Charting the Secret World of the Ocean Floor. The GEBCO Project 1903-2003 1 Interpolation and Contouring of Sparse Sounding Data By Hans Werner Schenke Alfred Wegener Institute for Polar and Marine Research Columbusstrasse D-27568 Bremerhaven Germany email: schenke@AWI-Bremerhaven.de Executive Summary The back of the moon and the surfaces of most planets of our solar system are better mapped than