Japan Geoscience Union Meeting 2018

Presentation information

[JJ] Oral

H (Human Geosciences) » H-GM Geomorphology

[H-GM03] Geomorphology

Wed. May 23, 2018 10:45 AM - 12:15 PM 102 (1F International Conference Hall, Makuhari Messe)

convener:Tsuyoshi Hattanji(Faculty of Life and Environmental Sciences, University of Tsukuba), Masayuki Seto(Fukushima Future Center for Regional Revitalization, Fukushima University), Hiroshi Shimazu(立正大学地球環境科学部地理学科), Chairperson:Wakasa Sachi

11:00 AM - 11:15 AM

[HGM03-07] Relationship between channel migration processes and former micro landforms on the riverbed in Kamikochi region, the upper Azusa River, central Japan

*Hiroshi Shimazu1 (1.Department of Geography, Faculty of Geo-Environmental Science, Rissho University)

Keywords:braided channel, channel migration, micro landform, riverbed, Kamikochi, Azusa river

The purpose of this study is to discuss relationships between channel migration process and micro landforms on riverbed in Kamikochi region, the upper Azusa River, central Japan. Based on ground surveying geomorphological maps of the observation area which were made every year in summer season. Interval shooting cameras took photographs every 15 or 20 minutes interval between 2011 and 2016. Also section surveying performed every autumn season.
During the Bai-u rainy season in 2013 and 2017 the major channel migrations occurred. On that days daily rain fall were over 140 mm. Those heavy rain events caused the bankfull discharge and the major channel migration. When the channel migration occurred, without gradual lateral move of channels, former channels were buried and/or narrowed and new main channels excavated tracing small channels and/or small ditches which had existed just before channel migration.