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Ebihara, Mitsuru

Publications and source records attributed to Ebihara, Mitsuru.

Trace elements in 59 mostly highland moon rocks

New chemical analyses for up to 26 trace elements, including seldom-determined highly siderophile elements Ir, Os, Re, Au, Pd, and Ge, for 59 lunar samples are reported. Most of these samples are polymict breccias from Apollo 16. Remarkably few have Group 7 (extremely low Au/Ir) meteoritic components. Several samples have uncommonly high Au/(Ir + Re) ratios, even higher than group 1L. Volatile-element enrichments are found in several fragments from rusty rock 66095. A matrix sample from fragmental breccia 60639 shows Cd and In enrichments, also observed previously in samples of anorthosite and mare basalt from the same breccia. Evidently, for these highly labile elements, chemical exchange has affected clasts that for most other elements are pristine.

Ebihara, Mitsuru↗

Ureilites - Trace element clues to their origin

The question of the origin of ureilites was reexamined using new data obtained by radiochemical NAA for Ag, Au, Bi, Br, Cd, Cs, Ge, In, Ir, Ni, Pd, Os, Rb, Re, Sb, Se, Te, Tl, U, and Zn in two vein separates from Haveroe and Kenna and a bulk sample of Kenna. Vein material was found to be enriched in all elements analyzed, except Zn, and to account for most of the carbon, noble gases, and, presumably, siderophiles in the meteorite. The results support the earlier interpretation of Higuchi et al. (1976) on the composition of ureilite parent body (similar to C3V or H3, but not C3O chondrites).

Janssens, Marie-Josee↗