In recent years, many studies has been reported in physic journals concerning the ion-beam analysis of the trace elements and light elements using accelerator induced MeV-range high energy ion-beam. A high-energy ion beam bombardment on a target materialinduces many types of emission of particles and radiations. The detection of these emissions make possible a wide variety of analytical methods. These ion-beam analyses, e.g. PIXE (Proton induced X-ray emission), RBS(Ruatherford backscattering spectrometry), NRA (Neutron reaction analysis), PIGE (Proton induced gamma-ray, emission), PAA (Proton activation analysis), have many advantages in comparison with electron beam probe analytical methods. These ion-beam analyses (IBA) also has unique capabilities for trace element analysis, light element analysis, depth profile analysis, external beam analysis, channeling analysis, ion beam induced luminescence, subsurface fluid inclusion analysis and accelerator mass spectroscopy. These analytical methods are suitable for the mineral science related materials although the application on the mineral science is not yet made in Japan. In view of this situation, the basis of each analytical technique and recent progress on mineralogical applications are reviewed.

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An understanding of the rate and mechanism of water/rock interactions is important to clarify the mass transport processes at the surface and in the shallow part of the earth's crust. Mineral dissolution into aqueous solution is one of the elementary processes and often plays a rate-controlling role in the mass transport. Studies on the mineral dissolution are reviewed from the kinetic point of view. Solution chemistry studies have provided a lot of dissolution rate constants and surface speciation data. They have clarified correlations between dissolution rates and mineral structures, whereas the rate data are not in good agreement with field rate data. Surface analysis techniques such as secondary ion mass spectroscopy (SIMS), X-ray photoelectron spectroscopy (XPS), and resonant nuclear reaction analysis (RNRA) have proved the existence of hydrogen rich and cation depleted surface layers with a thickness less than 1μm. Recently developed atomic force microscopy (AFM) enables us to carry out an in situ observation of the surface dissolution and precipitation process in atomic scale. The combination of these techniques as well as simulation studies will lead us to an make integrated and quantitative mineral dissolution model.

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Mechanisms and P-T dependence of thermal conductivity and diffusivity of minerals are reviewed. There are three heat transfer mechanisms: lattice, radiative and electric heat transfers. Lattice and radiative heat transfers are very important to the thermal regime in the mantle. Thermal diffusivity is an essential physical quantity to lattice heat transfer, whereas thermal conductivity is to radiative one. The mean free path of the particles carrying heat is the most important factor to discuss both thermal conductivity and diffusivity. In the case of lattice heat transfer, the mean free path is limited by the anharmonicity of lattice vibrations. Since the effect of the anharmonicity is approximately proportional to the absolute temperature, thermal diffusivity is inversely proportional to it. On the contrary, thermal diffusivity increases with increasing pressure, because the increase of pressure slightly decreases the effect of anharmonicity. The radiative heat transfer increases with increasing temperature according to the Stephan-Bolzmann's law. Because of the shortening of the mean free path of photon with increasing temperature, however, the radiative heat transfer increases in the smaller rate than T⁴. The pressure dependence of the radiative heat transfer may be negative.

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Species of uranyl ions as well as secondary uranium minerals are affected by the geochemical environments at the surface of the Earth. In other words, the evolution of secondary uranium minerals can provide us various information on the geochemical environments for a better understanding of geochemical processes involving migration behavior of elements. The author reviews geochemistry of uranyl ions and crystal chemistry of uranium minerals, and shows the evolution of secondary uranium minerals at some uranium deposits including Oklo, Cigar Lake, Shinkolobwe and Koongarra. The primary uraninites are altered by oxidizing conditions at the latter two deposits, and by reducing conditions at the former two deposits, which result in different types of evolution of secondary uranium minerals.

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