Anatahan | U.S. Geological Survey Official websites use .gov .gov website belongs to an official government organization in the United States. Secure .gov websites use HTTPS lock ( or means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites. Anatahan Find U.S. Volcano Filters The map displays volcanoes, earthquakes, monitoring instruments, and past lava flows. Get Help Earthquake Plots To view an earthquake cross-sectional plot, click "Draw Plot" to start drawing on the map. Once the plot area is selected, click on "View Plot" to view chart or "Clear Plot" to start over. Map Layers Earthquake Colors Earthquake Depth Units Earthquake Time Units Results Filters The map displays volcanoes, earthquakes, monitoring instruments, and past lava flows. Get Help Earthquake Plots To view an earthquake cross-sectional plot, click "Draw Plot" to start drawing on the map. Once the plot area is selected, click on "View Plot" to view chart or "Clear Plot" to start over. Settings Map Layers Earthquake Colors Earthquake Depth Units Earthquake Time Units Map Legend Map Legend Results Anatahan Multimedia Publications News Connect The elongate, 9-km-long island of Anatahan in the central Mariana Islands consists of large stratovolcano with a 2.3 x 5 km, E-W-trending compound summit caldera. Quick Facts Location: Commonwealth of the Northern Mariana Islands Latitude: 16.35° N Longitude: 145.67° E Elevation: 790 (m) 2,592 (f) Volcano type: Stratovolcano Composition: Basalt - Dacite Most recent eruption: 2008 CE Threat Potential: Moderate* *based on the National Volcano Early Warning System Summary The elongate, 9-km-long island of Anatahan in the central Mariana Islands consists of large stratovolcano with a 2.3 x 5 km, E-W-trending compound summit caldera. The larger western portion of the caldera is 2.3 x 3 km wide, and its western rim forms the island's 790-m high point. Ponded lava flows overlain by pyroclastic deposits fill the floor of the western caldera, whose SW side is cut by a fresh-looking smaller crater. The 2-km-wide eastern portion of the caldera contained a steep-walled inner crater whose floor prior to the 2003 eruption was only 68 m above sea level. A submarine volcano, NE Anatahan, rises to within 460 m of the sea surface on the NE flank of the volcano, and numerous other submarine vents are found on the NE-to-SE flanks. Sparseness of vegetation on the most recent lava flows on Anatahan had indicated that they were of Holocene age, but the first historical eruption of Anatahan did not occur until May 2003, when a large explosive eruption took place forming a new crater inside the eastern caldera. From the Smithsonian Global Volcanism Program Volcano Watch — Why monitor volcanoes of the Commonwealth of Northern Mariana Islands? June 22, 2006 Volcano Watch — Why monitor volcanoes of the Commonwealth of Northern Mariana Islands? Volcano Watch — Anatahan Volcano's ash clouds reach new heights July 21, 2005 Volcano Watch — Anatahan Volcano's ash clouds reach new heights Volcano Watch — Anatahan Volcano reawakens April 29, 2004 Volcano Watch — Anatahan Volcano reawakens View All July 19, 2019 Volcanic hazards in the Pacific U.S. Territories Volcanic hazards in the Pacific U.S. Territories The Commonwealth of the Northern Mariana Islands, Guam, and American Samoa lie along the western side of the famed Pacific Ring of Fire. Here, the processes of active island and submarine volcanoes produce activity both underwater and in the atmosphere that poses potential hazards to the daily lives of residents and travelers. Since 2000, CNMI volcanoes have erupted six times, and one... Authors Gabrielle Tepp, Brian Shiro, William W. Chadwick By Volcano Hazards Program Volcano Science Center Agrigan Ahyi Seamount Alamagan Anatahan Asuncion Daikoku Seamount East Diamante Esmeralda Bank Farallon de Pajaros Fukujin Seamount Guguan Kasuga 2 Maug Islands Ofu-Olosega Pagan Ruby Sarigan South Sarigan Seamount Supply Reef Ta'u Island Tutuila Island Zealandia Bank Subduction Zone Science October 22, 2018 2018 update to the U.S. Geological Survey national volcanic threat assessment 2018 update to the U.S. Geological Survey national volcanic threat assessment When erupting, all volcanoes pose a degree of risk to people and infrastructure, however, the risks are not equivalent from one volcano to another because of differences in eruptive style and geographic location. Assessing the relative threats posed by U.S. volcanoes identifies which volcanoes warrant the greatest risk-mitigation efforts by the U.S. Geological Survey and its partners... Authors John W. Ewert, Angela K. Diefenbach, David W. Ramsey By Volcano Hazards Program Volcano Science Center Agrigan Ahyi Seamount Alamagan Anatahan Asuncion Belknap Black Butte Crater Lava Field Black Rock Desert Volcanic Field Blue Lake Crater Carrizozo Lava Flow Cascade Range Weekly Update Cinnamon Butte Clear Lake Volcanic Field Coso Volcanic Field Crater Lake Craters of the Moon Volcanic Field Daikoku Seamount Davis Lake Volcanic Field Devils Garden Lava Field Diamond Craters Volcanic Field Dotsero Volcanic Center East Diamante Esmeralda Bank Farallon de Pajaros Fukujin Seamount Glacier Peak Guguan Haleakalā Hell's Half Acre Lava Field Hualālai Indian Heaven Volcanic Field Jordan Craters Volcanic Field Kama‘ehuakanaloa Kasuga 2 Kīlauea Lassen Volcanic Center Long Valley Caldera Mammoth Mountain Markagunt Plateau Volcanic Field Maug Islands Mauna Kea Mauna Loa Medicine Lake Mono Lake Volcanic Field Mono-Inyo Craters Mount Adams Mount Bachelor Mount Baker Mount Hood Mount Jefferson Mount Rainier Mount Shasta Mount St. Helens Newberry Ofu-Olosega Pagan Red Hill-Quemado Volcanic Field Ruby Salton Buttes San Francisco Volcanic Field Sand Mountain Volcanic Field Sarigan Soda Lakes South Sarigan Seamount Supply Reef Ta'u Island Three Sisters Tutuila Island Ubehebe Craters Uinkaret Volcanic Field Valles Caldera Wapi Lava Field Weekly Update West Crater Volcanic Field Yellowstone Zealandia Bank Zuni-Bandera Volcanic Field January 1, 2005 Anatahan, Northern Mariana Islands: Reconnaissance geological observations during and after the volcanic crisis of spring 1990, and monitoring prior to the May 2003 eruption Anatahan, Northern Mariana Islands: Reconnaissance geological observations during and after the volcanic crisis of spring 1990, and monitoring prior to the May 2003 eruption Anatahan island is 9.5 km east–west by 3.5 km north–south and truncated by an elongate caldera 5 km east–west by 2.5 km north–south. A steep-walled pit crater ∼1 km across and ∼200 m deep occupies the eastern part of the caldera. The island is the summit region of a mostly submarine stratovolcano. The oldest subaerial rocks (stage 1) are exposed low on the outer flanks and in the caldera... Authors S.K. Rowland, J. P. Lockwood, F. A. Trusdell, R. B. Moore, M. K. Sako, R. Y. Koyanagi, G. Kojima By Natural Hazards Mission Area Volcano Hazards Program Volcano Science Center Anatahan View All Quick Facts Location: Commonwealth of the Northern Mariana Islands Latitude: 16.35° N Longitude: 145.67° E Elevation: 790 (m) 2,592 (f) Volcano type: Stratovolcano Composition: Basalt - Dacite Most recent eruption: 2008 CE Threat Potential: Moderate* *based on the National Volcano Early Warning System Volcanoes Hazards Program Links Assess Prepare Forecast Activity Products Observatories About Was this page helpful?