Report on Pagan (United States) — 5 May-11 May 2010
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 5 May-11 May 2010
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2010. Report on Pagan (United States) (Sennert, S, ed.). Weekly Volcanic Activity Report, 5 May-11 May 2010. Smithsonian Institution and US Geological Survey.
18.13°N, 145.8°E; summit elev. 570 m
All times are local (unless otherwise noted)
Steam and gas plumes from Pagan were seen in satellite imagery on 28 April (UTC) and 3 May; no unusual thermal activity was identified. A visitor to the island saw a minor ash emission on the morning of 3 May. The Aviation Color Code was raised to Yellow and the Volcano Alert Level was raised to Advisory on 6 May based on the recent satellite observations and confirmed minor ashfall on the island.
Geological Summary. 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. North Pagan at the NE end of the island rises above the flat floor of the northern caldera, which may have formed less than 1,000 years ago. South Pagan is a stratovolcano with an elongated summit containing four distinct craters. Almost all of the recorded eruptions, which date back to the 17th century, have originated from North Pagan. The largest eruption during historical time took place in 1981 and prompted the evacuation of the sparsely populated island.