Pristine nonmare rocks and the nature of the lunar crust.
Abstract
It is shown that the interdisciplinary study of the nonmare lunar rocks based on trace element, major element, and isotopic data plus petrographic evidence can succeed in amassing a large suite of demonstrably pristine rocks, and that the relative numbers of these rocks are not in accord with statistics amassed on soil fragments and glasses. The term 'pristine' is taken to mean rocks with primary compositions (albeit not necessarily textures) produced by lunar endogenous igneous processes. Melt rocks and crystalline matrix breccias produced by impact processes are excluded. A petrographic synonym for pristine would be 'unremelted, monomict'. It is found that anorthositic norites and noritic anorthosites were rare as primary nonmare rocks. Mechanical mixing appears to have been the dominant petrogenetic process on the highlands.
- Publication:
-
Lunar and Planetary Science Conference Proceedings
- Pub Date:
- 1977
- Bibcode:
- 1977LPSC....8.2215W
- Keywords:
-
- Abundance;
- Lunar Composition;
- Lunar Crust;
- Lunar Rocks;
- Petrology;
- Apollo 16 Flight;
- Chemical Elements;
- Highlands;
- Igneous Rocks;
- Lunar Maria;
- Meteoroids;
- Minerals;
- Mixing;
- Petrography;
- Spectrometers;
- Lunar and Planetary Exploration