Issues to be solved on high 3He/4He in the Earth's interior - critical review on proposed models

Abstract

In order to study the chemical state of the Earth's interior, noble gases, especially He give special constraint on it, since they keep chemical properties different from those of solid elements. Particullary, OIBs show higher 3He/4He than MORBs. To explain such observations, so far many modela have been proposed, but each of them contains some problems. I will examine such problems and discuss issues to be considered on the chemical state of the Earth's interior.