courtesy of NASA/JPL |
Safsaf Oasis, Egypt
The radar image of south central Egypt demonstrates SIR-C/X-SAR’s
unique capability to penetrate thin sand cover in arid regions and reveal details hidden
below the surface. Nearly all the structures seen in this image are invisible to the naked
eye and to conventional optical satellite sensors. Features appear in various colors
because the three separate radar wavelengths are able to penetrate the sand to different
depths. Areas that appear red or orange are places that can be seen only by the longest
wavelength (L-band), and they are the deepest of the buried structures.
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| Field studies in this are indicate that L-band
can penetrate as much as 2 meters (6.5 feet) of very dry sand to image buried rock
structures. Ancient drainage channels at the bottom of the image are filled with sand more
than 2 meters thick, and appear dark because the radar waves cannot penetrate them. The
fractured orange areas at the top of the image and the blue circular structures in the
center of the image are granitic areas that may contain mineral ore deposits. Scientists
are using the penetrating capabilties of radar imaging in desert areas for work in
archaeology and structural geology, for mineral exploration and searches for water
resources, and for studies of ancient climates |
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