A010 GEOELECTRIC SURVEYS TO SUPPLEMENT TO DETERMINE THE STRUCTURE OF HYDRO- THERMAL SYSTEMS – CASE STUDY VULCANO Abstract 1 Geophysical methods provide the tools to investigate 3D volcanic structures and corresponding hhdrothermal systems. Even though seismic and gravimetric data have proven to supply valuable information the application of additional potential field methods is of great benefit for improving this picture. Geoelectric multi-electrode tomographic sections give a detailed image of the subsurface resistivity distribution. The Geological Survey of Austria (GBA) has a huge expertise in this field applied to volcanic areas. From 1996 to 2004 the GBA has conducted dozens of