CAIs and AOAs are both Refractory Inclusions скачать в хорошем качестве

CAIs and AOAs are both Refractory Inclusions

There is sometimes a confusion with respect to what are refractory inclusions (RI) Ca,Al-rich inclusions (CAIs) are certainly a type of RI, with an abundance of about 0-3 vol%. However, there is another abundant type of RI, which are amoeboid olivine aggregates (AOAs). The AOAs also have a condensation signature, and despite being primarily composed of olivine, likely also formed similar to CAIs and with a signature of more refractory elements and minerals. The abundance of AOAs can be significantly higher than CAIs, with up to more than 5 vol%. Hence, RI is a summative term, comprising CAIs, AOAs, and other, minor components, which is why the RI content of a chondrite can be up to more than 10 vol%.