and contain a large amount of target rock clasts.Analyses of major elements in impact melt rocks show lower contents of SiO2, Al2O3, and Na2O, and higher contents of MgO, Fe2O3, and CaO, than the felsic rocks (i.e., granites and gneisses) of the basement. In comparison with the bulk analyses of the impact melt, the glass is strongly enriched in Si-Al, whereas it is depleted both in Mg and Fe; moreover, the impact melt rocks are variably enriched or depleted in some REE with respect to the felsic and mafic bedrock types. Gold is slightly enriched in the impact melt, and Co, Cr, and Ni abundances are possibly due to a contribution from mafic bedrock.Evidences of silicate-carbonate liquid immiscibility, mainly as spherules and globules of calcite within the silicate glass, have been highlighted.HMX mixing calculation confirm that the impact melt rocks are derived from a mixing of at least six different target lithologies outcropping in the area of the crater. A large contribution is derived from granitoids (50%) and mica schist (17-19%), although amphibolites (˜15%), cherty limestones (˜10%), and ultrabasites (˜6%) components are also present.

The very low abundances of PGE in the melt rock seem to come mainly from some ultrabasic target rocks; therefore, the contamination from the meteoritic projectile appears to have been negligible.

Affiliated with

Also associated with

No associations

Rating

Chemical compositions of impact melt breccias and target rocks from the Tenoumer impact crater, Mauritania 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 Chemical compositions of impact melt breccias and target rocks from the Tenoumer impact crater, Mauritania, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Chemical compositions of impact melt breccias and target rocks from the Tenoumer impact crater, Mauritania will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1634996