DEVELOPMENT AND MORPHOMETRIC ANALYSIS OF HIGH-RESOLUTION PHOTOGRAMMETRIC DIGITAL ELEVATION MODELS OF THE SOUTHEASTERN PARASITIC CONES OF BARVA VOLCANO

Barva volcano is one of several volcano complexes of the Cordillera Central massif that looms over the population, industry, and agricultural centers of Costa Rica’s Central Valley. In contrast to its more recently erupting neighboring volcano complexes, Barva has seldom received extensive investigations into its morphology and eruptive history, at least in part due to its period of recent inactivity and the extensive vegetation on its slopes that impedes ground surveying fieldwork. Therefore, remote sensing approaches must be employed to study Barva’s morphology effectively. This study contributes to a better understanding of Barva through our collection and analysis of high-resolution elevation data of six parasitic cones on Barva’s southeastern flank that have been assessed to align with Barva’s summit cones via a potential volcano-tectonic feature. An unmanned aerial vehicle (UAV) was deployed at each of the six parasitic cones to collect aerial imagery. These data were subsequently processed into digital elevation models (DEMs) and orthomosaics using the Structure-from-Motion program Agisoft Metashape. Surface measurements taken by a Real-time Kinematics (RTK) unit were used to provide accurate georeferencing for the models. As a result, this study provides high-resolution DEMs for all six parasitic cones of Barva’s southeastern flank from which morphometrics such as height, width, and slope angle were determined. Current efforts include applying an AI algorithm to identify vegetation on the orthomosaics so that the height of trees and shrubs can be removed from the DEMs. These models inform our perspective on how these parasitic cones might have developed. These cones pose a significant risk considering their location and arrangement within populated areas. Consequently, comprehensive hazard assessments at Barva are critically important to local communities. A better understanding of the development of the parasitic cones could contribute significantly to this end.