Measuring thaw depth beneath peat-lined arctic streams using ground-penetrating radar

• Main Authors: John H Bradford, James P Mcnamara, William Bowden, Michael N Gooseff
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2005
• Subjects: Arctic; permafrost
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.1075.5319; http://icewater.boisestate.edu/boisefront-products/other/Publications/mcnamaraother/bradford05.pdf

Abstract: In arctic streams, depth of thaw beneath the stream channel is likely a significant parameter controlling hyporheic zone hydrology and biogeochemical cycling. As part of an interdisciplinary study of this system, we conducted a field investigation to test the effectiveness of imaging substream permafrost using ground-penetrating radar (GPR). We investigated three sites characterized by low-energy water flow, organic material lining the streambeds, and water depths ranging from 0Ð2 to 2 m. We acquired data using a 200 MHz pulsed radar system with the antennas mounted in the bottom of a small rubber boat that was pulled across the stream while triggering the radar at a constant rate. We achieved excellent results at all three sites, with a clear continuous image of the permafrost boundary both peripheral to and beneath the stream. Our results demonstrate that GPR can be an effective tool for measuring substream thaw depth.