Mathematics – Logic
Scientific paper
Mar 1993
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1993lpi....24.1017m&link_type=abstract
In Lunar and Planetary Inst., Twenty-Fourth Lunar and Planetary Science Conference. Part 2: G-M p 1017-1018 (SEE N94-16173 03-91
Mathematics
Logic
1
Carbonaceous Chondrites, Deuterium, Hydrogen Isotopes, Metamorphism (Geology), Meteoritic Composition, Petrography, Temperature Effects, Carbon, Distillation, Nitrogen, Thermoluminescence, Weathering
Scientific paper
Meteorites of the Ornans type 3 carbonaceous chondrites exhibit a range in degree of equilibration, attributed to differing amounts of thermal metamorphism. These differences have been used to split the CO3 chondrites into petrologic sub-types from 3.0, least equilibrated, to 3.7, being most equilibrated. This is similar to the system of assigning the type 3 ordinary chondrites into petrologic sub-types 3.0 to 3.9 based upon thermoluminescence (TL) and other properties; however, the actual range of thermal metamorphism experienced by CO3 chondrites is much less than that of the type 3 ordinary chondrites. The least equilibrated ordinary chondrites show evidence of aqueous alteration and have high D/H ratios possibly due to a deuterium-rich organic carrier. The aim of this study was to determine whether the CO3 chondrites, which have experienced similar secondary conditions to the type 3 ordinary chondrites, also contain a similar deuterium-rich carrier. To date a total of 5 CO3 meteorites, out of a set of 11 for which carbon and nitrogen isotopic data are available, have been analyzed. Ornans has not been analyzed yet, because it does not appear to fit in with the metamorphic sequence exhibited by the other CO3 chondrites; it also has an extremely high delta-D value of +2150 percent, unusual for such a comparatively equilibrated meteorite (type 3.4). Initial results indicate that the more equilibrated CO3's tend to have lower delta-D values, analogous to the higher petrologic type ordinary chondrites. However this is complicated by the effects of terrestrial weathering and the small data-set.
Morse Andrew D.
Newton Jonathan
Pillinger Colin T.
No associations
LandOfFree
A hydrogen isotope study of CO3 type carbonaceous chondrites; comparison with type 3 ordinary chondrites 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 A hydrogen isotope study of CO3 type carbonaceous chondrites; comparison with type 3 ordinary chondrites, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A hydrogen isotope study of CO3 type carbonaceous chondrites; comparison with type 3 ordinary chondrites will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1449967