High-Resolution Seismic Methods for Geothermal Exploration and Monitoring across the Hengill volcanic area

Abstract

Hengill volcano and its associated geothermal fields represent Iceland's most productive harnessed high-temperature geothermal fields, where energy is provided by cooling magmatic intrusions connected to three volcanic systems. The crustal structure in this area is highly heterogeneous and shaped by the intricate interplay between tectonic forces and magmatic/hydrothermal activities, making detailed subsurface characterization challenging. In the Northern part of the Hengill geothermal field, super-hot geothermal resources have been spotted that are currently considered for geothermal exploration. Over the past years, we have studied the site in great detail, and acquired high-quality datasets from a 40+broadband seismic station array, a dense 500+ station nodal array and distributed acoustic sensing data from a fibre line crossing the area. We compare the results that we obtained from various seismic imaging methods e.g., earthquake tomography, ambient noise methods and discuss their potential and limitation to enable high-resolution seismic methods for exploration and monitoring of geothermal plays in such complex volcanic environments.