In-situ nanoSIMS measurements of isotopic hotspots in the CM2 meteorite Cold Bokkeveld

Previous studies have identified iso-topic hotspots in insoluble organic matter (IOM) from carbonaceous chondrites. The origins and formation mechanisms of these hotspots and the host IOM are a matter of ongoing debate. For example, it is not clear whether D and 15N enrichments in IOM formed within a common organic precursor in cold interstellar environments or due to irradiation of organic material in the early Solar System. It is also unclear what effect parent body processes would have had with regard to the alteration of meteoritic IOM. In order to address these issues, more recent studies have attempted to make in-situ measurements of isotopic anomalies in IOM. In this study we present in-situ NanoSIMS isotopic analyses of material within a sample of the CM2 meteorite Cold Bokkeveld, comparing the distribution of hotspots and bulk H, C and N isotopic composition in the rims and interiors of altered chondrules