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Fraser
2005-Aug-05, 03:50 PM
SUMMARY: The MARSIS radar instrument on board Mars Express is now extended and fully operational, and ESA scientists have begun using it to probe beneath the surface of Mars in search of water and ice. During this initial commissioning phase, operators have used the instrument to examine Mars' topography to compare its reading against previous readings of the Red Planet to make sure its calibrated correctly. Within a few weeks they'll start isolating areas where the radar is penetrating beneath the surface to start mapping out underground layers.

View full article (http://www.universetoday.com/am/publish/marsis_collects_1st_surface_data.html)

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cran
2005-Aug-07, 03:54 AM
It's a great start to what will be a major global subsurface survey. As a general rule for GPR (ground penetrating radar): the lower the frequency, the greater the depth penetration, but the lower the resolution of the signal.
Subsurface water will be highly 'reflective', and should therefore be rather easy to find...if MARSIS does find a water table...it's party time! :D
Distinguishing between successive sedimentary layers is a bit harder, but if the resolution is fine enough, and successive sedimentary layers are discerned....it's party time! :D
If there is not a near surface water table, or distinctive sedimentary basins, then the clearest distinction is likely to be between the loose cover and the first igneous rock layer.
High resolution tomography - particularly of the deep layers (crust/mantle; mantle/core) might still have to wait for surface 'hammer' seismics.