DETECTING GEOMORPHOLOGIC CHANGES - APPLYING INNOVATIONS TO SPATIAL DATA GATHERING

Structure from Motion (SfM) Photogrammetry is an emerging, viable technology to capture spatial data, being ever improved by innovations from researchers in computer science, geomorphology, archaeology, geography and other fields. It allows the extraction of point clouds from digital photographs using free or commercial software. This technology potentially provides great utility for mapping geomorphic features undergoing rapid change, such as streambanks regularly subject to fluvial erosion processes. To evaluate the potential of SfM for quickly mapping rapidly changing geomorphic features on short-time scales, it is tested on an eroding streambank on the Suncook River in Epsom, NH. Collected datasets show that precision varies based on the survey scope, level of detail, and the processing workflow used. The preliminary processing of two collected datasets shows how rapid repeat surveys can gather upwards of a quarter million points per half hour of field work. Given that traditional methods of measuring temporal geomorphic change at a single site are time-intensive data sets to produce, these results suggest the potential of SfM photogrammetry for use in fluvial and geologic hazards mapping, where capturing rapid physical changes is required.