Report on Pagan (United States) — 6 December-12 December 2006
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 6 December-12 December 2006
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2006. Report on Pagan (United States). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 6 December-12 December 2006. Smithsonian Institution and US Geological Survey.
18.13°N, 145.8°E; summit elev. 570 m
All times are local (unless otherwise noted)
During 4-5 December, residents 3 km SW of Pagan reported ashfall that accumulated in their camp at a rate of about 6.4 mm per day. They also described a plume from the summit that rose to an altitude of 640 m (2,100 ft) a.s.l. and a sulfur smell that occasionally wafted through their camp. Based on satellite imagery, the Washington VAAC reported a gas-and-ash plume that drifted mainly W on 5, 6, and 8 December. Satellite imagery showed no further activity through 11 December.
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.
Sources: Emergency Management Office of the Commonwealth of the Mariana Islands and United States Geological Survey Volcano Hazards Program, US Geological Survey Volcano Hazards Program, Washington Volcanic Ash Advisory Center (VAAC)