DRONE TECHNOLOGY, STRUCTURE FROM MOTION, AND LIME VISUALIZATION SOFTWARE TO MAP SEDIMENTARY EXPOSURES IN THE NEWARK BASIN

Drone technology has expanded in use for both private and public sectors, especially within the geosciences. With the unique nature of geosciences often involving field work as a necessary component for education and research, the use of drones has been able to aid in both of these areas. Imagery collected from drones offers a high resolution view, comparable, if not better than the orthoimagery currently available (i.e., LIDAR). Structure from Motion photogrammetry programs, such as Agisoft Metashape, Pix4D, etc., convert 2D images to 3D models, and can be used to recreate scaled and georeferenced 3D models of areas of interest. Paired with geologic interpretation programs, such as the LIME 3D Visualization and Interpretation software, further temporal and spatial correlations can be made beyond what can normally be done through typical geologic observation. This project focuses on applying these methods to further understand the extent and accuracy of mapping small and large scale geologic features at the outcrop level at a rift basin alluvial fan.

A road cut in Milford, NJ, known as “Pebble Bluff”, was selected for this study because it is a well documented portion of the Passaic Formation that shows alternation of alluvium and lacustrine deposits (Olsen et al., 1986). The goal of this study was to reconcile both small (hand sample size) and large (outcrop, aerial view) scale features in the generated 3D model. Given its location in the Newark Basin, this exposure is ideal for both mapping and testing the abilities of Structure from Motion for documentation. Initial results show medium scale features, such as bedding planes, to be well imaged and traceable along the entirety of the road cut. More detailed images taken at smaller scales, mostly documenting the presence of caliche, had to be manually aligned within the model.

Future work will utilize LIME to further trace and correlate rock units to other outcrops in the region. The 3D data developed in this study will be able to act as an instructional and mapping aid for both formal and informal education groups that use Pebble Bluff. This technology and instrumentation will provide further support in the understanding of fundamental geologic concepts, offering a new mechanism for observation and interpretation.