Details
Original language | English |
---|---|
Pages (from-to) | 84-87 |
Number of pages | 4 |
Journal | SCIENCE |
Volume | 301 |
Issue number | 5629 |
Publication status | Published - 4 Jul 2003 |
Externally published | Yes |
Abstract
It has been assumed that Nb and Ta are not fractionated during differentiation processes on terrestrial planets and that both elements are lithophile. High-precision measurements of Nb/Ta and Zr/Hf reveal that Nb is moderately siderophile at high pressures. Nb/Ta values in the bulk silicate Earth (14.0 ± 0.3) and the Moon (17.0 ± 0.8) are below the chondritic ratio of 19.9 ± 0.6, in contrast to Mars and asteroids. The lunar Nb/Ta constrains the mass fraction of impactor material in the Moon to less than 65%. Moreover, the Moon-forming impact can be linked in time with the final core-mantle equilibration on Earth 4.533 billion years ago.
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In: SCIENCE, Vol. 301, No. 5629, 04.07.2003, p. 84-87.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Evolution of planetary cores and the Earth-Moon system from Nb/Ta systematics
AU - Münker, Carsten
AU - Pfänder, Jörg A.
AU - Weyer, Stefan
AU - Büchl, Anette
AU - Kleine, Thorsten
AU - Mezger, Klaus
PY - 2003/7/4
Y1 - 2003/7/4
N2 - It has been assumed that Nb and Ta are not fractionated during differentiation processes on terrestrial planets and that both elements are lithophile. High-precision measurements of Nb/Ta and Zr/Hf reveal that Nb is moderately siderophile at high pressures. Nb/Ta values in the bulk silicate Earth (14.0 ± 0.3) and the Moon (17.0 ± 0.8) are below the chondritic ratio of 19.9 ± 0.6, in contrast to Mars and asteroids. The lunar Nb/Ta constrains the mass fraction of impactor material in the Moon to less than 65%. Moreover, the Moon-forming impact can be linked in time with the final core-mantle equilibration on Earth 4.533 billion years ago.
AB - It has been assumed that Nb and Ta are not fractionated during differentiation processes on terrestrial planets and that both elements are lithophile. High-precision measurements of Nb/Ta and Zr/Hf reveal that Nb is moderately siderophile at high pressures. Nb/Ta values in the bulk silicate Earth (14.0 ± 0.3) and the Moon (17.0 ± 0.8) are below the chondritic ratio of 19.9 ± 0.6, in contrast to Mars and asteroids. The lunar Nb/Ta constrains the mass fraction of impactor material in the Moon to less than 65%. Moreover, the Moon-forming impact can be linked in time with the final core-mantle equilibration on Earth 4.533 billion years ago.
UR - http://www.scopus.com/inward/record.url?scp=2142730588&partnerID=8YFLogxK
U2 - 10.1126/science.1084662
DO - 10.1126/science.1084662
M3 - Article
C2 - 12843390
AN - SCOPUS:2142730588
VL - 301
SP - 84
EP - 87
JO - SCIENCE
JF - SCIENCE
SN - 0036-8075
IS - 5629
ER -