Alluvial Sands 2D GPR & ERI

Integrating GPR and ERI to Map Alluvial Sand and Gravel Variations to 6 m Depth

GPR (100 MHz) and ERI profiles of alluvial gravelly sand in Nottinghamshire UK. Both near-surface zones of high resistiviity (orange-red) coincide with dipping reflection events in the GPR record. This combination is strong evidence for gravelly sand in paleochannels, as confirmed by coring. Coincidence of arching reflection events in center of GPR profile with complex moderate resistivity confirm an interchannel sand bar.  Low resistivities (blues) under the gravelly sand are confirmed bedrock (Mercia Mudstone).*

* Tye, A. M., Kessler, H., Ambrose, K., Williams, J. D. O., D. Tragheim, A. Scheib, Raines, M., and Kuras, O., 2011, Using integrated near-surface geophysical surveys to aid mapping and interpretation of geology in an alluvial landscape within a 3D soil-geology framework: Near Surface Geophysics, v. 9, no. 1, p. 15-31.