Origin of the Station 7 boulder - A note

Abstract

The origin of the matrix types from the Apollo 17 Station 7 boulder is considered along with the origin of boulder material from Station 2, Boulder 1, and 73215. It is pointed out that the formation of the matrix rocks in this boulder and in the other Apollo 17 boulders in a single impact event is consistent with the isotopic evidence, ages, major-element chemistry, large ion lithophile (LIL) trace-element abundances, and textures. It had been suggested by Winzer et al. (1974), based on calculations from crystal-liquid partition coefficients for LIL trace elements, that target rocks corresponding in trace-element composition to the matrix types could have been produced by partial fusion of rocks similar to 77215. Using the same type of calculation, liquids quite similar in trace-element composition to the Station 7 boulder matrix types can be produced.