Survey of Methods, Challenges, and Pathways Forward for Superhot Rock Characterization

Abstract

There is a growing governmental, commercial, and academic interest in high enthalpy, Superhot Rock (SHR) geothermal systems due to their high energy density and thus the potential for large-scale, economic electricity production. However, the highly site-specific aspects of geothermal power production introduce risks that can be a major obstacle to resource development. Geophysical methods must be optimized and adapted for SHR resource characterization to reduce exploration risk and improve reservoir monitoring techniques. Field-validation and laboratory facilities to measure geophysical properties at these conditions are limited, so it's important to best leverage the available information and target further data collection. This study examines the capabilities and limitations of geophysical methods that target subsurface features, identifies gaps in these methods for SHR characterization, and suggests strategies to close these gaps. We explore a range of geophysical-based methods that target key subsurface properties - temperature, stress state, structures and permeability - that are crucial to characterizing SHR resources.