HR: 1340h
AN: H53C-1386 [Abstracts]
TI: Comparing the Effectiveness of Ground-Penetrating Radar in Imaging Siliciclastic And Mafic- Volcaniclastic Dune Sands
AU: * Wilkins, D E
EM: dwilkins@boisestate.edu
AF: Department of Geosciences
Boise State University, 1910 University Drive, Boise, ID 83725, United States
AU: Clement, W
EM: wclement@boisestate.edu
AF: Center for the Investigation of the Shallow Subsurface
Boise State University, 1910 University Drive, Boise, ID 83725, United States
AB:
Experiments using ground-penetrating radar (GPR) systems in two, different dune sediment environments allow
comparisons of the relative effectiveness of subsurface imaging and feature detection. One experiment was
carried out in the Coral Pink Sand Dunes (CPSD) in southern Utah, and a second in the Grand County Off Road
Vehicle area in Moses Lake (ML), Washington. Both experiments used a MALA GPR system with 500MHz
antenna and similar data sampling and acquisition parameters. The dunes at the CPSD site are comprised of
nearly pure, very well sorted quartz sands. These sharply contrast with dunes at the ML site which are comprised
of basalt-rich (up to 80%) sands. The ML site was selected as a terrestrial analog to Martian dunes that have
been shown in other studies to have a similar mineralogy. As with other quartz dune studies, radar images
gathered at the CPSD site clearly show cross-bedding structures and were able to identify the bedrock/dune
interface as well as the locally shallow water table. The imagery collected at the ML site was not as clear, but
some dune structures, ash beds, and water are visible in the imagery. We propose that thee higher basalt
content at the ML sites results in greater signal loss than in the siliciclastic sands at the CPSD site. The reduced
signal transmissivity in the mafic sands may have implications for selection of GPR instrumentation in future
Mars investigations.
DE: 1824 Geomorphology: general (1625)
DE: 9350 North America
SC: Hydrology [H]
MN: 2007 Fall Meeting