Skip to main content
Fig. 3 | Progress in Earth and Planetary Science

Fig. 3

From: Formation of ferroan dacite by lunar silicic volcanism recorded in a meteorite from the Moon

Fig. 3

Images of silicic clast and Raman maps showing silica polymorphs. Detailed explanations of each figure are as follows: a photomicrograph in plane polarized light; b back-scattered electrons (BSE); c RGB elemental map with R = Al, G = Ca, B = Fe, d RGB image with R = K, G = Si, B = P. Silica occurs as: (1) massive to elongate grains; (2) narrow domains enveloping thin plagioclase feldspar laths; and (3) elongate crystals intercalated with K-Ba-feldspar. Areas where Raman peaks were mapped are color-coded in panel b, with maps e, f enclosed in the yellow box, map g in the blue box, and map h in the purple box. The Raman peak intensity maps show the following peaks: e peak intensity at 351 cm−1 (tridymite); f peak intensity at 411 cm−1 (cristobalite); g peak intensity at 411 cm−1 (cristobalite); h peak intensity at 464 cm−1 (quartz). Warm colors (red) indicate high peak intensities and dark (blue) colors denote low intensities. Mineral abbreviations: Apa apatite, Fa fayalite, Ilm ilmenite, Kfs K-feldspar, Plg plagioclase, Px pyroxene, Si silica

Back to article page