Depositional timing of the Tetori Group along the Kumano-gawa River, Toyama Prefecture

A tuffaceous bed was discovered from the Tetori Group upstream of the Kumano-gawa River in the southern part of Toyama City, Toyama Prefecture. As a result of U–Pb dating of the zircon grains from a rock sample of the tuffaceous bed, we obtained the youngest cluster (weighted mean 206Pb/238U) date of 121.33 ± 0.80 Ma (2σ). This date indicates the Early Cretaceous (Late Barremian to Early Aptian) and is interpreted as the depositional age of the Tetori Group along the Kumano-gawa River.