High-resolution seismic-reflection characterization at a challenging Atlantic Coastal Plain groundwater flow site

High-resolution, shallow seismic reflection is consistently proven to be a powerful tool for imaging properties influencing groundwater flow. One of the most challenging aspects of any seismic reflection survey is defining the velocity field accurately and at high fidelity. When an accurate and densely populated velocity function can be defined and more complete migration techniques used, vadose to saturated transition zones and high velocity gradient problems can be overcome. Key to this feasibility study was the ability of the method to characterize key Atlantic Coastal Plain strata within the transition zone between vadose and saturated sediments in the upper 200 ft where groundwater movement influences transport and fate. These data possessed bed resolution potential on the order of 5 to 10 ft and spatial resolution better than 50 ft, clearly a requirement that demanded state-of-the-art application of the method.