"The 2014 unrest was the first significant departure from background at Semisopochnoi since installation of the seismic network in 2005. The volcano is remote, and aerial reconnaissance by AVO staff was determined to be too costly to obtain. At roughly 32 by 56 kilometers (20 by 35 miles), the island lies roughly 1,700 kilometers (1,100 miles) from mainland Alaska.

The epicenter was at a depth of 62.2 …

Denali, the Indian name for the peak, means "The Great One." They extend about 110 miles (175 km) southeast of the Near Islands and west of the Andreanof Islands. Semisopochnoi is monitored with an on-island seismic network and remotely by satellite and lightning sensors. The largest of the islands are Amchitka, Kiska, and Semisopochnoi. Attu Station, a former Coast Guard LORAN station, is located at 52°51′N 173°11′E. Denali, the Indian name for the peak, means "The Great One." It formed as a result of collapse of a low-angle, dominantly basaltic volcano following the eruption of a large volume of dacitic pumice. The Yukon River, almost 2,000 miles … The island was the site of the only World War II land battle fought on American soil in general and in the continental United States (the Battle of Attu ), and its battlefield area is a U.S. National Historic Landmark .  / … The interior is extremel y rugged and mountainous; only the lower slopes are grass covered. Mountain (climbing) weather forecasts for 2 elevations of Semisopochnoi, Aleutian Islands, Alaska/Yukon Ranges, United States. Weather clouds continued to obscure views of the volcano.

Water Bodies. The Yukon River, almost 2,000 miles … Water Bodies.

In clear weather this It sits approximately two thirds of the way along the Aleutian Island chain toward Kamchatka. It is the westernmost of Alaska’s Aleutian Islands, even farther west than the Hawaiian Islands. Attu Station, a former Coast Guard LORAN station, is located at 52°51′N 173°11′E.

... What was the weather like at that time? Semisopochnoi is monitored with an on-island seismic network and remotely by satellite and lightning sensors. Of the 20 highest peaks in the United States, 17 are in Alaska. US Dept of Commerce National Oceanic and Atmospheric Administration National Weather Service Anchorage Volcanic Ash Advisory Center 6930 Sand lake Road Semisopochnoi, the largest subaerial volcano of the western Aleutians, is 20 km wide at sea level and contains an 8-km-wide caldera. It is the westernmost of Alaska’s Aleutian Islands, even farther west than the Hawaiian Islands. GEOLOGIC RECONNAISSANCE OF SEMISOPOCHNOI ISLAND, WESTERN ALEUTIAN ISLANDS, ALASKA By ROBERT R. COATS ABSTRACT Semisopochnoi Island, the largest of the young volcanic islands of the western Aleutians, is the easternmost of the Rat Island group, and is near the southern extremity of the great Aleutian arc. Separated from the Andreanof Islands by Amchitka The island was the site of the only World War II land battle fought on American soil in general and in the continental United States (the Battle of Attu ), and its battlefield area is a U.S. National Historic Landmark . There are two prominent peaks, one 3,897 feet high in the NE part, and the other 1,960 feet high in the S part.

Posted by agimarc on 2015-03-29. Posted in: America N, ... Semisopochnoi Island is a basalt volcanic island some 2,100 km southwest from Anchorage. Furthermore, an infrasound array on Adak Island may detect explosive emissions from Semisopochnoi with a 13 minute delay if atmospheric conditions permit. Denali, the highest peak in North America, is 20,320 ft. above sea level. Furthermore, an infrasound array on Adak Island may detect explosive emissions from Semisopochnoi with a 13 minute delay if atmospheric conditions permit. Kanaga Island , across Adak Strait from Adak Island, is roughly right -angled and extends 18 miles N and S, 28 miles E and W, and has a maximum width of 7 miles. Facts About Alaska Mountains. Of the 20 highest peaks in the United States, 17 are in Alaska.

Throughout the sequence, no surface activity was noted in the few clear-weather views of the island.

Little Sitkin Island , 32.5 miles W of Semisopochnoi Island, has a N -S length of 5.5 miles and an E -W width of the same distance. Furthermore, an infrasound array on Adak Island may detect explosive emissions from Semisopochnoi with a 13 minute delay if atmospheric conditions permit.  / … On Wednesday, December 19, AVO lowered the Aviation Color Code to UNASSIGNED and Alert Level to UNASSIGNED for Semisopochnoi due to the lack of evidence for ongoing eruptive activity.