Early Moon formation inferred from hafnium–tungsten systematics
Early Moon formation inferred from hafnium–tungsten systematics
复制标题
从铪-钨系统学推断出早期月球的形成
作者：
M. Thiemens;P. Sprung;R. Fonseca;F. Leitzke;C. Münker
月球形成的日期对地球的起源有着重要的限制。月球年龄的估计范围从太阳系形成后的30至200兆尔不等。这场年龄争论的核心是，硅酸盐月球比硅酸盐地球推断出的182W丰度更高。这种成分上的差异被解释为在地核形成后对月球的吸积比对地球的吸积晚的残余。在这里，我们提出了高精度的微量元素组成数据从电感耦合等离子体质谱广泛的月球样品。我们的测量表明，硅酸盐月球的Hf/W比高于硅酸盐地球的体积。通过将这些数据与实验得出的分配系数相结合，我们发现月球样品中过量的182W可以用现已灭绝的182Hf向182W的衰变来解释，182Hf仅在太阳系形成后的前60 Myr存在。我们得出的结论是，月球形成较早，大约比太阳系晚50myr，并且硅酸盐月球的过量182W与晚期吸积无关。根据对月球岩石样本的高精度成分分析，月球形成于太阳系之后的50兆尔左右，表明月球的硅酸盐Hf/W比高于地球。
The date of the Moon-forming impact places an important constraint on Earth’s origin. Lunar age estimates range from about 30 Myr to 200 Myr after Solar System formation. Central to this age debate is the greater abundance of 182W inferred for the silicate Moon than for the bulk silicate Earth. This compositional difference has been explained as a vestige of less late accretion to the Moon than to the Earth after core formation. Here we present high-precision trace element composition data from inductively coupled plasma mass spectrometry for a wide range of lunar samples. Our measurements show that the Hf/W ratio of the silicate Moon is higher than that of the bulk silicate Earth. By combining these data with experimentally derived partition coefficients, we found that the 182W excess in lunar samples can be explained by the decay of the now extinct 182Hf to 182W. 182Hf was only extant for the first 60 Myr after the Solar System formation. We conclude that the Moon formed early, approximately 50 Myr after the Solar System, and that the excess 182W of the silicate Moon is unrelated to late accretion.The Moon formed around 50 Myr after the Solar System, suggests a lunar silicate Hf/W ratio higher than that of Earth, from high-precision compositional analysis of lunar rock samples.
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钛对高场强元素在硅酸盐、氧化物和月球玄武岩熔体之间分配行为的影响及其在海海玄武岩起源中的应用
影响因子：
3.9
作者：
Leitzke;Fonseca;Michely;Sprung;Münker;Heuser;Blanchard
通讯作者：
Blanchard
影响因子：
64.8
作者：
Kruijer, Thomas S.;Kleine, Thorsten;Sprung, Peter
通讯作者：
Sprung, Peter
影响因子：
5.3
作者：
Fonseca, Raul O. C.;Mallmann, Guilherme;Blanchard, Henrik
通讯作者：
Blanchard, Henrik
影响因子：
5.3
作者：
Sprung, Peter;Kleine, Thorsten;Scherer, Erik E.
通讯作者：
Scherer, Erik E.