Potentialities of ultrawideband GPR in low-resistivity geoenvironments

We assess the potentia4lities of ultrawideband (UWB) electromagnetic pulse sounding of low-resistivity geoenvironments using the ground-penetrating radar (GPR) system developed by us and compare the obtained results with 2D electrical resistivity tomography and standard GPR data. The research was performed in an area of Quaternary clay deposits with a resistivity of 20-50 Ohmm. For an OKO-2 GPR antenna with a center frequency of 150 MHz, the sounding depth is 2-4 m, whereas UWB sounding provides penetration of the GPR pulse to a depth of 30-40 m. Deep UWB sounding of low-resistivity environments is possible under the following conditions: use of generators based on drift step recovery diodes (DSRDs), high matching of the UWB receiving and transmitting antennas to the environment, and an increase in the noise immunity of the recording system, in particular, due to a decrease in the intensity of air waves.