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Nakada, R., Usui, T., Ushioda, M., Takahashi, Y. (2020) Vanadium micro-XANES determination of oxygen fugacity in olivine-hosted glass inclusion and groundmass glasses of martian primitive basalt Yamato 980459. American Mineralogist. 105, 1695–1703. [Link]
Ramirez, R. M, Craddock, R. A., and Usui, T. (2020) Climate simulation of early Mars with estimated precipitation, runoff, and erosion rates. Journal of Geophysical Research–Planets, doi:10.1029/2019JE006160. [Link] [ELSI press release, EN & JP] [Many Worlds]
Zacny, K et al. (incl. Usui, T.) (2020) Pneumatic Sampler (P-Sampler) for the Martian Moons eXploration (MMX) Mission. In 2020 IEEE Aerospace Conference, pp. 1-11. IEEE. doi: 10.1109/AERO47225.2020.9172470 [Link].
Usui, T. (2019) Hydrogen reservoirs in Mars as revealed by Martian meteorites, in “Volatiles In The Martian Crust” (Eds. Filiberoto J. and Schwenzer S. P.), Elsevier. [Link]
Usui, T. (2019) What Geology and Mineralogy Tell Us About Water on Mars, in "Astrobiology" (Eds. A. Yamagishi, T. Kakegawa and T. Usui), Springer. [Link]
*Hyodo, R., Kurosawa, K., Genda, H., Usui, T. and Fujita, K. (2019) Transport of impact ejecta from Mars to its moons as a means to reveal Martian history. Scientific Reports. 9, 19833. doi:10.1038/s41598-019-56139-x [Open Access]
*Kagami, S., Haba, K. M., Yokoyama, T., Usui, T. , Greenwood, R. C. (2019) Geochemistry and Sm‐Nd chronology of a Stannern‐group eucrite, Northwest Africa 7188, Meteoritics & Planetary Science, doi: 10.1111/maps.13382 [Link]
Jia, T. Z., Chandru, K., Hongo, Y., Afrin, R., Usui, T. Myojo, K., and Cleaves, H. J. (2019) Membraneless polyester microdroplets as primordial compartments at the origins of life. Proceedings of the National Academy of Sciences. doi: 10.1073/pnas.1902336116. [Link] [Tokyo Tech Press release] [EurekAlart!]
Lawrence et al. (incl. Usui, T.) (2019) Measuring the Elemental Composition of Phobos: The Mars‐moon Exploration with GAmma rays and NEutrons Investigation for the Martian Moons eXploration Mission, Earth and Space Science, doi: 10.1029/2019EA000811. [Link]
DW Beaty et al. (incl. Usui, T.) (2019) The potential science and engineering value of samples delivered to Earth by Mars sample return, Meteoritics & Planetary Science, 54, S3-152. [Link]
Usui, T. (2018) Scientific Significance and Strategy of Mars Subsurface Exploration. Yuseijin, 27, 296-301.
*Koike, M., Moriwaki, R. and Usui, T. (2018) Current and future contributions of martian meteorites to Mars science. Yuseijin, 27,180-189. [Link]
*Nakanishi, N., Yokoyama, T., Okabayashi, S., Usui, T. and Iwamori, H. (2018) Re-Os isotopic systematics and fractionation of siderophile elements in metal phases from CBa chondrites. Meteoritics and Planetary Science, 53, 1051-1065 [Link]
Yoshimura, Y. et al. (incl.Usui, T.) (2018) Development of Life Detection Microscope (LDM) for life search on Mars. Yuseijin, 27,147-141. [Link]
Kuramoto, K., (incl. Usui, T.) (2018) Martian Moons eXploration MMX elucidating the formation of habitable planets in the solar system. Yuseijin, 27, 207-215. [Link]
Greenwood, J. P., Karato, S., Vander Kaaden, K. E., Pahlevan, K., and Usui, T. (2018) Water and Volatile Inventories of Mercury, Venus, the Moon, and Mars. Space Science Reviews. 214, 92. [Link]
Kurokawa, H., Foriel, J., Laneuville, M., Houser, C., and Usui, T. (2018) Subduction and atmospheric escape of Earth's seawater constrained by hydrogen isotopes. Earth and Planetary Science Letters 497, 149-160 [Link]
Kurokawa, H., Kurosawa, K. and Usui, T. (2018) A lower limit of atmospheric pressure on early Mars inferred from nitrogen and argon isotopic compositions. Icarus, 299, 443-459. [Link]
Yamagishi, A. et al. (incl. Usui, T.) (2018) LDM (Life Detection Microscope): In situ imaging of living cells on surface of Mars. The 31st ISTS Special Issue of Transaction of JSASS, Aerospace Technology Japan, 16, 299-305 [Link]
Usui, T. (2017) Martian water stored underground. Nature, 552, 339-340. [Link]
*Moriwaki, R., Usui, T., Simon, J.I., Jones, J.H., Yokoyama, T. and Tobita, M. (2017) Coupled Pb isotopic and trace element systematics of Tissint meteorite: geochemical signatures of the depleted shergottite source mantle. Earth and Planetary Science Letters, 474, 180-189. [Link]
*Fukami, Y., Tobita, M., Yokoyama, T., Usui, T. and Moriwaki, R. (2017) Precise isotope analysis for sub-nanogram lead by total evaporation thermal ionization mass spectrometry (TE-TIMS) coupled with 204Pb-207Pb double spike method. Journal of Analytical Atomic Spectrometry, 32, 848-857.
*Tobita, M., Usui, T., Yokoyama, T. (2017) New constraints on shergottite petrogenesis from analysis of Pb isotopic compositional space: implications for mantle heterogeneity and crustal assimilation on Mars. Geochemical Journal. 51, 81-94.
Kitadai, N., Oonishi, H., Umemoto, K., Usui, T., Fukushi, K. and Nakashima, S. (2017) Glycine polymerization on oxide minerals. Origins of Life and Evolution of Biospheres, DOI: 10.1007/s11084-016-9516-z.
Ehlmann, B. L. et al. (incl. Usui, T.) (2016) The sustainability of habitability on terrestrial planets: insights, questions, and needed measurements from Mars for understanding the evolution of Earth-like worlds. Journal of Geophysical Research-Planets, 121, DOI: 10.1002/2016JE005134. [Open Access] [Top-10 most downloaded paper in 2016-2017 JGR]
Kurokawa, H., Usui, T. and Sato, M. (2016) Interactive evolution of multiple water-ice reservoirs on Mars: Insight from hydrogen isotope compositions. Geochemical Journal, 50, 67–79. DOI:10.2343/geochemj.2.0407. [Open Access]
Miyamoto, H., Komatsu, G., Dohm, J., Hammi, R., Usui, T., and Yamagishi, A. (2016) Geomorphological view of the environmental history and candidate habitable environments on Mars. Journal of Geography, 125, 171-184. DOI:10.5026/jgeography.125.171.
Usui T., Alexander C. M.O'D., Wang J., Simon J. I., and Jones J. H. (2015) Meteoritic evidence for a previously unrecognized hydrogen reservoir on Mars. Earth and Planetary Science Letters 410, 140-151. [Link] [Top-rated article in EPSL] [NASA press release]
Usui T., Jones J. H., and Mittlefehldt D. W. (2015) A partial melting study of an ordinary (H) chondrite composition with application to the unique achondrite Graves Nunataks 06128 and 06129. Meteoritics & Planetary Science 50, 759-781. [Link]
*Peters, T. J., Simon, J. I., Jones, J. H., Usui, T., Moriwaki, R., Economos, R. C., Schmitt, A. K., and McKeegan, K. D. (2015) Tracking the source of the enriched martian meteorites in olivine-hosted melt inclusions of two depleted shergottites, Yamato 980459 and Tissint. Earth and Planetary Science Letters 418, 91–102. [Link]
*Asaah, A.N.E., T. Yokoyama, F.T. Aka, T., Usui, T., Kuritani, M.J. Wirmvem, H. Iwamori, E.M. Fozing, J. Tamen, G.Z. Mofor, T. Ohba, G. Tanyileke, and J.V. Hell. (2015) Geochemistry of lavas from maar-bearing volcanoes in the Oku Volcanic Group of the Cameroon Volcanic Line. Chemical Geology 406, 55-69. [Link]
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Usui T. and Miyamoto H. (2014) Toward Future Mars Exploration Missions: Our Heritage and New Challenges. Chikyu Kagaku. 48, 221‒230.
Kurokawa H., Sato M., Ushioda M., Matsuyama T., Moriwaki R. Dohm, J. M., and Usui, T. (2014) Evolution of Water Reservoirs on Mars: Constraints from Hydrogen Isotopes in Martian Meteorites. Earth and Planetary Science Letters 394, 179-185. [Link]
Usui, T. and Iwamori, H. (2013) Mixing relations of the howardite-eucrite-diogenite suite: a new statistical approach of independent component analysis for the Dawn mission. Meteoritics & Planetary Science 48, 2289-2299.
Usui T., Alexander C. M.O'D., Wang J., Simon J. I., and Jones J. H. (2012) Origin of water and mantle–crust interactions on Mars inferred from hydrogen isotopes and volatile element abundances of olivine-hosted melt inclusions of primitive shergottites. Earth and Planetary Science Letters 357-358, 119-129. [Link] [NASA press release]
Namiki N, Komatsu G, and Usui T. et al. (2012) A proposal for rover geological exploration on Mars. The Journal of the Geological Society of Japan 118, 606-617.
Usui T. (2011) New views of Mars: Reviews of recent Mars explorations and meteorites studies. Chikyu Kagaku. 45, 159-173.
Usui T., Sanborn M., Wadhwa M., and McSween H. Y. (2010). Petrology and trace element geochemistry of Robert Massif 04261 and 04262 meteorites, the first examples of geochemically enriched lherzolitic shergottites. Geochimica et Cosmochimica Acta 74, 7283-7306.
Usui T., McSween H. Y., Mittlefehldt D. W., and Prettyman T. H. (2010). K-Th-Ti systematics and new three-component mixing model of HED meteorites: Prospective study for interpretation of gamma-ray and neutron spectra for the Dawn mission. Meteoritics & Planetary Science 45, 1170-1190.
Usui T., McSween H. Y., and Clark B. C. III. (2008). Petrogenesis of high-phosphorous Wishstone-class rocks in Gusev crater, Mars. Journal of Geophysical Research–Planets 113, E12S44, doi:10.1029/2008JE003225.
Usui T., McSween H. Y., and Floss C. (2008). Petrogenesis of olivine-phyric shergottite Yamato-980459, revisited. Geochimica et Cosmochimica Acta 72, 1711-1730.
Usui T. and McSween H. Y. (2007). Geochemistry of 4 Vesta based on HED meteorites: Prospective study for interpretation of gamma ray and neutron spectra for the Dawn mission. Meteoritics & Planetary Science 42, 269–283.
Usui T., Kobayashi K., Nakamura E., and Helmstaedt H. (2007). Trace element fractionation in deep subduction zones inferred from a lawsonite-eclogite xenolith from the Colorado Plateau. Chemical Geology 239, 336-351.
Kuritani T., Usui T., Yokoyama T., and Nakamura E. (2006). Accurate isotopic and concentration analyses of small amounts of Pb using isotope dilution coupled with the double spike technique. Geostandards and Geoanalytical Research 30, 209-220.
Usui T., Nakamura E., and Helmstaedt H. (2006). Petrology and geochemistry of eclogite xenoliths from the Colorado Plateau: Implications for the evolution of the subducted oceanic crust. Journal of Petrology 47, 929–964.
Usui T., Nakamura E., Kobayashi K., Maruyama S., and H. Helmstaedt (2003). Fate of the subducted Farallon plate inferred from eclogite xenoliths in the Colorado Plateau. Geology 30, 589-592.
Usui T., Kobayashi K, and Nakamura E. (2002). U-Pb isotope systematics of micro-zircon inclusions: Implications for the age and origin of eclogite xenolith from the Colorado Plateau. Proceedings of the Japan Academy 78, 51-56.