Magnetic Investigations During the 16th and 17th Expeditions to the Bulgarian Antarctic Base at Livingston Island

Geophysical methods are an important part of the scientific investigations around the Bulgarian Antarctic Base “St Kliment Ohridski” at Livingston Island. Dykes, plutonic and metamorphic rocks are sources of intensive magnetic anomalies there. The field and laboratory analyses show strong contrasts in magnetic susceptibility of sedimentary rocks (median value of 10.5 SI/g) and dykes (median value of 924.6 SI/g). Remnant magnetizations of sedimentary rocks are in the range (85 – 170) x10-6 A/m. The magnetic field measurements in the severe Antarctic conditions and high latitudes need special experience so that reliable results to be acquired. An intensive magnetic anomaly over a dyke with variable depth and width we put under analysis and quantitative interpretation using the direct inverse methods of Euler and Werner deconvolutions. The results allow the dyke parameters, depth and width, to be estimated and glacier thickness and abrupt to be tracked along the observed magnetic anomaly.