Yokoyama Laboratory investigates origin and evolution of the early solar system materials by isotopic and elemental analysis of terrestrial and extraterrestrial mateterials.

1/1/2020 A new postdoc, Dr. Ikshu GAUTAM, has joined our group!

6/14/2019 Dr. Haba published a new paper in Nature Geoscience regarding a new model for the evolutionary history of Vesta.


Tokyo Tech News


Yokoyama, T., Fukai, R., Nakahara, M.

Separation of heavy lanthanoids by flash column chromatography for precise determination of Er and Yb isotope compositions in rock samples.
Geostandards and Geoanalytical Research, in press.

Moriwaki, R.., Usui, T., Tobita, M., Yokoyama, T.

Geochemically heterogeneous Martian mantle inferred from Pb isotope systematics of depleted shergottites.
Geochimica et Cosmochimica Acta, in press.

Okabayashi, S., Yokoyama, T., Hirata, T., Terakado, K., Galimov, E.M.

Iron isotopic signature in Luna 16, 20, 24 soils: Effect of space weathering and Fe isotopic composition of very low-Ti basalt.
Geochimica et Cosmochimica Acta, 2020. 269, 1-14.

Asaah, A.N.E., Yokoyama, T., Aka, F.T., Kuritani,T., Iwamori, H., Usui, T., Gountie, M.D., Tamen, J., Hassegawa, T., Fozing, T.E.M., Nche, A.L.

Major/trace elements and Sr-Nd-Pb isotope systematics of lavas from Lakes Barombi Mbo and Barombi Koto in the Kumba graben, Cameroon Volcanic Line: Constraints on petrogenesis.
Journal of African Earth Science, 2020. 161, 103675 (14 pp).

Yokoyama, T., Nagai, Y., Fukai, R., Hirata, T.

Origin and evolution of distinct Mo isotopic variabilities within carbonaceous and non-carbonaceous reservoirs.
Astrophys. J., 2019. 883, 62 (23pp). doi: 10.3847/1538-4357/ab39e7

Kagami, S., Haba, M.K., Yokoyama, T., Usui, T., Greenwood, R.C.

Geochemistry and Sm-Nd chronology of a Stannern trend eucrite, Northwest Africa 7188.
Meteoritics & Planetary Science, 2019. 54, 2710-2728. doi: 10.1111/maps.13382