3:00 PM - 3:15 PM
[SGL37-04] Relationship between trends in Miocene basin development and outcrop-based depositional cycles and geological structures
Keywords:Miocene, back arc, Northeast Japan, sedimentary facies, fault
This outcrop-based study discusses basin development in Northeast Japan by sedimentary facies and structural analysis, considering cyclicity and basin geometry of the Mikawa and Tsugawa basins in the Tsugawa-Aizu province. The study area, the Tsugawa area in Aga, Niigata, has various scale basins which include the Mikawa basin in the west and the Tsugawa basin in the east. We estimate vertical changes of depositional environments by field work on Miocene deposits from the Tsugawa Formation to the Nomura Formation in the Yagiyama area, eastern part of the Tsugawa basin.
Comparison between the Mikawa basin and the Tsugawa basin show that the cyclicity of these basins is similar to each other. This study considers basin development also from fault trends by fault analysis. In general, geological structures in the Mikawa area show NNW-SSE to N-S trends, while those in the Yagiyama area have an obvious NW-SE trend.