Sete Cidades - São Miguel, Açores, Portugal
Posted by: tmob
N 37° 50.364 W 025° 47.707
26S E 606017 N 4188680
Quick Description: Sete Cidades volcano is located at the western end of São Miguel Island and contains a 5-km-wide summit caldera, occupied by two caldera lakes
Location: Arquipélago dos Açores, Portugal
Date Posted: 1/10/2012 2:53:52 AM
Waymark Code: WMDFP6
«Sete Cidades volcano at the western end of Sao Miguel Island contains a 5-km-wide summit caldera, occupied by two caldera lakes, that is one of the scenic highlights of the Azores.
The steep-walled, 500-m-deep caldera was formed about 22,000 years ago, and at least 22 post-caldera eruptions have occurred.
A large group of Pleistocene post-caldera trachytic lava domes, lava flows, and pyroclastic-flow deposits is found on the western-to-northern flanks. A nearly circular ring of six Holocene pyroclastic cones occupies the caldera floor.
These have been the source of a dozen trachytic pumice-fall deposits erupted during the past 5000 years. Sete Cidades is one of the most active Azorean volcanoes. Historical eruptions date back to the 15th century and have occurred from within the caldera and from submarine vents off the west coast.»
Volcano Number: 1802-08=
Volcano Type: Stratovolcano
Volcano Status: Historical
Last Known Eruption: 1880
Summit Elevation: 856 m
«Sete Cidades has erupted at least eight times since ca. 1444, with six of these eruptions from submarine vents west of the volcano. The eruption in 1638 formed the ephemeral islet of Sabrina. Subaerial eruptions include a large explosive event on the southwest side of the caldera in 1444 and on the west flank of the volcano, at Pico das Camarinhas, in 1713. The most recent eruption was from a submarine vent in 1880.»