岡山県川上町における成羽層群とそれを覆う石灰岩体の構造関係

その他

Structural relationship between the Triassic Nariwa Group and overlying Permian limestone blocks which have been believed to be portions of a nappe body，has been studied in Kawakami，central Okayama，Japan．Based on detail field mapping and observation in some large exposures，spatial distribution of these rocks and relations among them were obtained．The limestone blocks are concluded to be reworked deposits formed as basal conglomerate of the Cretaceaus Kanmon Group．Because，greenish volcanic rocks of the Cretaceous Kanmon Group seems to be lower than the limestone body stratigraphically as a whole．And both of them cover sandstone and shale beds of the Triassic Nariwa Group．Considering that there are many landslides in this area，low angle faults of the nappe structure are understoodto be such landslide planes formed just below the ground surface．