Geological map of Mount EtnaWest Rift (Italy)

Abstract

Mt Etna (3340 m a.s.l.) is the most active volcano in Europe, with more than 500 ka of geological history. In this work, a detailed structural and geological field survey of its West Rift was performed at 1:10,000 scale, by using lithostratigraphic criteria and unconformity-bounded units, in accordance with guidelines suggested by the International Stratigraphic Guide. In the studied area, lithostratigraphic units have been mapped and the eruptive fissure configuration identified. Fieldwork data were improved by highresolution orthoimages and DEM analysis, producing a map with detailed lava flow boundaries. In order to synthesize the main phases of the West Rift evolution, lithostratigraphic units were grouped into synthems. The volcanic succession starts with the oldest Etna subaerial lava flows (Adrano Synthem), unconformably covered by lavas belonging to Acireale and Concazze Synthems. Mongibello volcanic succession (Il Piano Synthem) widely crops out in the area as several superposed lava flow fields. They are generated by more than 40 eruptive fissures in the past 15,000 years forming the core of theWest Rift. The eruptive fissures (strike 245 to 280 ) fed several monogenetic cones located in the central sector of the western flank. Some fissures were formed in the last 2,000 years. The result of this work is a geological map at 1:15,000 scale, highlighting the geological and structural setting of the area and significantly improving the knowledge of West Rift evolution, in order to better assess the entire eruptive history and structural framework of Mt Etna.