Relics of the Panthalassa Ocean occur today in accretionary complexes and terranes on the entire Circum‐Pacific region. Among them, remains of shallow‐water carbonate systems provide valuable information about the ecology and environmental conditions that prevailed in this immense ocean. In this regard, the Shiriya Cape of the North Kitakami Belt (Aomori Prefecture, Honshu Island, Japan) is an essential place to study. Charact...

The Precambrian and lower Paleozoic units of the Japanese basement such as the Hida Oki and South Kitakami terranes have geological affinities with the eastern Asia continent and particularly strong correlation with units of the South China block. There are also indications from units such as the Hitachi metamorphics of the Abukuma terrane and blocks in the Maizuru terrane that some material may have been derived from the Nort...

Identifying and examining geological processes that have occurred in sediment‐starved trenches of ancient non‐accretionary subduction zones exposed on land are still challenging, because such style of subduction is believed to leave scarce rock records. Our new geological mapping, petrography of coarse clastic rocks, radiolarian and zircon U–Pb dating of the Shiriya accretionary complex in Northeast Japan suggest that the youn...

An accretionary complex, which contains fragments of a remnant island arc, was newly recognized in the Cretaceous accretionary terranes in Hokkaido, Japan. It consists of volcanics, volcanic conglomerate, intermediate to ultramafic intrusive rocks with island‐arc affinity including boninitic rocks, accompanied by chert and deformed terrigenous turbidites. Compared with the results of modern oceanic surveys, the preserved seque...

The Cretaceous accretionary complexes of the Idonnappu Zone in the Urakawa area are divided into five lithological units, four of which contain greenstone bodies. The Lower Cretaceous Naizawa Complex consists of two lithologic units. The Basaltic Unit (B‐Unit) is a large‐scale tectonic slab of greenstone, consisting of depleted tholeiite similar to that of the Lower Sorachi Ophiolite (basal forearc basin ophiolite) in the Sora...