Hayachine ultramafic complex has been suffered a contact metamorphism. The rocks mainly consist of metamorphic olivine, clinopyroxene, orthopyroxene, serpentine, talc, tremolite, anthophyllite and magnetite. Relict minerals were distinguished from metamorphic minerals. In the northern area of the low metamorphic grade, relict olivine as well as clinopyroxene were found. Chromite is a probable relict mineral appearing throughout the complex. Metamorphic orthopyroxene is found in the area of the highest metamorphic grade, and is enstatite depleted in diopside component. The relict olivines are Fo_89.5-93 and enriched in NiO, whereas the metamorphic olivines in the low grade (up to Fo_96.5) are depleted in NiO. In the high grade area in the south of the complex, the metamorphic olivine (Fo_90-93.5) are enriched in NiO as much as the relict olivine. The metamorphic diopside is extremely poor in Cr₂O₃ and Al₂O₃. The relict diopsides are more enriched in the both elements than the metamorphic ones, but they are less enriched in wollastonite component than the metamorphic ones.

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Various phosphatic and carbonate rocks are intercalated within black shale of the Upper Permian Toyoman Series. They are divided into four types on the basis of their occurrence and lithology, i. e., 1) nodule, 2) A type: phosphate bearing calcareous shale, 3) B type: coarse grey coloured carbonaceous sandstone, 4) C type: massive greyish sparitic limestone. Petrological and chemical features of four types are transitional with each other. Phosphate is dominant in the nodules and A type rocks, while carbonate is dominant in B and C type rocks. The analytical results of these rocks show the following characteristics: P₂O₅ and F contents of analysed rocks have wide ranges from 17.73 to 0.09% and 14, 000 to 85 ppm, respectively. Strong correlations between P₂O₅-F, FeO^* (total iron as FeO)-MgO, CaO-CO₂, and MnO-CaO are worthy of note. Phosphate-rich rocks are composed mainly of cryptocrystalline fluorapatite. Carbonate in all types contain several% of MnCO₃ as solid solution. Judging from an important role of upwelling, the existence of sedimentary phosphatic rocks and Mn-rich carbonate rocks indicates that the sedimentary environments of the Toyoman Series were not a closed inland sea, but a continental shelf or slope.

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Haga granitic complex is one of a series of the late Cretaceous to early Paleogene graniticintrusions widely distributed in the San'in belt of the Southwest Japan. Haga granitic complex consists of three plutons, namely, the east, the west and the north plutons. These plutons intruded into Paleozoic-Mesozoic formations including Cretaceous volcanic rocks successively from the east pluton to north pluton.
The east pluton is composed of four concentrically arranged units, the outer unit consisting of tonalite, intermediate one of granodiorite-tonalite, and the central one of granodiorite and adamellite. The west pluton also can be divided into three units arranged concentrically, namely, granodiorite, granodiorite-adamellite and adamellite. The north pluton is composed of aplitic granite and granophyre.
Chemical compositions of the rocks and their constituent minerals were determined. The amount of major elements of the rock units varies linearly following the SiO₂ content and the compositions of clinopyroxene, hornblende and biotite represent no change through the east and the west plutons. Chemical compositions of plagioclase and alkali feldspar vary systematically with the SiO₂ content of the host rock. And, these plutons belong to magnetite series. From above features, it is considered that the east and the west plutons were derived from the parental magma. On the other hand, the north pluton belongs to ilmenite series. The north pluton intrudes into the east pluton very clearly. The north pluton should be derived from another magma. The occurrence and chemistry of clinopyroxene indicate these plutons intruded in the shallow levels of the crust. Based on the chemical compositions of magnetite and ilmenite pair and plagioclase and alkali feldspar pair, it is concluded that crystallization of the east and the west pluton proceeded under considerably low temperature and oxidation condition.
The cause of the zoned plutons is thought to be crystallization differentiation. Namely, the differentiated acid magra moves inward with the progress of differentiation, leaving behind the basic outer rock unit.

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