Detrital zircon geochronology of the Silurian-Lower Cretaceous continuous succession of the South Kitakami Belt, Northeast Japan

U-Pb analyses of more than 1,000 single detrital zircons from 16 formations of the Silurian-Lower Cretaceous continuous succession of the South Kitakami Belt (SKB), Northeast Japan, provide a detrital zircon reference for the complex continental-margin orogen of Japan. As a result, three tectonic phases were discriminated. Siluro-Devonian sandstone samples contain many syn-sedimentary zircons and 36.5-48.0% of Precambrian zircons scattering between 700 Ma and 3,000 Ma, suggesting that they were deposited along an active continental margin of East Gondwana. Permian-Early Jurassic sandstone samples contain virtually no Precambrian zircons, suggesting that they were deposited along the active margin of an oceanic island arc. Middle Jurassic-Early Cretaceous sandstone samples contain many 300-170 Ma zircons and up to 28% of Paleoproterozoic (around 1,850 Ma) zircons but no Neoproterozoic zircons. Moreover, the zircons during the magmatic hiatus in Korea (158-110 Ma) were detected only in one Lower Cretaceous sandstone sample. The age distribution suggests that the Paleoproterozoic zircons in the Middle Jurassic-Lower Cretaceous sandstone of the SKB were most likely supplied from a Paleoproterozoic orogen in the North China Block. Thus, the South Kitakami Paleoland, which accumulated the continuous succession of the SKB was born along a margin of Gondwana in the Silurian-Devonian, rifted from the continent and drifted in the Tethys ocean as an oceanic island arc in the Permian-Early Jurassic, and finally amalgamated along an active continental margin where detrital zircons of the North China Block were supplied in the Middle Jurassic.