Origin of 78235, a lunar norite cumulateA chemical and petrographic study is reported of the phases from the rock 78235 which was returned on the Apollo 17 mission. Petrographic analysis of the thin sections from the bounder confirm its cumulate origin. In order to develop further the crystallization history for 78235, its subsequent shock history, and its relationship to other lunar crustal rocks, orthopyroxene, plagioclase, glass, and whole-rock samples were prepared and analyzed for major, minor, and trace elements. It is speculated that an early fractional crystallization event producing a layer of orthopyroxene-plagioclase cumulate with varying amounts of trapped liquid took place within 20 km of the surface of the moon.
Document ID
19780062761
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Winzer, S. R. (Martin Marietta Laboratories Baltimore, Md., United States)
Nava, D. F. (Martin Marietta Labs. Baltimore, MD, United States)
Lum, R. K. L. (Martin Marietta Labs. Baltimore, MD, United States)
Schuhmann, S. (Martin Marietta Labs. Baltimore, MD, United States)
Schuhmann, P. (Martin Marietta Labs. Baltimore, MD, United States)
Philpotts, J. A. (NASA Goddard Space Flight Center Greenbelt, Md., United States)