High Resolution Monitoring of the Evolution of a Rapidly Eroding Bedrock Gorge in Western Taiwan
The Da'an River gorge in western Taiwan is the result of uplift of the riverbed during an earthquake in 1999. The river is now rapidly incising into this zone of uplift and has carved a dramatic bedrock gorge 1200 m long and up to 20 m deep. The extremely rapid pace of incision provides an ideal opportunity to study the interactions between uplift, discharge, sediment supply, channel width, and knickpoint propagation.
Since 2009, Kristen Cook has used repeat terrestrial laser scans, UAV surveys, real-time kinematic GPS surveys, and aerial photographs to quantify changes in the gorge with high spatial and temporal resolution (high resolution topographic surveys). By quantifying changes on the event scale, we can explore the relationship between flood magnitude and impact, as well as the controls on lateral erosion and gorge widening. Time-lapse cameras and seismic monitoring also provide information about intra-flood bed erosion and deposition.