On the Granitic rocks in Chugoku, and the molybdenite and wolframite deposits in them

The Chūgoku district is characterized by a vast exporsure of granitic intrusive rocks. The two types of granites, i.e. Rǒyke and Chūgoku granites are distinguished in them. According to the mineral deposits contained in the granitic rocks, the present author proposed to divide the area occupied by Chūgoku granite in two provinces, the San-in granite province and the Hiroshima granite province. The San-in granite province occupies the northern part of the Chūgoku district, and is characterized by hydrothermal or meso-thermal molybdenite and sericite deposits. Famous molybdenite deposits are swarmed in the middle part of the granite exposure. In the province it may be probable that the hood or summit part of the granitic batholith are not much eroded away. The Hiroshima granite province occupies the main part of the Chūgoku district and is characterized by pneumatolytic and hydrothermal or hypothermal wolframite deposits, and great pegmatite deposits. These deposits are distributed along the peripheral zone of the province, re-maining a vast barren central core. In the province the hood or summit part of the batholith may have been almost eroded away. Each of the two provinces constitutes of its own small metallogenetic province, and exhibits eminent discontinuous character at the boundary between the two