Subsurface imaging and mapping of karst features were completed in Texas using geophysical methods to assess potential geohazards to key infrastructure and related construction. Karst features are prevalent in the central and west Texas regions and are found predominantly in the Edwards Group and other similar limestone formations in the area. The Edwards is also a major aquifer in the central Texas region and much of the deeper karst features are water filled. Depending on the location and depth, these features can be filled with air, sediment, water, or a combination thereof and will provide different physical responses to geophysical measurements. These karst features can be a concern in the region due to their potential adverse effect on pre and post construction activities. Additionally, some karst features in the Texas area are home to various endangered species and provide an important component of their habitat. Subsurface imaging using geophysical methods such as electrical resistivity tomography (ERT) and seismic refraction tomography (SRT) can be useful in mapping these features to help address potential geohazards to engineering and construction related concerns. Case histories are presented to support the use of geophysical methods for characterization and mapping of karst features.
Primary Author / Conference Presenter:
Collier Geophysics, LLC
Round Rock, Texas, USA