2024 Volume 133 Issue 3 Pages 195-218
The Hida belt in central Japan represents a unique geotectonic unit of non-subduction-related origin, in sharp contrast with the rest of the Phanerozoic crust in Japan. Its origin and relative geotectonic position with respect to surrounding continental blocks in East Asia, such as Greater South China (GSC), North China, and Siberia, remain unresolved. To confirm the geologic/orogenic identity of the Hida belt, the geochronology of detrital zircons is analyzed for seven non-marine sandstones of the Lower Cretaceous Tetori Group. New age data confirmed that all analyzed sandstones probably belong to Lower Cretaceous (Barremian to Aptian), regardless of areas within the belt. The trace element composition of detrital zircons indicates their derivation mostly from I-type granitoids, and in part from A-type granite. Late Triassic granitoids are extremely rare in the present Hida belt, and A-type granite is absent; nonetheless, the present data, together with large boulders in conglomerate, indicate extensive exposure of such granitoids in the Early Cretaceous provenance of the Tetori sedimentary basin. It is noteworthy that Late Triassic A-type granites occur solely in NE China within Far East Asia; thus an intimate link between the Hida belt and the Laoelin–Grodekov (LG) belt in the Russia/China/N. Korea border domain is suggested. As Tetori sandstones have a remarkable contrast in zircon age spectra with the coeval sandstones deposited in shallow marine fore-arc basins in Japan, the Tetori Group was deposited probably in the periphery of a large-scale inland non-marine basin in Cretaceous NE Asia, which was located particularly at the back-arc side of the active volcanic arc.
