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Images of an area of QUE 99177 (CR2) matrix: (a) a secondary electron scanning electron micrograph, (b) a N isotope ratio map, (c) a C isotope ratio map, and (d) a H isotope ratio map. The isotopic maps were all measured by NanoSIMS. A relatively large 15N- and D-rich “vein” of organic matter is visible. Arrow in (c) indicates a highly 13C-enriched presolar SiC grain with no obvious spatial relationship to the organic matter.
