Report on Pagan (United States) — 27 January-2 February 2016
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 27 January-2 February 2016
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2016. Report on Pagan (United States). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 27 January-2 February 2016. Smithsonian Institution and US Geological Survey.
18.13°N, 145.8°E; summit elev. 570 m
All times are local (unless otherwise noted)
Satellite data and ground-based observations from a field crew and local residents near Pagan indicated that steam-and-gas emissions have significantly decreased since March 2015. The Aviation Color Code and Volcano Alert Level were lowered to Unassigned on 30 January.
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.