A Geothermal Exploration Strategy Using High Resolution Aeromagnetic Surveys for the Basin-and-Range Province

Abstract

Basin-and-range geothermal resources are typically fault-controlled, deep-circulation systems. They commonly occur beneath thick sequences of Tertiary and Quaternary basin-fill sediments which hinder understanding of fault geometries and faulting patterns. Recent experience at Dixie Valley and survey of the literature for other systems suggest a low-cost and rapid exploration strategy for establishing basin geometries, patterns of Quaternary faulting in and beneath basin-fill sediments, and rationale to select locations for other geophysical surveys and drilling. The strategy involves standard geologic and geophysical techniques but includes early deployment of high-resolution aeromagnetic surveys to establish intra-basin fault patterns. This provides reliable information to focus deployment of more detailed and expensive geophysical surveys, and to site exploration wells. In addition, high-resolution aeromagnetic surveys can provide previously unavailable insight into the structural setting of established geothermal fields.