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Mckay, G. A.

Publications and source records attributed to Mckay, G. A..

23 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

Breccias from the lunar highlands - Preliminary petrographic report on Apollo 16 samples 60017 and 63335.

Lunar samples 60017,4 and 63335,14 are composed of microbreccias and devitrified glass. These components are predominantly anorthositic, with the exception of a cryptocrystalline clast found in the microbreccia portion of 63335,14 which contains 2.7% potassium oxide and 66.7% silicon dioxide. The samples have been subjected to extreme shock and thermal metamorphism. The parent materials of the microbreccias include both a coarse-grained anorthosite and a fine-grained subophitic anorthositic gabbro.

Kridelbaugh, S. J.↗
NASA NTRS1972

Microprobe studies of three Luna 16 basalt fragments.

Three small fragments of Luna 16 basalt (NASA sample designation G38) have been analyzed with an electron microprobe. The mineralogy is generally similar to that found in Apollo 11 and 12 igneous rocks: major amounts of clinopyroxene, plagioclase, ilmenite and olivine; accessory spinel, troilite, Fe metal and residual phases. Unlike some Apollo 12 basalts, there is continuous zoning with no composition gap in the G38 spinels. Plagioclase analyses follow the same nonstoichiometric trends previously found in Apollo 11 and 12. The samples indicate a magmatic history (rapid crystallization from reduced melts) similar to that inferred from studies of Apollo 11 and 12 basalts.

Grieve, R. A. F.↗