![Admiralty Chart No 2649 English Channel Western Portion Published 1955](https://upload.wikimedia.org/wikipedia/commons/0/00/Admiralty_Chart_No_2649_English_Channel_Western_Portion_Published_1955.jpg)
Hurd's Deep (or Hurd Deep) is an underwater valley in the
English Channel
The English Channel, "The Sleeve"; nrf, la Maunche, "The Sleeve" (Cotentinais) or ( Jèrriais), (Guernésiais), "The Channel"; br, Mor Breizh, "Sea of Brittany"; cy, Môr Udd, "Lord's Sea"; kw, Mor Bretannek, "British Sea"; nl, Het Kana ...
, northwest of the
Channel Islands
The Channel Islands ( nrf, Îles d'la Manche; french: îles Anglo-Normandes or ''îles de la Manche'') are an archipelago in the English Channel, off the French coast of Normandy. They include two Crown Dependencies: the Bailiwick of Jersey, ...
. Its maximum depth is about 180 m (590 ft; 98 fathoms), making it the deepest point in the English Channel.
Etymology
It is most probable the feature was named after Captain
Thomas Hurd
Thomas Hannaford Hurd ( bapt. 30 January 1747 – 29 April 1823) was an officer of the Royal Navy, who rose to the rank of captain, becoming the second Hydrographer of the Navy, a Superintendent of Chronometers and a Commissioner on the Boar ...
RN (1747–1823), by
Admiral Martin White.
Description
The feature has an approximate length of , a width of between , and a maximum depth of . It terminates abruptly at the western end. Outside of the Deep, the seafloor is typically flat with a depth range of .
It is the deepest point on the English channel.
Late Quaternary origin
The underwater valley system found on the floor of the eastern English Channel formed from a catastrophic flood which was caused by a breaching of a rock dam at the
Strait of Dover
The Strait of Dover or Dover Strait (french: Pas de Calais - ''Strait of Calais''), is the strait at the narrowest part of the English Channel, marking the boundary between the Channel and the North Sea, separating Great Britain from continent ...
, which released a huge
proglacial lake
In geology, a proglacial lake is a lake formed either by the damming action of a moraine during the retreat of a melting glacier, a glacial ice dam, or by meltwater trapped against an ice sheet due to isostatic depression of the crust around the ...
in the southern
North Sea
The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian S ...
basin. The flood scoured the former river systems to form Hurd's Deep in late
Quaternary
The Quaternary ( ) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS). It follows the Neogene Period and spans from 2.58 million years ...
times.
Pleistocene glacial refugium
During the
ice age
An ice age is a long period of reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Earth's climate alternates between ice ages and gree ...
s, when the sea level dropped, most of the
English Channel
The English Channel, "The Sleeve"; nrf, la Maunche, "The Sleeve" (Cotentinais) or ( Jèrriais), (Guernésiais), "The Channel"; br, Mor Breizh, "Sea of Brittany"; cy, Môr Udd, "Lord's Sea"; kw, Mor Bretannek, "British Sea"; nl, Het Kana ...
was dry land. Hurd's Deep likely remained as a sea. During the
Pleistocene
The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fina ...
it is thought to have been a
glacial refugium A glacial refugium (''plural refugia'') is a geographic region which made possible the survival of flora and fauna in times of ice ages and allowed for post-glacial re-colonization. Different types of glacial refugia can be distinguished, namely nun ...
.
Seabed
Dumping
Following the First World War, Hurd's Deep was used by the British Government as a
dumping ground for both chemical and conventional munitions.
was scuttled there in 1921. Following the Second World War, it was used to dump military equipment, munitions and weaponry left behind by the ousted German invaders of the Channel Islands.
Routine dumping of British munitions carried on until 1974.
Between 1946 and 1973 the area was also used for the
dumping of low and intermediate level
radioactive waste
Radioactive waste is a type of hazardous waste that contains radioactive material. Radioactive waste is a result of many activities, including nuclear medicine, nuclear research, nuclear power generation, rare-earth mining, and nuclear weapons r ...
s. 28,500 barrels of waste – including plutonium, which has a half-life of 24,100 years – were disposed of into the Deep during this period.
Shipwrecks
The British submarine sank in Hurd's Deep in 1951 with the loss of 75 lives.
In popular culture
In
Harry Collingwood's
science fiction
Science fiction (sometimes shortened to Sci-Fi or SF) is a genre of speculative fiction which typically deals with imaginative and futuristic concepts such as advanced science and technology, space exploration, time travel, parallel unive ...
stories about the ''Flying-Fish'' airship-submarine, the ''Flying-Fish'' is hidden in Hurd's Deep between adventures.
Notes, references and sources
Notes
References
Sources
*
*
English Channel
Radioactive waste repositories
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