Interpretation of Airborne Gamma-ray Data of Socorro Island, Mexico

摘要

In February 2009, the Geological Survey of Austria performed an airborne geophysical survey on Socorro Island, applying magnetic, electromagnetic and radiometric measurements. Gamma-ray data has been processed with up-to-date radiometric processing software and interpreted with the focus on comparing it with geologic mapping results. Due to the remote position of the island, only few geologic maps were available. Very interesting results could be achieved from the comparison with a map of the island by E.A. Carballido-Sanchez and a map of the easily accessible Lomas Coloradas area by W.A. Bohrson and M.R. Reid. It was largely possible to confirm the studies of W.A. Bohrson and M.R. Reid. In contrast, the radiometric results in some parts disagree with the classification of E.A. Carballido-Sanchez. Main differences are three trachyte domes, a cinder cone and a large lava flow, which all have been assigned to the Lomas Coloradas basalts by E.A. Carballido- Sanchez and which could be interpreted as postcaldera silicic products by means of radiometric data. Interpreting radiometric data of Socorro was particularly interesting, as only few geophysical and geological results existed from the island.