The Emplacement of Silicic Domes and Lava Flows
Eruptive histories of Lipari and Vulcano, Italy, during the past 22,000 years
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Published:January 01, 1987
Silicic volcanism in the central Aeolian Islands of Lipari and Vulcano has followed a consistent pattern during the past 22,000 years. Active eruptive cycles generally began with hydrovolcanic breccias, surge beds, and ash-fall deposits. They ended with magmatic effusions that formed lava domes and short coulees. Long repose periods separated shorter active cycles. Eruptions occurred from both isolated vents located along fissures (e.g., domes of southern Lipari) and central vents with a long history of activity and repose (e.g., Fossa cone of Vulcano). The compositions of the juvenile products include leucite tephrite, trachyte, and rhyolite.
The average volume of silicic products in an eruptive cycle on Lipari and Lentia was about 5 × 108 m3 of juvenile magma. The repose period between major active periods was about 4,000 years. The production rate for the period of 22,000 years ago to the present was 105 m3 per year. The average volume of erupted material in an active cycle at Fossa (other than the Punte Nere cycle) was about 2 × 107 m3 of juvenile magma. Repose times between cycles range from 300 to 800 years. The rate of magma production for the entire Fossa cone during its 6,000-year growth was 5 × 104 m3 per year. Vulcanello produced about 3 × 107 m3 of tephritic to trachytic magma in the past 2,100 years, a production rate of 1.5 × 104 m3 per year.