Regional and detailed geologic studies of northern Alaska and other parts of the Arctic are hampered by the high-cost of doing field work in this remote and generally inhospitable region. Satellite-based synthetic aperture radar (SAR) could provide a relatively inexpensive remote sensing alternative for regional geologic studies in arctic regions. SAR systems have the advantage of being able to `see' the Earth's surface regardless of cloud and light conditions. While SAR imagery has been utilized in geologic studies of tropical regions, its utility in arctic regions, where ground-cover is minimal, is still being tested.
The northeastern Brooks Range was chosen to test the usefulness of SAR in geologic studies in arctic regions because of the relatively large amount of ground data available from the area. ERS-1 data was terrain-corrected and compiled into a mosaic of the entire range. Preliminary analysis suggests that structural features and gross lithologic differences are readily discernible on individual images and the mosaic. Carbonate and clastic rocks involved in regional-scale folding give remarkably different radar response and can easily be distinguished on the imagery. Faults can be distinguished as linear features or juxtaposition of different rock types.
The effect of surface roughness and water content, and therefore lithology, can be further enhanced by removing the effect of the terrain on the radar response. The resulting image shows no topography but clearly highlights lithologic variations, providing an additional mapping tool.
Future studies aim at utilizing ERS-1 and 2, and RadarSat radar data, and ADEOS optical data in geologic studies of the central and western Brooks Range, northwestern Canada, and the Russian arctic.
Funded by industry sponsors of the Tectonics and Sedimentation Research
Group and by NASA.
Scientific personnel:
C. Hanks
and
R. Guritz
(ASF)