愛媛県大野山地域の秩父帯の地質構造

Geological structures of the Chichibu Terrain in the Onoyama Area, Ehime Prefecture, are reexamined. Yamakita (1998) and Matsuoka et al. (1998) considered that there is the Kurakawa syncline with horse-shoe shape distributions of cherts in the northern Chichibu Terrain, and that strata of the northern half of the northern Chichibu Terrain dip toward south. However, the syncline does not occur, because there are no horse-shoe shape distributions and because the strata of the northern Chichibu Terrain dip toward north fundamentally. Strata consisting of phyllites with cherts, greenstones and limestones near Mt. Onoyama do not occur as a window, but occur as the hanging wall of the Onoyama thrust. The Uonashi thrust occurs at the southwestern margin of the Permian limestone near Tojikano. The thrust does not extend toward north, and does not displace the Mikabu Greenstones, because it is cut by the Onoyama thrust.