Coastal Consulting and Exploration srl, Bari, Italy

The Albano Lake is the deepest volcanic lake among the volcanoes located in the Italian peninsula. It belongs to the Colli Albani volcanic complex whose last largest eruptions are dated back to about ~30 Kyr, although minor events likely occurred during historical times at 7000 yr B.P. or earlier. After the end of the volcanic activity the Crater of Albano became a lake whose level changes are known since historical times. On November 2005, was performed the first very high resolution bathymetric survey of the Albano lake by means of a multibeam echo sounder, integrated with the GPS/RTK positioning technique A particular effort was devoted to produce a high resolution morphobathimetric map, which aims to provide a Digital Terrain Model of the lake floor for wide applications. The surveys did not revealed significant gas exhalative centres, which should indicate a current active gas release from the lake floor. Here we show the technical details of the bathymetric surveys, the very high resolution bathymetric map and the main morphological features of the Albano Lake bottom.

On November 3, 2002 a shallow submarine gas eruption occurred in an area of 2.3 km2 east of Panarea (Aeolian volcanic arc, Southern Thyrrenian Sea, Italy). The exhalative area, surrounded by the islets of Dattilo, Panarelli, Lisca Bianca, Bottaro and Lisca Nera, has been known since historical times for the hydrothermal activity related to the Panarea volcanic complex. Due to the exceptional characteristics of the phenomenon, different geological, geochemical, geophysical and studies were carried out in this still poorly known volcanic area. A particular effort was devoted to producing a high resolution bathymetric map that also aimed to estimate the amount and location of the active exhalative centers and their variations in space and time. Data were obtained by three RTK multibeam surveys performed between December 2002 and December 2003. Here we show and discuss the technical details of the bathymetric surveys, the bathymetric map at 0.5 m resolution, and the accurate location of the 606 main exhalative centres active during the 2002-2003 crisis. The bathymetric data and the maps show two prevailing principal NE-SW and NW-SE alignments that match the spatial distribution of the exhalation centres. The accurate positioning at submeter accuracy of the gas vents is useful in the monitoring activity and to study their temporal and spatial variability.