The Role of a Stress Model in Stimulation Planning at the Newberry Volcano EGS Demonstration Project

Abstract

Field work and planning has begun on the Enhanced Geothermal Systems (EGS) Demonstration Project at Newberry Volcano in central Oregon. The tectonic and volcanic setting of the site suggests that the stress state and fracture patterns may be complex. Because the stress state is a primary control on the growth of an EGS reservoir, the technical team has begun building a preliminary 3-D stress model for Newberry by collecting new field and laboratory data, including borehole imaging using an ultrasonic borehole televiewer, micro-seismic monitoring through a local network, mineralogical characterization and mechanical testing of existing core, and regional fault and fracture mapping using LiDAR. Analysis of the data sets has just begun, but preliminary results indicate that the stress and fracture patterns may be more straightforward than indicated by the complex geologic setting.