Magnetic Field Imaging of Salt Structures at Nordkapp Basin, Barents Sea

We show that high-resolution aeromagnetic surveys, although rarely employed in the research of salt structures, may be an effective and low-cost tool for mapping diapirism. A multiscale analysis of a high-resolution magnetic data set at Nordkapp Basin in the Barents Sea, allows a clear reconstruction of the main salt diapirs of the basin using Multiridge and Compact Depth from Extreme Points methods. We provide a 3-D model of the diapirs extended from 500 to 4,000 m below sea level, characterized by a general low magnetization contrast no larger than −0.08 A/m. The 3-D model is consistent with the salt top depth estimated by 2-D seismics, with borehole data and with the 2-D gravity model of the Uranus diapir. Our imaging shows the capability of the magnetic method that gives new and comprehensive pictures of salt diapirism.