Evolution of KREEP - Further petrologic evidenceIt is hypothesized that KREEP samples from the Apollo 15 site are igneous. To support the hypothesis, comparisons are made with other crystalline KREEP samples, especially 14310. It is noted that the low siderophile element content and lack of high pressure phenocrysts in the Apollo 15 KREEP may be indications of a slower rise of KREEP melt to the surface, when contrasted with sample 14310. Gravitational separation of Fe-Ni metal is proposed as a mechanism to account for the depletion of siderophile elements relative to the Si-rich component. It is further suggested that KREEP may be the parent of Apollo 12 and 15 basalts, as well as of granitic rocks, due to the liquid immiscibility occurring during the KREEP melt crystallization, and the subsequent independent evolution of the components.
Document ID
19780057782
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Crawford, M. L. (Bryn Mawr College Bryn Mawr, Pa., United States)
Hollister, L. S. (Princeton University Princeton, N.J., United States)