Dean's Blue Hole
Encyclopedia
Dean's Blue Hole is the world's deepest known blue hole
with seawater. It plunges 202 metres (662.7 ft) in a bay west of Clarence Town
on Long Island
, Bahamas.
In April 2010, William Trubridge
broke a free-diving
world record in the blue hole reaching a depth of 92 metres (301.8 ft) without the use of fins (Constant Weight Without Fins
). On December 14, 2010, he swam to a depth of 101 metres on a single breath using only his hands and feet for propulsion, while many divers use weights to quicken their descent or inflatable bags to bring them to the surface quickly.
is a term which often is given to sinkhole
s filled with water, with the entrance below the water level. They can be formed in different karst
processes, for example, by the rainwater soaking through fractures of limestone bedrock onto the watertable. Sea level here has changed: for example, during the glacial age during the Pleistocene
epoch (ice age
), some 15,000 years ago, sea level was considerably lower. The maximum depth of most other known blue holes and sinkholes is 110 metres (360.9 ft), which makes the 202 metres (662.7 ft) depth of Dean's Blue Hole quite exceptional.
Dean's Blue Hole is roughly circular at the surface, with a diameter ranging from 25 to 35 m (82 to 114.8 ft). After descending 20 metres (65.6 ft), the hole widens considerably into a cavern with a diameter of 100 metres (328.1 ft).
Some water-filled sinkholes are deeper than Dean's Blue Hole, Zacatón
in Mexico (335 metres (1,099.1 ft)) and Pozzo del Merro in Italy (392 metres (1,286.1 ft)) among them. Dean's Blue Hole though is the deepest known sinkhole with entrance below the sea level.
Blue hole
A blue hole is a cave or underwater sinkhole. They are also called vertical caves. There are many different blue holes located around the world, typically in low-lying coastal regions...
with seawater. It plunges 202 metres (662.7 ft) in a bay west of Clarence Town
Clarence Town
Clarence Town is a town in the Bahamas. It is located on Long Island.Clarence Town is the capital of Long Island and has a population of approximately 350 people. It has a marina, two restaurants as well as the government dock where the mail boat docks on a weekly basis...
on Long Island
Long Island, Bahamas
Long Island is an island in the Bahamas that is split by the Tropic of Cancer. Its capital is Clarence Town. Long Island is one of the Districts of the Bahamas and is known as the most scenic island in the Bahamas. The population is roughly 4,000 inhabitants.-Geography:Long Island is about 130...
, Bahamas.
History
The full depth of the cave was reached by Jim King in 1992.In April 2010, William Trubridge
William Trubridge
William Trubridge is a world champion and double world record holding free-diver from New Zealand.Trubridge currently holds the world record in the Free Immersion and the Constant Weight without fins disciplines, and is the first human ever to break the 100m barrier unassisted.World Records:•...
broke a free-diving
Free-diving
Freediving is any of various aquatic activities that share the practice of breath-hold underwater diving. Examples include breathhold spear fishing, freedive photography, apnea competitions and, to a degree, snorkeling...
world record in the blue hole reaching a depth of 92 metres (301.8 ft) without the use of fins (Constant Weight Without Fins
Constant Weight without fins
Constant Weight Without Fins is an free-diving discipline in which the free-diver descends and ascends by swimming without the use of fins or without pulling on the rope or changing his ballast; only a single hold of the rope to stop the descent and to start the ascent is allowed...
). On December 14, 2010, he swam to a depth of 101 metres on a single breath using only his hands and feet for propulsion, while many divers use weights to quicken their descent or inflatable bags to bring them to the surface quickly.
Formation
Blue holeBlue hole
A blue hole is a cave or underwater sinkhole. They are also called vertical caves. There are many different blue holes located around the world, typically in low-lying coastal regions...
is a term which often is given to sinkhole
Sinkhole
A sinkhole, also known as a sink, shake hole, swallow hole, swallet, doline or cenote, is a natural depression or hole in the Earth's surface caused by karst processes — the chemical dissolution of carbonate rocks or suffosion processes for example in sandstone...
s filled with water, with the entrance below the water level. They can be formed in different karst
KARST
Kilometer-square Area Radio Synthesis Telescope is a Chinese telescope project to which FAST is a forerunner. KARST is a set of large spherical reflectors on karst landforms, which are bowlshaped limestone sinkholes named after the Kras region in Slovenia and Northern Italy. It will consist of...
processes, for example, by the rainwater soaking through fractures of limestone bedrock onto the watertable. Sea level here has changed: for example, during the glacial age during the Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....
epoch (ice age
Ice age
An ice age or, more precisely, glacial age, is a generic geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in the presence or expansion of continental ice sheets, polar ice sheets and alpine glaciers...
), some 15,000 years ago, sea level was considerably lower. The maximum depth of most other known blue holes and sinkholes is 110 metres (360.9 ft), which makes the 202 metres (662.7 ft) depth of Dean's Blue Hole quite exceptional.
Dean's Blue Hole is roughly circular at the surface, with a diameter ranging from 25 to 35 m (82 to 114.8 ft). After descending 20 metres (65.6 ft), the hole widens considerably into a cavern with a diameter of 100 metres (328.1 ft).
Some water-filled sinkholes are deeper than Dean's Blue Hole, Zacatón
Zacatón
Zacatón is thermal water filled sinkhole belonging to Zacatón system - group of unusual karst features located in Aldama Municipality in the northeastern state of Tamaulipas, Mexico. It is the deepest known water-filled sinkhole in the world with a total depth of...
in Mexico (335 metres (1,099.1 ft)) and Pozzo del Merro in Italy (392 metres (1,286.1 ft)) among them. Dean's Blue Hole though is the deepest known sinkhole with entrance below the sea level.
External links
- Dean's Blue Hole entry and exact location on BlooseeBlooseeBlooSee is a social network and an ocean web mapping site where sailors, divers, surfers and other sea lovers geotag and share information and knowledge about the oceans. BlooSee is built in Python and uses the Google Maps API.BlooSee is owned by BlooSee, Inc...
- The Blue Holes Foundation
- Vertical Blue
- Underwater base jump into blue hole (Guillame Nery, Julie Gautier)