Research Projects

Apr, 2014 - Mar, 2017

Revealing the process of melt generation and hidden reservoir formation in the Hadean Earth

Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)  Grant-in-Aid for Scientific Research (C)

Grant number
26400514
Japan Grant Number (JGN)
JP26400514
Grant amount
(Total)
4,680,000 Japanese Yen
(Direct funding)
3,600,000 Japanese Yen
(Indirect funding)
1,080,000 Japanese Yen

The present Earth has a higher 142Nd/144Nd ratio than most chondrites. Thus, if the Earth is assumed to have formed from chondrite, a complement low-142Nd/144Nd reservoir (hidden reservoir) is needed. We estimated the age and conditions to form the hidden reservoir based on Sm-Nd partitioning and melting phase relations. Our estimate indicates that the hidden reservoir should have formed within ~30 Myr from the Earth formation and at 7 GPa, 1750°C. We then performed high pressure melting experiments on primitive peridotite to determine the major element composition of a melt that can be the hidden reservoir at this condition, and calculated its density. The results indicate that the melt is iron- and titanium-rich komatiite. The estimated density of the melt is lower than that of the primitive peridotite, suggesting that the melt would have ascended in the mantle to form crust in the Hadean and have been ejected from the Earth by the giant impact.

Link information
URL
https://kaken.nii.ac.jp/file/KAKENHI-PROJECT-26400514/26400514seika.pdf
KAKEN
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-26400514
ID information
  • Grant number : 26400514
  • Japan Grant Number (JGN) : JP26400514

List of results of the research project

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Papers

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