Apollo 15 green glass - Compositional distribution and petrogenesis

Other

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

14

Apollo 15 Flight, Glass, Petrography, Regolith, Space Probes, Trace Elements, Breccia, Distribution (Property), Electron Probes, Lunar Mantle, Neutron Activation Analysis

Scientific paper

We have characterized a comprehensive suite of individual green-glass beads from Apollo 15 soil to determine interelement behavior and to constrain petrogenetic relationships. We analyzed 365 particles for trace elements by instrumental neutron activation analysis and analyzed 52 of them, selected to cover the compositional ranges observed for trace elements, for major elements by electron microprobe analysis. We confirm the observation of Delano (1979) that the beads comprise discrete compositional groups, although two of the groups he defined are further split on the basis of trace-element compositions. Each of the resulting seven groups has distinct average rare-earth abundances. The coherence between major- and trace-element data was masked in previous studies by imprecision, correlated error, and nonrepresentative sampling of the different groups. Most of the compositional characteristics of the green glasses can be explained by a model for batch equilibrium melting of a nearly homogeneous, ultramafic source region, when the complicating effects of high pressure and low oxygen fugacity are taken into account. The previously puzzling behavior of Ni and Co as apparently incompatible elements may arise from partial reduction of those elements to the zero oxidation state, resulting in low mineral/melt partition coefficients. The model also offers explanations for why the green glasses form boomerang-shaped trends on many two-element variation diagrams and why certain compositions (Groups A and D) are more abundant than glasses with other compositions.

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

Apollo 15 green glass - Compositional distribution and petrogenesis 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 Apollo 15 green glass - Compositional distribution and petrogenesis, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apollo 15 green glass - Compositional distribution and petrogenesis will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1552659

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