Late Mesozoic Crustal Movements in the Hida Plateau, Central Honshu, Japan

In the Hida Plateau region, the Hida gneiss complex on the north side and the Paleozoic system of the Yamaguchi facies on the south side constitute the autochthonous basement. The Tetori basin was formed on the southern margin of the Hida complex, and into this basin were supplied the materials from the north. Thus, the Jurassic Kuzuryu group was deposited first, followed by the mainly Lower Cretaceous Itoshiro group. Afterwards, the Upper Cretaceous Omodani rhyolites were thickly accumulated on the level denudation surface, preceeded by the deposition of the Asuwa group in the small depressions which had come into existence in the early period of accumulation of the Omodani rhyolites. Since Middle Jurassic the crustal movements proceeded intermittently, and culminated during the period from Mid-to Latest Cretaceous. Deformations, accompanied by intense thrusting, took place along with the severe volcanic activities of acid and intermediate rocks which is followed by the intrusion of Early Tertiary granites. The main thrust faults can be classified into two groups; the Ura-Nippon thrust system extending on the north to northeast side, and the Omote-Nippon system which trends on south to southeast side. The thrust sheets of the former are composed of the Hida complex, whereas those of the latter consists of the Paleozoic system of the Para-Akiyoshi facies, which comprises Silurian, Devonian, Carboniferous and various Permian sediments. The main thrust faults were completed in Latest Cretaceous