| Title | Building a High-Resolution Velocity Model with Full-Waveform Inversion: A Case Study for Soda Lake Geothermal Field |
|---|---|
| Authors | Kai GAO, Lianjie HUANG |
| Year | 2016 |
| Conference | Stanford Geothermal Workshop |
| Keywords | Full-waveform inversion, Soda Lake geothermal field, high-resolution velocity model |
| Abstract | Full-waveform inversion is becoming a powerful tool to build high-resolution subsurface velocity models. Previous studies reveal that the Soda Lake geothermal field, situated several miles north-west of Fallon in Nevada, contains a complex fault system and complex geological structures. Therefore, it is a great challenge to build a high-resolution velocity model for the Soda Lake geothermal field using conventional tools such as migration velocity analysis. We have recently developed a suite of novel full-waveform inversion methods for high-resolution velocity inversion in complex media. We apply one of our methods to surface seismic data acquired at the Soda Lake geothermal field to build a high-resolution velocity model. Our full-waveform inversion employs a wavefield-energy normalization preconditioning technique and a modified total-variation regularization scheme to accelerate the convergence rate of the inversion and improve the recovery of sharp interfaces. Our results show that this inversion method can recover more fine-scale velocity variations compared with those built using migration velocity analysis. The high-resolution velocity model obtained using full-waveform inversion could improve imaging of the complex fault system at the Soda Lake geothermal field. |