Fig. 9
From: Mineralogy and noble gas isotopes of micrometeorites collected from Antarctic snow
Transmission electron microscopy (TEM) images of moderately heated micrometeorites (MMs). a High-angle annular diffraction-scanning transmission electron microscope (HAADF-STEM) image of D10IB020, containing abundant olivine (Ol) and interstitial glass (Gl) with small amounts of kamacite (Km) and chromite (Chr). Bright-field images of b D10IB049, composed of <2-μm low-Ca pyroxene and c D10IB130, composed of a single olivine crystal. d HAADF-STEM image of an enlarged area indicated by the boxed area in (c). Wormy magnetite crystals (white) have developed at the original surface, which is the boundary between wormy magnetite-rich areas and upper right white area, which is W deposition protecting the surface during focused ion beam (FIB) processing. The magnetite was likely formed by atmospheric entry heating and oxidation. e Bright-field image of wormy magnetite crystals (Mt) embedded in glass (Gl)