Geophysics seminar: Shunguo Wang (IGPP) "Imaging Fracture Zones in Shallow Subsurface Using Resistivity-based Geophysical Methods"

06/01/2018 - 3:30pm to 4:30pm
Munk Conference Room
Event Description: 
Talk abstract: 

Geophysical methods are non-invasive and allow an effective way of understanding subsurface structures and their physical properties. One of the main challenges in this is the non-uniqueness of the geophysical models and that several different models can explain a dataset to an agreeable fit. Moreover, noise and limitations in resolution, which are inherent to field data, are additional obstacles for obtaining a true physical model of the subsurface. Facing all these challenges, radio-magnetotelluric (RMT), boat-towed RMT, boat-towed controlled source MT (CSMT), electrical resistivity tomography (ERT) are jointly used for fracture zone delineation under shallow water-bodies. The joint approach, as compared with any individual method, shows a better ability to both resolve the geological targets and to assist in understanding the subsurface geology that hosts these targets. For examples: by performing the joint inversion of lake-floor ERT and boat-towed RMT data, a fracture zone is better delineated with greater details compared with single inversions; by employing boat-towed CSMT measurements and jointly inverting with boat-towed RMT data, the subsurface structures are better resolved than by inverting each dataset alone. The studies are useful for near-surface applications including, for examples, engineering purposes such as planning of underground infrastructures, site characterization in connection with energy or waste storage, and geohazard investigations.

For more information on this event, contact: 
Michael Murphy
Event Calendar: