Characterization of the Blue Mountain Geothermal Field Using Anisotropic Elastic-Waveform Inversion

Session: Full-Waveform Inversion: Recent Advances and Applications [Poster]
Type: Poster
Date: 4/29/2020
Time: 08:00 AM
Room: Ballroom
Description: 

Subsurface characterization is an essential yet challenging component in geothermal exploration. Faults and fractures in geothermal fields usually lead to highly complex geological structures that are difficult to characterize using conventional or simplified seismic methods. Full-waveform inversion is a powerful tool for subsurface medium property characterization by minimizing the misfit between observed and synthetic seismic waveforms. We develop a comprehensive workflow that incorporates anisotropic traveltime tomography, anisotropic elastic-waveform inversion, anisotropic elastic reverse-time migration and fault detection methods to accurately characterize the geology at the Blue Mountain geothermal field located about 35 km west of the town Winnemucca in northern Nevada. We first use anisotropic traveltime tomography and refraction anisotropic elastic-waveform inversion to derive the near-surface elastic medium properties, including P- and S-wave velocities and anisotropic parameters, of the Blue Mountain geothermal field. We then invert for the velocity and anisotropic parameter models of the deeper region using reflection anisotropic elastic-waveform inversion. We finally obtain a high-resolution subsurface structural image using anisotropic elastic reverse-time migration, and detect faults at the Blue Mountain geothermal field using a state-of-the-art fault detection method. Our workflow reveals high-resolution subsurface geological structures, particularly several major and minor faults in the Blue Mountain geothermal field. The results can provide valuable information for geothermal well placement at the Blue Mountain geothermal field.

Presenting Author: Kai Gao

Authors