9:30 AM - 9:45 AM
[HGM22-03] Experimental study of the effect of partial uplift on river channels
Keywords:river channel, uplift, laboratory experiments
Flume experiments were conducted to examine the effects of uplift on river channels in which the uplift area was restricted to the middle reaches. Experimental landform was evolved by exerting fine water mist on the slope consisting of a mixture of fine sand and clay, and the uplift was realized by jacking up the partial area of the flume bottom. The conventional idea that the occurrence of water gaps was determined by the balance between rates of uplift and downward erosion is true locally. The rate of down erosion is, however, variable due to the change of channel paths in the meso-scale. The avoidance of flowing in the uplift area tends to cause a new confluence and higher stream power producing larger erosion rate. A confluence makes the possibility of forming water gap high. The avoidance of the uplift area, however, does not always induce a confluence, in which the water gap is not generated.