Nishida Prize

Atsushi Okamoto


Research on the water-rock interaction within the Earth’s interior and the development of rock texture

A list of five major papers

  • Amagai, T., Okamoto, A., Niibe, T., Hirano, N., Motomiya, K., Tsuchiya, N., 2019. Silica nanoparticles produced by explosive flash vaporization during earthquakes. Scientific Reports, 9, 9738.
  • Okamoto, A., Shimizu, H., 2015. Contrasting fracture patterns induced by volume-increasing and -decreasing reactions: implications for the progress of metamorphic reactions. Earth and Planetary Science Letters, 415, 9-18.
  • Okamoto, A., Ogasawara, Y., Tsuchiya, N., 2011. Progress of hydration reactions in olivine–H2O and orthopyroxenite–H2O systems at 250 °C and vaporsaturated pressure. Chemical Geology, 289, 245-255.
  • Okamoto, A., Tsuchiya N., 2009. Velocity of vertical fluid ascent within veinforming fractures. Geology, 37, 563-566.
  • Okamoto, A., Toriumi, M., 2005. Progress of actinolite-forming reactions in mafic schists during retrograde metamorphism: An example from the Sanbagawa metamorphic belt in central Shikoku, Japan. Journal of Metamorphic Geology, 23, 335-356.

Major achievements

Atsushi Okamoto has specialized in petrology and hydrothermal reaction science, and has been developing research on various fluid-rock interactions in the earth’s interior such as metamorphism in subduction zones, metasomatism, alteration and dissolution/precipitation phenomena in crust and mantle. Besides, he has conducted various hydrothermal reaction experiments using original equipments, such as metasomatic reaction between crustal-mantle boundary, nanoparticle formation by flushing of supercritical fluids, and synthesis of artificial mineral filling veins, as a research fusion of science and engineering with the view of development of supercritical geothermal resources. Recently, he has developed a new geomaterial reaction science that links rock pattern formation and dynamic reaction processes through numerical modeling of coupled reaction-fracturing-fluid flow and kinetic analysis using data-driven approaches. These various studies have been highly evaluated internationally for the creation of new petrology to understand dynamic aspects of solid earth reactions from the viewpoint of rock-water interactions and rock microstructures.