"제주도 암반 하천의 분합류 패턴과 유로 분기 - 색달·중문천을 사례로 -"

Abstract

Anastomosing channels unusually occur in the middle reach of the Saekdal-Jungmun River in southern Jeju Island, Korea. This study has examined the characteristics of channel bifurcation, which produces an anastomosing pattern in the bedrock river system. The pattern has proved to be composed of approximately forty channel reaches that are connected to each other through fifteen bifurcations and sixteen confluences. The channel formation by flow diversion from an existing channel onto an adjacent interfluve could be largely caused by four factors: an abrupt channel narrowing and widening, a micro-topography on a rocky river-bed, and an abrupt change in flow direction. Splitting channels have generally shown an acute bifurcation angle. By contrast, the bifurcations, which are caused by abrupt channel narrowing and changes in flow direction, could generate an obtuse angle.