Kasatochi Volcano is a small island in the Aleutians, northeast of Adak and 10 miles northwest of the west end of Atka Island.
There is a saltwater lake at the bottom of the 4000-foot wide crater, probably less than 200 feet above sea level. The east rim of the crater was the highest point before the 2008 eruption, at 1030 feet.
On August 7, 2008, Kasatochi erupted violently, spewing an ash plume 50,000 feet high. At least 40 commercial airline flights were cancelled as a result. The eruption lasted about 24 hours, and completely covered the island with ash, rocks, and other debris. Before this, Kasatochi had no confirmed historical eruptions, and no seismic instruments were on the island.
On August 4, two USFWS personnel on the island felt small tremors are reported them to the Alaska Volcano Observatory. By early evening August 6, it became clear that a significant volcanic earthquake swarm was occurring in the vicinity of Kasatochi Island. At about 7 PM, the Alaska Volcano Observatory issued a formal Volcanic Activity Notice and recommended that the scientists on the island be evacuated as soon as possible.
The volcano erupted just after 2 PM the following afternoon, less than 30 minutes after a local fishing boat evacuated the two scientists from the island. Following the eruption, thick deposits of gray volcanic debris and ash covered the formerly lush island that was home to over a hundred thousand seabirds. A 75-year-old USFWS cabin on the island had disappeared, either swept from the island or buried beneath the debris.
Getting There and Climbing
Private or chartered boat or helicopter are the common methods of transportation to the island. Adak Island has scheduled commercial air transportation, and Atka Island has a small airport with air taxi service.
The Kasatochi cauldera can be approached by landing on the south or east shores of the island, with a moderately steep climb on loose debris to the top. The cliffs are new and unstable, and the steep slopes are loose and can slide.
Prior to the 2008 eruption, there was a sea lion rookery on the north side of the island, and access was (and might still be) restricted by the USFWS. Research is currently being done on the re-establishment of life on the island.
External LinksAlaska Volcano Observatory, Kasatochi Volcano
Wikipedia, Kasatochi Island
Photos from Kasatochi, prior to 2008 eruption