Melt inclusions in olivine crystals from chondrules: New insights from nanoscale concentration profiles in the Semarkona chondrite

We performed the first NanoSIMS study on melt inclusions (MI) hosted in olivine from type-II chondrules in the Semarkona chondrite. At this nanometric scale, a one- to two-micrometre smooth contact has been discovered between the host crystal (olivine) and the melt inclusion. All profiles show smooth concentration gradients linking two plateaus (one for olivine and the other for the melt inclusion), and some of them also show bumps and valleys in several elements (Fe and Si for example). Different processes can be envisaged to explain those smooth profiles, more or less successfully.