AVO Logo
Site Map | FAQ |
Alaska Volcano Observatory
About Alaska's Volcanoes | Map & Alphabetical List | Interactive Map | Latitude/Longitude List | Eruption Search | Volcano Search | Tanaga 
You are here: Home > Volcano Information > Tanaga

Tanaga Volcano description and information

TANAGA LINKS

SAMPLES

Webicorders
LOCATION
FACTS
Official Name: Tanaga Volcano
Type:Stratovolcano with two flanking stratovolcanoes
Most Recent Activity:1914
Seismically Monitored: Yes
Color Code:GREEN
Alert Level:NORMAL
Elevation: 5925 ft (1806 m)
Latitude: 51.884° N
Longitude:178.143° W
Quadrangle:Gareloi Island Adak
CAVW Number:311080
Associated Features:Sajaka Two
East Tanaga
Nearby towns:Adak 65 mi (104 km) SE
Atka 169 mi (272 km) NE
Shemya Station 180 mi (289 km) NW
Attu Station 219 mi (352 km) NW
Anchorage 1239 mi (1994 km) NE
DESCRIPTION
Tanaga Island lies in the Andreanof Islands approximately 100 km (62 miles) west of the community of Adak and 2025 km (1260 miles) SW of Anchorage. The northern half of the island is home to the Tanaga volcanic complex, comprising three main volcanic edifices. Tanaga volcano is the tallest of these (1,806 m or 5,925 ft) and lies in the center of the complex. The last known eruption of Tanaga occurred in 1914 and earlier eruptions were reported in 1763-1770, 1791, and 1829. Reports of these eruptions are vague, but deposits on the flanks of the volcano show that typical eruptions produce blocky lava flows and occasional ash clouds. Eruptions have occurred both from the summit vent and a 1,584 m (5,197 ft)-high satellite vent on the volcano's northeast flank. Immediately west of Tanaga volcano lies Sajaka, a 1,354 m (4,443 ft)-high compound edifice with an older cone to the east that collapsed into the sea within the last few thousand years, and a new cone that has grown in the breach. The new cone is 1,312 m (4,305 ft) high and consists of steeply dipping, interbedded cinders and thin, spatter-fed lava flows. To the east of Tanaga lies Takawangha, which is separated from the other active volcanic vents by a ridge of older rock. Takawangha's 1,449 m (4,754 ft)-high summit is mostly ice-covered, except for four young craters that have erupted ash and lava flows in the last few thousand years. Parts of Takawangha's edifice are hydrothermally altered and may be unstable, and could produce localized debris avalanches. No historical eruptions are known from Sajaka or Takawangha; however, field work shows that recent eruptions have occurred and it is possible that historic eruptions attributed only to Tanaga may instead have come from these other vents.
Contact AVO Privacy Accessibility Information Quality FOIA
URL: www2.avo.alaska.edu/volcanoes/volcinfo.php
Page modified: June 12, 2014 07:20
Contact Information: AVO Web Team

twitter @alaska_avo
facebook alaska.avo
email Receive volcano updates by email: USGS VNS