Clastic rocks in Triassic bedded chert of the Mino terrane, central Japan and the Samarka terrane, Sikhote-Alin, Russia

摘要

Clastic rocks rarely occur in Triassic bedded chert of the Mino terrane, central Japan and Samarka terrane, Sikhote-Alin, Russia, and are composed mainly of silt- to granule-sized fragments of basaltic (?) volcanic rocks, altered volcanic glass, chert, siliceous shale and radiolarian remains, with minor amounts of polycrystalline quartz, plagioclase, lutecite and glauconite (?). Conodont fossils are concentrated in some clastic rocks. Ages of the clastic rocks range from late Anisian to early Carnian on the basis of radiolarian and conodont fossils. The clastic materials were most probably derived from the basaltic volcanic edifices such as oceanic island/plateau and immature volcanic arc, and were transported by turbidity currents.