| Title | Building Subsurface Velocity Models with Sharp Interfaces and Steeply-Dipping Fault Zones Using Elastic-Waveform Inversion with Edge-Guided Regularization |
|---|---|
| Authors | Youzuo LIN and Lianjie HUANG |
| Year | 2014 |
| Conference | Stanford Geothermal Workshop |
| Keywords | elastic-waveform inversion, elastic reverse-time migration, total-variation regularization, edge-guided regularization |
| Abstract | Elastic reverse-time migration of multi-component data has the potential to directly image steeply-dipping fault zones for geothermal exploration. However, this imaging method requires an accurate velocity model. Elastic-waveform inversion is a promising tool for velocity estimation. Because of the ill-posedness of elastic-waveform inversion, it is a great challenge to accurately obtain velocity estimation, particularly in the deep regions and fault zones. To improve velocity model building, we develop an elastic-waveform inversion method with an edge-guided modified total-variation regularization scheme to improve the inversion accuracy and robustness, particularly for sharp interfaces and steeply-dipping fault zones. The new regularization scheme incorporates the edge information into elastic-waveform inversion. The edge information of subsurface interfaces is obtained iteratively using migration imaging during elastic-waveform inversion. We validate the improved capability of our new elastic-waveform inversion method using synthetic seismic data for a Soda Lake geothermal model containing several steeply-dipping fault zones. The improved velocity model could significantly improve direct imaging of steeply-dipping fault zones. |