SEDIMENT THICKNESS ESTIMATES FROM AEROMAGNETIC DATA ON THE WESTERN WEDDELL

Thirty-six profiles from the USAC aerogeophysical survey were used to calculate depth to magnetic basement estimates, using wavenumber and space domain techniques in an automated fashion. A good agreement between the two methods was attained and results were then gridded between 60, 440W and 73, 62°5. Bathymetric values were subtracted at each grid point, obtaining in that way a regional estimate of the sediment layer. Contour maps show that the magnetic basement gradually gets deeper from the Antarctic Peninsula margin to the east with increasing slope, until a North-South band is reached where the estimated sediment layer is very thick (10 km) around meridian 54OW. Further to the east the basement steps upward with corresponding thinning of the sediment layer.