Study on investigation techniques of uplift rate using sediment of incised meander scars

Yasue, Kenichi; Tanikawa, Shinichi; Ninomiya, Atsushi*; Tanase, Atsushi*

We focused on the incised meander scars to be distributed along the river and carried out a study of the estimate technique of the uplift rate using the sediment on the scars. The incised meander scars more than 800 were extracted in Japanese Islands by interpretation of 1:25000 topographical maps. The scars are distributed over various altitudes. As a case study, we studied about uplift using the incised meander scars in an area along Totsukawa River where a typical the scars was distributed over various altitude. The sediment was got by machine digging of the high quality. Sedimentation age was estimated by volcanic ashes analysis. The age of the sediment on the incised meander scars of relative height approximately 90m from the present riverbed is approximately 300-400 thousand years ago. From these results, the uplift rate is estimated at a few ten centimeters for 1,000 years.