Using Ground based LiDAR to identify the processes of bluff erosion in the LeSueur River basin in Southern MinnesotaAmerican Geophysical Union, Fall Meeting 2009 (2009)
AbstractLike with aerial LiDAR, the many benefits of ground ground-based LiDAR are continuing to be discovered. Ground Ground-based LiDAR offers high high-resolution surveys of vertical features like bluffs and stream banks. When the surveys are repeated and compared, the data can reveal not only the rate of erosion, but in some cases the processes responsible for erosion. Three years of LiDAR surveys at fifteen sites in the Le Sueur River basin in southern Minnesota have revealed that the bluff composition as well as the degree of consolidation dictates the erosion rate and the processes which cause them to erode. The bluffs in this basin are composed of glacial tills at varying degrees of compaction. Because this basin is incising, many of the bluffs are cut into terraces capped by alluvium. Over-consolidated bluffs tend to fail along joints, as large blocks. The tills which are not over-consolidated fail due to undercutting as the toe of the bluff is eroded by the river. Finally, those bluffs which are capped by alluvium fail do due to undercutting at the toe, as well as by groundwater flow through the gravel layer at the base of the alluvium. Bluffs in the Le Sueur River contribute significantly towards a turbidity impairment in the basin, and understanding both the rate of erosion and the processes by which these bluffs erode can help managers target remediation practices. In this basin ground-based LiDAR has not only helped to quantify bluff erosion, but has also shown the dominant erosion process.
Citation InformationPatrick Belmont, S S Day, K B Gran, C E Jennings, et al.. "Using Ground based LiDAR to identify the processes of bluff erosion in the LeSueur River basin in Southern Minnesota" American Geophysical Union, Fall Meeting 2009 (2009)
Available at: http://works.bepress.com/patrick_belmont/86/