Report on Pagan (United States) — November 1981
Scientific Event Alert Network Bulletin, vol. 6, no. 11 (November 1981)
Managing Editor: Lindsay McClelland.
Pagan (United States) Tephra ejection
Please cite this report as:
Global Volcanism Program, 1981. Report on Pagan (United States). In: McClelland, L. (ed.), Scientific Event Alert Network Bulletin, 6:11. Smithsonian Institution.
18.13°N, 145.8°E; summit elev. 570 m
All times are local (unless otherwise noted)
Residents of Pagan Island . . . returned for a 1-day visit on 19 November. Explosive activity was occurring when they arrived about 0600 and continued through the day, accompanied by booming sounds. Scoria fell on the visitors, who also noted a strong odor of sulfur. At about 1700, a series of booming sounds was followed by ejection of a tephra column that rose about 1.5 km. Since a previous visit in September, 1 cm of ash had accumulated on the island's only village, 4 km from the summit.
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.
Information Contacts: N. Banks, HVO.