The Villalbeto de la Peña Meteorite: Raman Spectroscopy and Cathodoluminescence of Feldspar

Abstract

This paper mainly focuses on the spatial distribution of plagioclase phases observed by Raman and spectra cathodoluminescence (CL) emission of in the Villalbeto de la Peña meteorite. Initially, we collected fragments countryside to determine the strewn field area and to perform spot chemical analyses by electron microprobe for the classification of the specimens (L6 Chondrite). Furthermore, the hyperspectral Raman mapping allow us identify amorphous Maskelynite feldspar in plagioclase micro-fissures since it is a molecular technique. The spectra CL emission bands observed at circa 290, 340, 390, 440, 510, 640 and 780 nm are characteristic in aluminosilicate lattices providing additional data on H+, OH- and H2O and Na+ self-diffusion along interfaces (290 nm), on strained Si—O bonds (340 and 650 nm), on [AlO4]° centers (380-390 nm and 420-440 nm), on O-—Si…M+ centers (510 nm) and on substitutional Fe3+ in aluminum positions (740—800 nm broad band). The CL and hyperspectral Raman techniques coupling demonstrates that the Villalbeto meteorite was shock-metamorphosed from the amorphous Maskelynite presence in Plagioclase fissures and from the strained Si—O bonds at room temperature.