Abstract:
An aerogeophysical survey of the western Marie Byrd Land region of
Antarctica was flown in Dec. 1998-Jan. 1999, measuring surface and
base of ice elevation by radar and strength of magnetic and gravity
fields. The coverage area measured about 460 by 360 km, long
dimension oriented NE, and included the Shirase Coast of the eastern
Ross
... Ice Shelf, much of the Edward VII Peninsula, the Sulzberger Ice
Shelf, and the Ford Ranges. Track spacing was either 5.3 or 10.6 km
over most of the area. The 60 Mhz radar system usually provided good
images of the base of the ice for thicknesses less than 1 km but
rarely imaged thicknesses greater than 1.5 km. Determination of
gravity anomalies required corrections for acceleration of the
aircraft as measured by differential carrier-phase GPS navigation,
filtering to remove wavelengths less than 10 km, which are commonly
contaminated by aircraft motion, and editing of occasional spikes.
The gravity anomalies allow estimation of bed topography under
floating ice and under ice too thick for radar imaging. Magnetic
anomaly reduction includes a correction for daily variation as
measured at the base camp. Data formats for all observations include
files for original flight profiles and grids of edited data at 1.06 km
node spacing. 
