Report on Pagan (United States) — 21 April-27 April 2010
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 21 April-27 April 2010
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2010. Report on Pagan (United States). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 21 April-27 April 2010. Smithsonian Institution and US Geological Survey.
18.13°N, 145.8°E; summit elev. 570 m
All times are local (unless otherwise noted)
A gas plume from Pagan was seen in satellite imagery on 21 and 22 April (UTC). The Volcano Alert Level and the Aviation Color Code remained "Unassigned." There are no monitoring instruments on Pagan, thus the levels "Green" or "Normal" do not apply because background activity is not defined. Monitoring is done by satellite and ground observers.
Geologic Background. Pagan Island, the largest and one of the most active of the Mariana Islands volcanoes, consists of two stratovolcanoes connected by a narrow isthmus. Both North and South Pagan stratovolcanoes were constructed within calderas, 7 and 4 km in diameter, respectively. The 570-m-high Mount Pagan at the NE end of the island rises above the flat floor of the northern caldera, which may have formed less than 1000 years ago. South Pagan is a 548-m-high stratovolcano with an elongated summit containing four distinct craters. Almost all of the historical eruptions of Pagan, which date back to the 17th century, have originated from North Pagan volcano. The largest eruption of Pagan during historical time took place in 1981 and prompted the evacuation of the sparsely populated island.