| タイトル | Early history of the moon: Implications of U-Th-Pb and Rb-Sr systematics |
| 本文（外部サイト） | http://hdl.handle.net/2060/19750006617 |
| 著者（英） | Unruh, D. M.; Nunes, P. D.; Tatsumoto, M. |
| 著者所属（英） | Geological Survey |
| 発行日 | 1974-01-01 |
| 言語 | eng |
| 内容記述 | Anorthosite 60015 contains the lowest initial Sr-87/Sr-86 ratio (0.69884 + or - 0.00004) yet reported for a lunar sample. The initial ratio is equal to that of the achondrite Angra dos Reis and slightly higher than the lowest measured Sr-87/Sr-86 ratio for an inclusion in the C3 carbonaceous chondrite Allende. The Pb-Pb ages of both Angra dos Reis and Allende are 4.62 x 10 to the 9th power years (4.62 billion years). Thus, the initial Sr-87/Sr-86 ratio found in lunar anorthosite 60015 strongly supports the hypothesis that the age of the moon is about 4.65 b.y. The U-238/Pb-204 value estimated for the source of the excess lead in orange soil 74220 is lower than the values estimated for the sources of KREEP (600-1000), high K (300-600) and low K (100-300) basalts. |
| NASA分類 | LUNAR AND PLANETARY EXPLORATION |
| レポートNO | 75N14689
NASA-CR-141253
REPT-222 |
| 権利 | No Copyright |
| URI | https://repository.exst.jaxa.jp/dspace/handle/a-is/191669 |
