Moderate amounts of data on the Jurassic granitoids in the Hida belt and South Korea have been accumulated. From the data presented, it will be seen that similarities and disssimilarities of the Jurassic granitoids between two regions. 1) Modal compositions of Jurassic granitoids are somewhat similar between the two regions; 2) radiometric ages, series, such as magnetite-and ilmenite series, initial strontium ratios, and REE patterns of the Jurassic granitoids between the two regions are different. The facts mean that source materials and genesis of the Jurassic granitoids between the two regions were different. The REE patterns suggest that the Jurassic granitoids of South Korea were derived by partial melting of lower crust or by fractional crystallization of hornblende from quartz dioritic magmas, whereas Jurassic granitoids in the Hida belt were mainly differentiated by the insitu fractional crystallization. From the difference in the initial strontium ratios between the two regions, it is suggested that the Jurassic granitoids in South Korea may have been situated in the continental side compared with the Jurassic granitoids in the Hida belt.

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D/H ratios of ten sericites from the Kamioka Zn-Pb skarn deposits and three pottery stone deposits nearby are measured. Their δD values are in the range from -100 to -120‰ (SMOW). Considering the fractionation between sericites and water at temperatures below 300°C, δD values of hydrothermal solutions responsible for the formation of these deposits are calculated to be about -70 to -90‰. These δD values are in harmony with the genetic hypothesis for the Kamioka deposits, which proposes a huge convective circulation of solutions of meteoric water origin at the time of latest Cretaceous.

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The mineralization age of the Kamioka Pb-Zn skarn deposit in the Hida terrain was examined on the basis of K-Ar age data. Hastingsite skarn occurring in the central part of the zonal arrangement of the deposit was dated at 63.3 Ma, equivalent to the ages of Shiroji (63.8-67.5 Ma for sericites; NAGASAWA and SHIBATA, 1985), high grade Pb-Zn ore on the margins of the deposit. The Kamioka deposit is concluded to have formed in a period from the late Cretaceous to the early Paleogene. Igneous and metamorphic rocks around the deposit are of Triassic to Jurassic age, but K-feldspar samples give young and various ages (56-162 Ma) due to Ar-loss at the time of mineralization. Although the igneous rocks related to the mineralization in the Kamioka area have not yet been identified, a negative gravity anomaly implies a large mass of acidic intrusive rocks beneath this area.

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The Hida complex is made up mainly of gneisses and granitic rocks. The latters are classified into three ma-jor groups; older migmatitic granitoids, early Mesozoic granitoids and late Cretaceous to Paleogene granitoids. The first group is characterized by, the close association with gneisses forming migmatite structure, metamorphic texture, CaO-rich bulk chemistry, very low magnetic susceptibility, and high initial Sr isotopic ratios. Their isotopic ages range from 400 to 1200 Ma, but the exact age has not yet been obtained.
The second group is the most widespread granitoids in the complex, and its formation is divided into two stages. The early-stage granitic masses, probably 210 to 220 Ma in ages, are composed mainly of weakly foliated quartz monzodiorite to granodiorite and augen granites showing highly mylonitic nature. They include low microcline with nearly maximurn ordering, and exhibit high magnetic susceptibility on the felsic facies and have scattered initial Sr isotopic ratios. The later-stage masses, mostly 180 Ma in ages, comprise zoned plutons composed mainly of tonalite and granodiorite. They contain intermediate microcline with broad x-ray diffraction patterns, and belong to the I-type and magnetite-series granites.
The third group intrudes into the eastern and western sides of the Hida complex, accompanied with felsic volcanic rocks of nearly same geologic ages. The granitoids contain orthoclase with Δ=0, and their petrographic characteristics suggest rapid cooling of the bodies at shallow depth.
The geologic and genetic features of each granitic mass are summarized here, along the above line of classifications.

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Molybdenites occurring in Paleogene granitoids of the Northern Japan Alps of the Hida Mountains were analyzed for δ³⁴S CDT at seven localities. The sulfur isotopic ratios vary from 3.0 to 6.4‰, which are within the range of ore molybdenites from the magnetite-series granitic terrane of the Sanin district, indicating that the Hida Mountains and Sanin district belong to the same metallogenic province. Porphyry-type molybdenite from the Kamioka lead-zinc mine has the δ³⁴S value of 1.4‰. Sulfur of the molybdenite is not derived from the Jurassic Funatsu granitoids but brought up by the latest Cretaceous ilmenite-series magma, prior to the main Paleogene magnetiteseries magmatism.

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