Post-Scan Georeferencing of LiDAR Data from a Geological Exposure using ArcGIS™ for Adjustment

2. Department of Earth and Environmental Sciences, University of Manchester, Manchester, United Kingdom

Abstract: With the commonality of LiDAR increasing in usage amongst a wide array of disciplines, questions will arise regarding how the data is to be used and with what software the data will be visualized, manipulated, and utilized. One question that arises is whether a georeferenced point cloud is required and if so, should direct georeferencing be performed during a LiDAR scan or completed post-scan. Georeferencing, in terms of LiDAR, is the process in which real-world coordinates are assigned to every point in the point cloud such that all data points are grounded where they would be on earth. LiDAR scans don’t need to be georeferenced; however, for many geological studies, it is particularly important, especially when other types of data are to be integrated. Overall, this can lead to improved geological interpretations. For geological outcrops, such as the cliff face exposed at Joggins, Nova Scotia, the need for georeferenced LiDAR scans is essential for research relating to the density of the fossilized forest for paleo-reconstruction studies, for reservoir heterogeneity, compartmentalization studies, fluvial channel body aspect ratios, or the erosion rate of the cliff face. To save time at the geological exposure, georeferencing is not performed directly by the LiDAR system, but rather the coordinates from three strategically placed control points were recorded for post-scan georeferencing. This paper will introduce a workflow detailing the steps to achieve a fully georeferenced point cloud by knowing the ground locations of three targets incorporated into the LiDAR scan using conventional software, in this case, ArcGIS™.