Multi-frequency ground-penetrating radar method for revealing complex sedimentary facies

Abstract

We attempted to resolve deltaic facies in Taylor Valley, Antarctica by using pulses centered near 120, 300 and 880 MHz, the latter of which has not yet been tried in this setting. The 120 MHz profiles clearly defined gross material changes, while the 300 MHz profiles added significant resolution to the topset, foreset and bottomset beds. The additional, higher frequency provided only about 2.5 m penetration however, the 10-15 cm pulse length revealed and defined multiple, fine-scale features that were not observed with the lower frequencies. The dip of these features is, in some instances, opposite to that of larger features profiled with the lower frequencies. Profiling with 880 MHz not only confirmed the greater complexity of the sedimentary architecture, but also allowed more robust interpretation of depositional processes. Generally, we recommend pulses centered near 300-400 MHz for detailed sedimentary profiling to about 6m depth.