Alaska hosts within its borders over 80 major volcanic centers that
have erupted during the past 10,000 years. At least 29 of these volcanic centers
had historical eruptions and 12 additional volcanic centers may have had
historical eruptions. Historical in Alaska generally means the period
since 1760 when explorers, travelers, and inhabitants kept written records.
These 41 volcanic centers have been the source for more than 256 historical
eruptions reported from Alaska volcanoes.
1840-1870: Historical literature refers to several episodes
of small tephra-producing events in the mid 1800s, and increased
fumarolic activity began in Sherman Crater near the summit in 1975 and
remains elevated today.
Glacier Peak
17th - 18th centuries: Between about 200 and 300 years ago,
small eruptions deposited pumice and ash east of the volcano, and may
have been observed by Native Americans.
Mount Rainier
1894 & early 1800s: Several eyewitness accounts
describe minor releases of steam and ash-laden steam during November
and December 1894. The most recent eruption that formed a thin and
discontinuous tephra layer, however, occurred during the first half of
the 19th century.
Mount St. Helens
1980-1986: Large explosive eruption on May 18, 1980,
followed by 21 smaller eruptive episodes. The last 17 episodes built a
lava dome in the volcano's crater.
1800-1857: Large explosive eruption in 1800 was followed by
extrusions of lava that formed a lava flow on the volcano's northwest
flank (Floating Island lava flow) and a lava dome on the north flank
(Goat Rocks lava dome).
Late 1700s: Layers of volcanic rocks record a variety of
activity related to the growth of a lava dome at the volcano's summit,
including pyroclastic flows, lahars, and tephra fall.
1856-1865 & late 1700s: According to eyewitnesses,
small explosive eruptions occurred from the summit area between 1856
and 1865. In the latter half of the 18th century, however, a lava dome
was erupted, which was accompanied by pyroclastic flows, lahars, and
tephra fall.
1786: An eruption cloud was observed above the volcano from
a ship passing by north coast California, and the activity included
pyroclastic flows.
Lassen Peak
1914-1917: A series of small explosions that began on May
30, 1914, was followed 12 months later by extrusion of lava from the
summit and a destructive pyroclastic flow and lahars on May 21, 1915.
Minor activity continued through middle of 1917. See fact sheet, Eruptions
of Lassen Peak, 1914-1917 (PDF).
1790-present, eruption
summary table: First written record of eruption at Kilauea was in
1823; strong explosive activity occurred in 1790.
Mauna Loa Volcano, Hawai`i
1832-present, eruption
summary table: First written record of eruption at Mauna Loa was in
1832 (eyewitness was on Maui, 190 km away).
Hualalai Volcano, Hawai`i
late 1700s - 1801: Six different vents erupted lava between the late
1700s and 1801, two of which generated lava flows that poured into the sea
on the west coast of Hawai`i.
East Mau`i Volcano (Haleakala), Mau`i
1790: Two lava flows erupted on the southwest flank and reached the
sea.
U.S. Department of the Interior, U.S. Geological Survey, Menlo Park, California, USA
URL http://volcanoes.usgs.gov/Volcanoes/Historical.html
Contact: VHP WWW Team
| USGS
Privacy Statement | USGS
Disclaimer | Accessibility
|
Last modification: Sunday, 03-Jun-2001 00:19:23 EDT
(SRB)
