Transition of the sedimentation system of the alluvium and formation of the plain by the large-scale event sedimentation

最初的屏障一般形成于约8000年前的新泻平原的冲积层。在阿加诺河流域，三角洲系统的进展已经得到证实。在福岛县的忠见川中产阶级地区的沼泽火山，大约4700年前发生了火山碎屑流喷发。火山碎屑流暂时停止了忠见河。大坝倒塌造成的大规模洪水超过约100公里，流经多见河和阿加诺河。这次洪水在平原上带来的巨大火山碎屑迅速推进三角洲系统平原的阿加诺河流域。整个屏障纵队就这样前进。

Initial barrier was generally formed the alluvium in the Niigata plain about 8000 ago. It has been proven that the delta system advances in the Agano River watershed. In Numazawa volcano in the Tadami River middle class area in Fukushima Prefecture, there was the pyroclastic flow eruption about 4700 ago. The pyroclastic flow temporarily stopped Tadami River. The large-scale floodflow by a collapse of the dam over about 100km flowed Tadami River and Agano River. The enormous pyroclast which this flood brought about in the plain rapidly advanced of the Agano River watershed of the plain of the delta system. The whole barrier column advanced by this.