Written by Keith Williams
14 January 2020
The Lake Agnes rock glacier dominates the Lake Agnes cirque, near Cameron Pass in northern Colorado, however, little is known about its kinematics or dynamics. To determine the motion of the rock glacier, UNAVCO supported Colorado State University researchers with two sets of tools that were used simultaneously: terrestrial laser scanning (TLS) and an uncrewed aircraft system (UAS). The UAS was used to take sets of overlapping photos to be used for structure from motion (SfM) photogrammetry. For this first survey, TLS was used as the primary instrument with UAS SfM filling in the gaps. These gaps are the result of surveying from a ground-based platform, which is unable to image over the undulations of, and down into, the deepest depressions of the rock glacier.
Using these two methods simultaneously also allowed for a comparison. Initial analysis indicates that the accuracy of the UAS SfM could be very similar to the accuracy of the TLS, with many additional benefits. These benefits include:
So, how fast is the rock glacier moving? We can't yet answer that question, as all we have is a very detailed model from a single, initial observation; later this year we will repeat this collection, which will allow a 3D calculation of velocities between the two datasets. Stay tuned!
Last modified: 2020-01-28 22:51:36 America/Denver