The Ingredients of the “subsolar” Noble Gas Component

Introduction: On the basis of several experiments on separates of the EH5 chondrite St. Mark’s, we will argue that the “subsolar” noble gas component is a mixture of solar-like, Qand terrestrial noble gases. The subsolar noble gas component has been found, in particular, in E chondrites [1,2] but also in other meteorite classes (e.g. aubrites, CO or CH chondrites [3-5]). This component is elementally and isotopically intermediate between the common meteoritic “Q-gas” [6] and solar composition. Experiments have never established a well-defined subsolar endmember. South Oman (EH4/5) is used as reference for subsolar element ratios [1,7]. The isotopic ratios follow the elemental trend, being intermediate between Q and solar, or even roughly solar [7].