抄録
In northwestern part of Honshu, Tertiary granitoids with 13.9 to 6.0 Ma age data, that is thought to be in a period of vein type mineralization, show the intermittent distributions in NE-SW and NW-SE trend. It suggests that the granitoids intruded along shear zones formed by common maximum compressive stress in E-W trend. Veins are hosted in E-W, NE-SW, NW-SE trending normal and reverse faults, NE-SW trending right lateral faults and E-W trending extension fractures. The normal and reverse faults were formed by intrusions of the granitoids and propylite. These might be re-opened fractures after being formed by the regional stress field based on their strikes. The right lateral faults in the propylite and extension fractures in the granitoids and propylite were formed by the regional stress field after the intrusive activities.
