Argon Degassing Models of the Earth

• DOI: 10.1038/physci245020a0
• Publication Date: 2013-07-09T10:36:01Z
• Authors: DAVID W. SCHWARTZMAN
• Keywords: Early Earth

THERE have been many attempts to model Ar degassing of the Earth. In one category1–6 models are implicitly coherent in regard to K and Ar; 40Ar which has been accumulating with parent K in the mantle is degassed when K enters the crust. I have discussed in detail the implications of such a model to the origin of the sialic crust elsewhere (refs 7 and 8 and D. W. S., to be published). The other major approach has been to treat Ar degassing according to a first order rate process; degassing rate is proportional to the content of 40Ar in the Earth at any time9–12.