Effects of compositional variation on absorption spectra of lunar pyroxenes.
Abstract
Polarized absorption spectra of lunar pyroxenes with a range of iron, calcium, magnesium, titanium and chromium contents were measured on polished, oriented single crystals; spectral data on pure synthetic FeSiO3 were also recorded. The bands at 1 and 2 microns were found to vary significantly in position with composition within the pyroxene quadrilateral; wavelengths increased with increasing calcium and iron. In the visible region, a weak band at 640 nm correlates in intensity with Cr2O3, but not with titanium as had been previously suggested. The 505-nm ferrous iron peak is a sharp doublet in most low-calcium pyroxenes but a singlet in augites. A peak at 475 nm and an intense absorption edge below 700 nm correlated with titanium content.
- Publication:
-
Lunar and Planetary Science Conference Proceedings
- Pub Date:
- 1978
- Bibcode:
- 1978LPSC....9.2919H
- Keywords:
-
- Absorption Spectra;
- Infrared Spectra;
- Lunar Rocks;
- Petrology;
- Pyroxenes;
- Chemical Composition;
- Selenology;
- Single Crystals;
- Spectral Bands;
- 10047;
- 12001;
- 12021;
- 12033;
- 12040;
- 12041;
- 12063;
- 14053;
- 14306;
- 70017;
- 73241;
- 73261;
- 74275;
- LUNA 24-182;
- CHROMIUM;
- LUNA 24;
- LUNA 22;
- LUNA 20;
- PYROXENES;
- ABSORPTION;
- SPECTRA;
- TITANIUM;
- OXIDATION;
- Lunar and Planetary Exploration; Moon;
- Moon:Local Properties