Northern Mariana Islands Recent Status Report, Updates, and Information Releases
PAGAN VOLCANO (CAVW #0804-17=)
18°7'48" N 145°48' E, Summit Elevation 1870 ft (570 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW
Report prepared by the U.S. Geological Survey.
Gas and steam plumes continued to be observed in MODIS satellite data throughout the week. Researchers camped on the island reported finding trace amounts of granular sand-sized ash on tent surfaces this morning. It is believed that the ash emission occurred during the night. No ash emissions have been detected during the day, today but a steam plume has been continuously observed.
Pagan is not monitored with ground-based geophysical instrumentation and the only source of information is satellite observation and occasional reports from observers who visit the island. We will continue to evaluate satellite imagery and on-island reports when they become available, but because the volcano is not monitored with ground-based instruments, we cannot provide advanced warning of activity. A research crew is planned to be on the island until the end of May.
Access to the island may be restricted by the CNMI government. Contact the Emergency Management Office to get the latest information.
Pagan is the largest of the Northern Islands. Pagan Island consists of two volcanoes: Mount Pagan on the north and South Pagan Volcano on the south. Mount Pagan is a stratovolcano that is growing within a 6-km-diameter caldera formed less than 9,400 years ago. South Pagan volcano is a large young stratovolcano with a summit caldera 2.8 km across. There are no known historical eruptions of South Pagan volcano. Mount Pagan is one of the most historically active volcanoes in the Northern Marianas. Its most recent large (VEI 4) eruption was in 1981. The volcano was intermittently active through 1996, producing mainly light ashfall from a column that would occasionally reach 10,000 feet above sea level. Following the 1981 eruption, destructive rain-triggered (secondary) debris flows buried large tracts of land, including the site of a village that contained a school, dispensary, church, power generating buildings, cisterns and associated infrastructure.
Mount Pagan is possibly the most dangerous volcano in the Northern Marianas. It is frequently active, and a full spectrum of acutely hazardous phenomena such as pyroclastic flows and surges, directed blasts, and secondary lahars (volcanic debris flows) have affected the relatively flat land close to the volcano; areas that are attractive for settlement. All known historical eruptions have originated at the central stratovolcano, but eruptions from flank or satellitic vents are possible. For instance, a large maar, with extensive surge deposits, formed on the west flank of Mount Pagan about 200 years ago.
ANATAHAN VOLCANO (CAVW #0804-20=)
16°21' N 145°40'12" E, Summit Elevation 2592 ft (790 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN
Report prepared by the U.S. Geological Survey.
No reports of eruptive activity at Anatahan were received during the past week. Seismic activity remains low. Nothing unusual was observed in satellite images throughout the week.
During times of northerly winds, the Anatahan plume, if present, could be directed towards the CNMI and Guam. If this happens, residents may notice hazy air conditions and smell sulfur. The Emergency Management Office (EMO) of the CNMI government will issue volcanic haze and sulfur advisories if appropriate.
Access to the island may be restricted by the CNMI government. Contact the EMO for the latest information.
CONTACT INFORMATION:
USGS Northern Marianas Duty Scientist (808) 967-8815
http://volcano.wr.usgs.gov/cnmistatus.php
CNMI Emergency Management Office (670) 322-8001
http://www.cnmiemo.gov.mp/
