Wiktionary
n. A submarine cave or sinkhole, a roughly circular, steep-walled depression that is typically anoxic below a certain depth.
Wikipedia
Blue Hole is a diving location on east Sinai, a few kilometres north of Dahab, Egypt on the coast of the Red Sea.
The Blue Hole is a submarine sinkhole, around 94 m (300 feet) deep. There is a shallow opening around 6 m deep, known as "the saddle", opening out to the sea, and a 26 m long tunnel, known as "the arch", whose top is at a depth of 56 m (184 feet). The hole and the surrounding area have an abundance of coral and reef fish.
There is a local legend that the Blue Hole is cursed by the ghost of a girl who drowned herself there to escape from an arranged marriage.
The Blue Hole is a hot spot for freediving because of the depth directly accessible from shore and the lack of current.
A blue hole is a large marine cavern or sinkhole, which is open to the surface and has developed in a bank or island composed of a carbonate bedrock ( limestone or coral reef). Blue holes typically contain tidally-influenced water of fresh, marine, or mixed chemistry. They extend below sea level for most of their depth and may provide access to submerged cave passages. Well-known examples can be found in South China Sea ( Dragon Hole), Belize, the Bahamas, Guam, Australia (in the Great Barrier Reef), and Egypt (in the Red Sea).
Blue holes are distinguished from cenotes in that the latter are inland voids usually containing fresh groundwater rather than seawater.
The Blue Hole is located in the Pinelands of Monroe Township, Gloucester County, New Jersey and Winslow Township, Camden County, New Jersey. It is a clear blue body of water situated in the middle of a dense forest, with many similar such lakes in its immediate vicinity. The water has warm and cold spots, averaging 58 to 60 degrees Fahrenheit. The color is very unusual, as most lakes and ponds in the area are brownish due to large deposits of bog iron and the presence of tannic acid. The Blue Hole is circular and about across. In the 1930s, the Blue Hole was a popular party and swimming spot. A wooden footbridge over the Great Egg Harbor River that once made the Hole easily accessible was wiped out by a storm in the 1960s; now it can only be reached on foot.
A number of legends exist: that it is bottomless with powerful currents, that the water is freezing cold year-round, and that the Jersey Devil is active in the area.
After people became afraid of it, the blue hole was largely abandoned. Perhaps farmers and families in the area warned children against going to the Blue Hole because the Jersey Devil lived there, and it would hurt or steal them. Locals still go to the area and use it as a party spot. There are many other 'blue holes' in the immediate vicinity, as well as quicksand and other seasonal ponds and lakes that form from springs seeping from high water table levels.
At its deepest point, the Blue Hole is 9.9 feet deep. The bottom appears to consist of mud rather than sand. Swimming and diving in the Blue Hole are both illegal.
The term blue hole usually refers to a submarine cave or sinkhole, but may also refer to:
is a science fiction manga series by Yukinobu Hoshino involving dinosaurs living in the present. Its title in France is Le Trou Bleu. It was serialized in Mister Magazine from 1991 to 1992 with two tankōbon published.
The Blue Hole is a fresh water pond located in Castalia, Erie County, Ohio, in the United States. From the 1920s to 1990 the Blue Hole was a tourist site, attracting 165,000 visitors annually at the height of its popularity, partly because of its location on State Route 269, about southwest of the Cedar Point amusement park in Sandusky, Ohio.
The Blue Hole captured the public’s interest because of its size, about in diameter, clarity, vibrant blue hue, and enigmatic "bottomless" appearance. Contrary to prevalent belief, the depth of the Blue Hole is not unknown, but has been sounded and found to be about deep. Water temperature is about throughout the year. Floods and droughts have no effect on temperature or water level. The Blue Hole is fed by a passing underground stream which discharges of water daily into Sandusky Bay to the north, feeding into Lake Erie. The water contains lime, soda, magnesia and iron, and because the Blue Hole is anoxic, it cannot naturally sustain fish. The surrounding terrain is developed on limestone bedrock and exhibits karst topography due to dissolution of the limestone by ground water, creating water-filled sinkholes. The Blue Hole was known to American Indians and was first recorded in history in 1761. Several similar blue holes are known to local residents. The Blue Hole that once was a tourist attraction is now off limits to the public. It is located on the grounds of Castalia Trout Club. It is to be distinguished from another hole similar in size and eerie bluish-green color. This latter hole is owned by the Castalia State Fish Hatchery operated by the Ohio Department of Natural Resources, Division of Wildlife and is open for public viewing.
The Blue Hole is an attraction on the island of Big Pine Key in the Florida Keys. It is an abandoned rock quarry that was used for nearby road fills and Henry Flagler's Overseas Railroad. The water it contains is mostly fresh and is used by various wildlife in the area, such as birds, snakes, alligators, key deer and green iguanas. It is part of the National Key Deer Refuge.
The Blue Hole of Santa Rosa is a circular, bell-shaped pool east of Santa Rosa, New Mexico that is one of the most popular dive destinations in the US for SCUBA diving and training. The Blue Hole is an artesian well that was once used as a fish hatchery. It is a clear blue body of water with a constant temperature and constant inflow of . While the surface is only in diameter, it expands to a diameter of at the bottom.
Since Santa Rosa, New Mexico is at an elevation of , it is necessary for divers to use high-altitude dive tables to compute the dive profile and decompression stops when diving in the Blue Hole.
The pool is open for public use with On-Duty Lifeguards.
Tanks may be filled or rented as well as some equipment at a private dive shop located at the site.
On March 26, 2016 43 year old California diver Shane Thompson a Navy veteran from the ADM Exploration Foundation was exploring passageways and became trapped and accidentally drowned.
Usage examples of "blue hole".
Hands linked, Finnbogg at their heels, they raced toward the blue hole Sidi Bombay had said would lead them to the next level of the Dungeon.
The looming planet was dim, at first just a faintly blue hole against the stars, then gradually, as her eyes dark-adapted, filling with misty detail, becoming a ball of subtle blue and violet, visibly structured.
There was a neat blue hole surrounded by a corona of powder burns in the center of his forehead.
He saw a blue hole ahead, where the road ended on the crest of a ridge.