Ground Penetrating Radar | St. Lawrence University Geology

Ground Penetrating Radar

 Ground Penetrating Radar or GPR is a non-invasive remote-sensing technique, which is a tool used to help answer a variety of problems. In geology, our Pulse EKKO 100 GPR unit has been used for: a) geologic mapping of rock, sediment and soil units, b) “viewing” buried channels, c) geomorphology, d) flood-plain analysis, e) caves and karst studies and others. Our GPR is also used to support geoarchaeological field problems such as “viewing” structure inside aboriginal sites.

A recent work completed by alumnus Christopher Stevens ’07 (Stevens and Robinson, 2007) highlights one facet of our GPR’s flexibility. Across the St. Lawrence region are a series of relict or ancient lake deltas (Figure 1). These deltas are important clues to marking the limit of an ancient ice-age lake that covered the area 1,000’s of years ago. Our Pulse EKKO 1000 GPR unit was used to image or “see” the subsurface makeup of these delta units—without digging!  By remotely viewing and interpreting the internal structure of these deltas, Christopher was able to determine two phases of this ice-age lake. All in all, a better understanding of this ancient lake and how it changed size helps us understand the activity of the large ice sheet that created it.

Reference: Stevens, C.W. and Robinson, S.D., 2007, The internal structure of relict lacustrine deltas, northern New York, in Baker, G.S. and Jol, H.M., eds., Stratigraphic analyses using GPR: Geological Society of America Special Paper #432, pp 93-101.