Relationship between mineralogical composition and radiocesium on bottom sediment at estuary of Odaka River

Abstract

Estuary of alluvial is specific area which has shelved land form gradient and current velocity is degraded by mixing freshwater and seawater. The radiocaesium from the Fukushima nuclear accident fallout is strongly sorbed on fine grain size particles. It is necessary for fine grain size particles to evaluate behavior at estuary. we measured salinity concentration and sampled bottom sediment. Bottom sediments were analyzed by XRD and TEM. The results showed salinity distribution and the sediments include black color sediments. It is confirmed halloysite, diatome, and bacteria by TEM. The area has higher radiocaesium concentration than upstream.