Spinel Troctolite and Anorthosite in Apollo 16 Samples

See allHide authors and affiliations

Science  05 Jan 1973:
Vol. 179, Issue 4068, pp. 74-76
DOI: 10.1126/science.179.4068.74


A spinel troctolite and an anorthosite from the Apollo 16 landing site represent contrasting types of "primitive" lunar cumulates. The two rock types probably formed from the same parent magma type, a high-alumina magnesian basalt, with the troctolite forming earlier by crystal settling, and the anorthosite later, possibly by flotation.