42.60 N, 11.93 E
summit elevation 800 m
Vulsini volcano is located 87 km NNW of Rome. It consists of a volcanic depression occupied by lake Bolsena (Lago di Bolsena). Vulsini volcano is part of the Roman Magmatic Province of the Central Tyrrhenian area.
Isola Martana is a young post-caldera cone in the SW edge of Lago di Bolsena. A drainage system constructed by Romans, to divert water from the host springs at the nothern margin of Viterbo.
Previous eruptions have occurred at 4 main centres along a line of weakness. There is no geological evidence for the eruption of 104 BC, but historical records record it.
The caldera is elliptical elongated NNE-SSW, with axes of 9 and 7 km. The northern and eastern rims are well preserved and rise over 200 m above the caldera floor. The eastern rim cuts a volcano-tectonic depression which is partially filled by Lake Bolsena.
A small depression at Vulsini volcano is located in the northwestern sector of Latera
Caldera. The depression is called Vepe Caldera and containsLake Mezzano.
Eruptions 170,000 years ago were the largest in the history of Vulsini volcano. The eruptions produced widespread pyroclastic flows around the present caldera. The Onano eruption was located in a structurally weak area between the eastern rim of Latera caldera and the western edge of Bolsena volcano-tectonic depression.
Eruption of Vulsini in 104 BC
Onana eruption 170,000 years ago.