New Eddystone Rock an
Alaska
Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S., ...
n island located in
Behm Canal Behm Canal is a natural channel in the Alexander Archipelago, in the southeastern part of the U.S. state of Alaska.
About long, Behm Canal separates Revillagigedo Island from the mainland. From the Clarence Strait, Behm Canal extends north and n ...
, about east of
Ketchikan
Ketchikan ( ; tli, Kichx̱áan) is a city in and the borough seat of the Ketchikan Gateway Borough of Alaska. It is the state's southeasternmost major settlement. Downtown Ketchikan is a National Historic District.
With a population at the 202 ...
. It is a pillar of
basalt
Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial ...
.
Geology
During the last ice age,
Southeast Alaska
Southeast Alaska, colloquially referred to as the Alaska(n) Panhandle, is the southeastern portion of the U.S. state of Alaska, bordered to the east and north by the northern half of the Canadian province of British Columbia (and a small part ...
was covered by a thick ice sheet. The weight of the ice pressed down and compressed the underlying crust, including the area that is now Behm Canal. As the ice melted at the beginning of the current
interglacial period
An interglacial period (or alternatively interglacial, interglaciation) is a geological interval of warmer global average temperature lasting thousands of years that separates consecutive glacial periods within an ice age. The current Holocene in ...
, this weight was reduced. The
Earth's crust
Earth's crust is Earth's thin outer shell of rock, referring to less than 1% of Earth's radius and volume. It is the top component of the lithosphere, a division of Earth's layers that includes the crust and the upper part of the mantle. The ...
responded by flexing upward, a process known as
isostatic rebound
Post-glacial rebound (also called isostatic rebound or crustal rebound) is the rise of land masses after the removal of the huge weight of ice sheets during the last glacial period, which had caused isostatic depression. Post-glacial rebound a ...
. This movement broke the rock and created a New Eddystone volcano that erupted 15,000 to 13,800 years ago.
The volcano rises from the bottom of Behm Canal, about below sea level. The island stands to above sea level, giving the volcano a total height of over . While the portion of the volcano below sea level is somewhat cone-shaped, wave action over the millennia has eroded all the rock above sea level except the dense, spire-shaped volcanic plug.
Bathymetric
Bathymetry (; ) is the study of underwater depth of ocean floors (''seabed topography''), lake floors, or river floors. In other words, bathymetry is the underwater equivalent to hypsometry or topography. The first recorded evidence of water de ...
studies of the floor of Behm Canal show that New Eddystone was not the only volcano that emerged as the crust buckled. Four other vents have been identified. Two are dome-shaped, suggesting that they erupted below the glacial ice sheet and were rounded off as the ice flowed over them. The other two, and New Eddystone Rock, are more pointed showing that they had never been overridden by ice. Of the five identified volcanic vents in Behm Canal, only New Eddystone Rock rises above sea level.
The tidal range in Behm canal exceeds . Since much of New Eddystone Rock is low-lying beach, the size of the island above the water varies considerably with the tides.
History
![New Eddystone Rock engraving](https://upload.wikimedia.org/wikipedia/commons/0/0a/New_Eddystone_Rock_engraving.jpg)
How the native
Tlingit
The Tlingit ( or ; also spelled Tlinkit) are indigenous peoples of the Pacific Northwest Coast of North America. Their language is the Tlingit language (natively , pronounced ), people discovered the island, their name for it, and what role it played in their lives prior to European contact is lost to history.
The first European to observe New Eddystone Rock was
Captain George Vancouver
Captain George Vancouver (22 June 1757 – 10 May 1798) was a British Royal Navy officer best known for his 1791–1795 expedition, which explored and charted North America's northwestern Pacific Coast regions, including the coasts of what a ...
. He was dispatched by the
British Admiralty
The Admiralty was a department of the Government of the United Kingdom responsible for the command of the Royal Navy until 1964, historically under its titular head, the Lord High Admiral – one of the Great Officers of State. For much of it ...
in 1791 to survey the northwest coast of North America. By July 1793 Vancouver's multi-year voyage brought him to what is now
Observatory Inlet
Observatory Inlet is an inlet on the North Coast of British Columbia. It is a northward extension of Portland Inlet, other branches of which include the Portland Canal. The entrance of Observatory Inlet, from Portland Inlet, lies between Ramsden ...
,
British Columbia
British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...
. He anchored his ships there and then led a two-boat surveying team north along the shore. He commanded
HMS ''Discovery's'' yawl, and
Lieutenant Peter Puget commanded ''Discovery's'' launch.
Exploring north through Behm Canal, Vancouver reached New Eddystone Rock on Friday, August 9, 1793. He beached his boats there. In his report to
King George III
George III (George William Frederick; 4 June 173829 January 1820) was King of Great Britain and of Ireland from 25 October 1760 until the union of the two kingdoms on 1 January 1801, after which he was King of the United Kingdom of Great Br ...
, he wrote,
We stopped to breakfast and whilst we were thus engaged, three small canoes, with about a dozen of the natives, landed and approached us unarmed, and with the utmost good humor accepted such presents as were offered to them, making signs in return, that they had brought nothing to dispose of, but inviting us in the most pressing manner to their habitations
![John Lynn - Smeaton's Eddystone Lighthouse](https://upload.wikimedia.org/wikipedia/commons/3/37/John_Lynn_-_Smeaton%27s_Eddystone_Lighthouse.jpg)
Vancouver chose not to accept the invitation, but instead continued exploring north. He named the island for the
Eddystone lighthouse
The Eddystone Lighthouse is a lighthouse that is located on the dangerous Eddystone Rocks, south of Rame Head in Cornwall, England. The rocks are submerged below the surface of the sea and are composed of Precambrian gneiss. View at 1:50000 ...
off
Plymouth, England
Plymouth () is a port city and unitary authority in South West England. It is located on the south coast of Devon, approximately south-west of Exeter and south-west of London. It is bordered by Cornwall to the west and south-west.
Plymouth' ...
, a pillar that also erupted from a narrow base at sea level.
Much of Southeast Alaska, including New Eddystone Rock, was incorporated into
Tongass National Forest
The Tongass National Forest () in Southeast Alaska is the largest U.S. National Forest at . Most of its area is temperate rain forest and is remote enough to be home to many species of endangered and rare flora and fauna. The Tongass, which i ...
through a series of proclamations by
President Theodore Roosevelt
Theodore Roosevelt Jr. ( ; October 27, 1858 – January 6, 1919), often referred to as Teddy or by his initials, T. R., was an American politician, statesman, soldier, conservationist, naturalist, historian, and writer who served as the 26t ...
. On December 1, 1978
President Jimmy Carter
James Earl Carter Jr. (born October 1, 1924) is an American politician who served as the 39th president of the United States from 1977 to 1981. A member of the Democratic Party, he previously served as the 76th governor of Georgia from 19 ...
proclaimed a portion of the Tongass National Forest to be
Misty Fjords National Monument
Misty Fjords National Monument (or Misty Fiords National Monument) is a national monument and wilderness area administered by the U.S. Forest Service as part of the Tongass National Forest. Misty Fiords is about east of Ketchikan, Alaska, along ...
, which included New Eddystone Rock. In 1980 Congress enacted the
Alaska National Interest Lands Conservation Act
The Alaska National Interest Lands Conservation Act (ANILCA) is a United States federal law signed by President Jimmy Carter on December 2, 1980. ANILCA provided varying degrees of special protection to over of land, including national parks, na ...
, which provided wilderness protection to most of the national monument.
The island is currently managed by the
U.S. Forest Service
The United States Forest Service (USFS) is an agency of the U.S. Department of Agriculture that administers the nation's 154 national forests and 20 national grasslands. The Forest Service manages of land. Major divisions of the agency in ...
.
References
{{commons category, New Eddystone Rock (Alaska)
Islands of the Alexander Archipelago
Landforms of Ketchikan Gateway Borough, Alaska