八溝山系の地質と足尾帯の構造

概要

論文の詳細を見る
The Yamizo Group, which occupies the Yamizo Mountains, consists mainly of sandstone, slate and chert, and intercalates small lenses of limestone, thin beds of tuff and conglomerate. The Yamizo Group belonging to the Ashio Belt, which is a geotectonic unit corresponding to the Minoor Tanba Belt in the Inner Zone of Southwest Japan, is of geosynclinal origin and contains many conodonts of the Triassic type almost all over the area. The Ashio Belt and the geosyncline of Southwest Japan are separated from the geosyncline of Northeast Japan by the Tanakura Tectonic Line or the Abukuma Belt, which played a role of tectonic mountains or uplifted belt. The general trend of the Ashio Belt is NNW to SSE as shown in Figs. 2 and 3, and it is nearly parallel to the Tanakura Tectonic Line and the trend of the Abukuma Belt, composed of Takanuki-Gosaisho metamorphic rocks and granitic rocks. Geotectonically the Ashio Belt in Southwest Japan is in parallel arrangement to the Abukuma Belt in Northeast Japan, and the Tanakura Tectonic Line forms the boundary between the two, confronted with each other. The geologic structure of the Kanto district including the Ashio and Yamizo Mountains was affected by acute bending of the southern Fossa Magna, and the Ashio Belt extends northward to the Sea of Japan, its direction being turned under the eastern Kanto Plain. The inner side of the Honshu geosyncline west of the Tanakura Tectonic Line extends not to Northeast Japan along the Honshu Arc, but to the Sea of Japan across the arc obliquely. The mentioned fact is an interesting problem from the standpoint of tectonic geology and paleogeography of the Japanese Islands.
日本地質学会の論文
1976-12-30

八溝山系の地質と足尾帯の構造

スポンサーリンク

概要

著者

関連論文

スポンサーリンク