Isotopic variations of Carbon and Nitrogen in graphite, crystallized under semi-equilibrated conditions in IAB iron meteorites

Abstract

we detail the formation of Iron meteorites, about how they have a unique cosmochemical and isotopic signature with respect to other meteoritic species. We quarry the models developed by different authors to explain the formation of iron meteorites, when did they form, how did they differentiate. Our special point of focus will be IAB iron meteorites as they are a unique class of iron meteorites, with unique petrology. Since IAB irons are known to have been formed by impact related processes and carry phases which might have been at some point in time, formed out of equilibrium. These phases might hold the clue to the paradox around the presence and loss of volatiles from the terrestrial planetary region. We carry out In-situ nano-SIMS analysis on graphite grains embedded within a metal matrix. these cores or metal pools have been formed through instantaneous melting or in many cases incomplete scavenging of metal melt diapirs through silicate matrix. with the high mass and spatial resolution of the ion probe we can effectively look for that very evidence. In the process we explore many other phases, that populate the metallic domains, like schreibersite and troilite which are iron-phosphorous and iron-sulphur alloys respectively. Work is underway to develop a diffusion based model which can, effectively model such scenarios in real time, and on comparison we can easily seed out the outliers, if there exist any. In this report we only report the trend in the data and general petrological observation. Hopefully the model data will be incorporated as soon as possible.