Kleine Thorsten, Palme Herbert, Mezger Klaus, Halliday Alex N
Zentrallabor für Geochronologie, Institut für Mineralogie, Corrensstrasse 24, D-48149 Münster, Germany.
Science. 2005 Dec 9;310(5754):1671-4. doi: 10.1126/science.1118842. Epub 2005 Nov 24.
The use of hafnium-tungsten chronometry to date the Moon is hampered by cosmogenic tungsten-182 production mainly by neutron capture of tantalum-181 at the lunar surface. We report tungsten isotope data for lunar metals, which contain no 181Ta-derived cosmogenic 182W. The data reveal differences in indigenous 182W/184W of lunar mantle reservoirs, indicating crystallization of the lunar magma ocean 4.527 +/- 0.010 billion years ago. This age is consistent with the giant impact hypothesis and defines the completion of the major stage of Earth's accretion.
铪 - 钨计时法用于测定月球年代受到了限制，主要是因为月球表面钽 - 181通过中子俘获产生宇宙成因钨 - 182。我们报告了月球金属的钨同位素数据，这些数据中不包含源自钽 - 181的宇宙成因钨 - 182。这些数据揭示了月球地幔储层中原生钨 - 182/钨 - 184的差异，表明月球岩浆海洋在45.27±0.10亿年前结晶。这个年代与巨碰撞假说一致，并确定了地球吸积主要阶段的完成。
