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26-593: The Swinge is the strait between Alderney and Burhou in the Channel Islands . It often sees a furious tidal race (the Alderney Race ), and Braye Harbour which faces it, has a mile-long breakwater to cope with this. The etymology of the Swinge is probably Old Norse , related to Old Icelandic swinnr (swift, rapid) Corbet Rock lies in the Swinge. Corbet Rock is said to have been named after

52-644: A second flood about 225,000 years ago supported by glaciers extending from areas then land such as the Zuiderzee , the Meuse and Rhine were ice-dammed into a lake that broke catastrophically through a high weak barrier (perhaps chalk, or an end-moraine left by the ice sheet). Both floods cut massive flood channels in the dry bed of the English Channel, somewhat like the Channeled Scablands or

78-401: Is typically reserved for much larger, wider features of the marine environment. There are exceptions, with straits being called canals; Pearse Canal , for example. Straits are the converse of isthmuses . That is, while a strait lies between two land masses and connects two large areas of ocean, an isthmus lies between two areas of ocean and connects two large land masses. Some straits have

104-773: The Dover Narrows , is the strait at the narrowest part of the English Channel , marking the boundary between the Channel and the North Sea , and separating Great Britain from continental Europe . The shortest distance across the strait, at approximately 20 miles (32 kilometres), is from the South Foreland , northeast of Dover in the English county of Kent , to Cap Gris Nez , a cape near to Calais in

130-579: The Short Straits (an alternative name for this strait) about 425,000 years ago. A narrow deep channel along the middle of the strait is the remnants of the main (summer) outflow of the northern Ustrom glacial lake (a collect for other then-seasonal rivers, in winter iced up, such as the Thames and Weser) in the last Ice Age . A deposit in East Anglia marks the old preglacial northward course of

156-468: The Suez Canal . Although rivers and canals often provide passage between two large lakes, and these seem to suit the formal definition of strait, they are not usually referred to as such. Rivers and often canals, generally have a directional flow tied to changes in elevation, whereas straits often are free flowing in either direction or switch direction, maintaining the same elevation. The term strait

182-541: The Wabash River in the USA. A further update in 2017 attributed a series of previously described underwater holes in the Channel floor, "100m deep" and in places "several kilometres in diameter", to lake water plunging over a rock ridge causing isolated depressions or plunge pools . The melting ice and rising sea levels submerged Doggerland , the area linking Britain to France, around 6,500–6,200 BCE. The Lobourg strait,

208-623: The 46 m (151 ft) average depth. They help increase diversity in the local species – some of which are endemic to the strait. Moreover, this is a transition zone for the species of the Atlantic Ocean and those of the southern part of the North Sea. This mix of various environments promotes a wide variety of wildlife. The Ridens de Boulogne , a 10–20 m (33–66 ft) deep rocky shoal, partially sand-capped,15 nmi (28 km; 17 mi) west of Boulogne , boasts

234-707: The French département of Pas-de-Calais . Between these points lies the most popular route for cross-channel swimmers . The entire strait is within the territorial waters of France and the United Kingdom, but a right of transit passage under the United Nations Convention on the Law of the Sea allows vessels of other nations to move freely through the strait. On a clear day, it is possible to see

260-458: The Lobourg strait and 20 m (66 ft) at the highest banks. The seabed forms successions of three habitats: The strong tidal currents of the strait at depth slow around its rocky masses as these stimulate countercurrents and deep, calm pockets where many species can find shelter. In these calmer lee zones, the water is clearer than in the rest of the strait; thus algae can grow despite

286-556: The Strait of Dover, rather than taking the longer and more dangerous route around the north of Scotland. The strait is one of the busiest international seaways in the world, used by over 400 commercial vessels daily. This has made traffic safety a critical issue, with HM Coastguard and the Maritime Gendarmerie maintaining a 24-hour watch over the strait and enforcing a strict regime of shipping lanes . In addition to

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312-612: The Urstrom-Thames when it also drained Doggerland . The deep sea floor east of Lincolnshire and East Yorkshire , connecting to the Atlantic via the Pentland Firth in the last glaciation (of over 300,000 years) is a necessary pre-condition for the relatively late cutting through of the Strait to the south. Likewise, a 2007 study concluded that the Strait was formed by erosion caused by two major floods. The first

338-494: The ancient Corbet family of the Channel Islands. The Little Swinge is between Burhou and Les Nannels. The Race is the strait on the other side of Alderney. This Guernsey location article is a stub . You can help Misplaced Pages by expanding it . Straits A strait is a water body connecting two seas or two water basins. While the landform generally constricts the flow, the surface water still flows, for

364-512: The deepest part the strait, runs its 6 km (4 mi)wide slash on a NNE–SSW axis. Nearer to the French coast than to the English, it borders the Varne sandbank (shoals) where it plunges to 68 m (223 ft) and further south, the Ridge bank (shoals) (French name " Colbart " ) with a maximum depth of 62 m (203 ft). The depth of the strait varies between 68 m (223 ft) at

390-941: The highest profusion of maerl in the strait. Thus some 682 km (263 sq mi) of the strait is classified as a Natura 2000 protection zone named Ridens et dunes hydrauliques du Pas de Calais (Ridens and sub-aqueous dunes of the Dover Strait). This includes the sub-aqueous dunes of Varne, Colbart, Vergoyer and Bassurelle, the Ridens de Boulogne , and the Lobourg channel which provides calmer and clearer waters due to its depth reaching 68 m (223 ft). Many crossings other than in conventional vessels have been attempted, including by pedalo , jetpack , bathtub , amphibious vehicle and more commonly by swimming . Since French law bans many of them, unlike English law , most such crossings originate in England. In

416-427: The intensive north-east to south-west traffic, the strait is crossed from north-west to south-east by ferries linking Dover to Calais and Dunkirk . Until 1994 these provided the only route across it except for air transport. The Channel Tunnel now provides an alternative route, crossing beneath the strait at an average depth of 45 m (148 ft) below the seabed. The town of Dover gives its name to one of

442-505: The most part, at the same elevation on both sides and through the strait in both directions. In some straits there may be a dominant directional current through the strait. Most commonly, it is a narrowing channel that lies between two land masses . Some straits are not navigable, for example because they are either too narrow or too shallow, or because of an unnavigable reef or archipelago . Straits are also known to be loci for sediment accumulation. Usually, sand-size deposits occur on both

468-542: The opposite coastline of England from France and vice versa with the naked eye, with the most famous and obvious sight being the White Cliffs of Dover from the French coastline and shoreline buildings on both coastlines, as well as lights on either coastline at night, as in Matthew Arnold 's poem " Dover Beach ". Most maritime traffic between the Atlantic Ocean and the North Sea and Baltic Sea passes through

494-472: The potential to generate significant tidal power using tidal stream turbines . Tides are more predictable than wave power or wind power . The Pentland Firth (a strait) may be capable of generating 10  GW . Cook Strait in New Zealand may be capable of generating 5.6 GW even though the total energy available in the flow is 15 GW. Straits used for international navigation through

520-714: The sea (covering most of the Netherlands) fell during the start of the first of the Pleistocene Ice Ages . The new ice unusually created a dam from Scandinavia to Scotland, and the Rhine, combined with the Thames and drainage from much of north Europe , created a vast lake behind the dam, which eventually spilled over the Weald into the English Channel. This overflow followed by further scouring became recognisably

546-733: The sea areas of the British Shipping Forecast . The formation of strait was through scouring by erosion . It had for many millennia (since the last warm interglacial ) been a land bridge that linked the Weald in Great Britain to the Boulonnais in the Pas de Calais . Though pitted by troughs and rivers, the English Channel was almost mainly land at the height of the last ice age. The predominant geology of both and of

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572-625: The seafloor is chalk . Although somewhat resistant to erosion, erosion of both coasts has created the famous white cliffs of Dover in the UK and the Cap Blanc Nez in France. The Channel Tunnel was bored through solid chalk – compacted remains of sea creatures and marine- deposited , ground up calciferous rock/soil debris. The Rhine (as the Urstrom ) flows northeast into the North Sea as

598-423: The territorial sea between one part of the high seas or an exclusive economic zone and another part of the high seas or an exclusive economic zone are subject to the legal regime of transit passage ( Strait of Gibraltar , Dover Strait , Strait of Hormuz ). The regime of innocent passage applies in straits used for international navigation (1) that connect a part of high seas or an exclusive economic zone with

624-658: The territorial sea of a coastal nation ( Straits of Tiran , Strait of Juan de Fuca , Strait of Baltiysk ) and (2) in straits formed by an island of a state bordering the strait and its mainland if there exists seaward of the island a route through the high seas or through an exclusive economic zone of similar convenience with respect to navigational and hydrographical characteristics ( Strait of Messina , Pentland Firth ). There may be no suspension of innocent passage through such straits. [REDACTED] Media related to Straits at Wikimedia Commons Dover Strait The Strait of Dover or Dover Strait , historically known as

650-574: The two opposite strait exits, forming subaqueous fans or deltas . The terms channel , pass , or passage can be synonymous and used interchangeably with strait , although each is sometimes differentiated with varying senses. In Scotland, firth or Kyle are also sometimes used as synonyms for strait. Many straits are economically important. Straits can be important shipping routes and wars have been fought for control of them. Numerous artificial channels, called canals , have been constructed to connect two oceans or seas over land, such as

676-629: Was about 425,000 years ago, when an ice-dammed lake in the southern North Sea overflowed and broke the Weald- Artois (Boulonnais) chalk range in a catastrophic erosion and flood event. Consequently the ice-age-muted flows from the Thames and Scheldt flowed through the gap into the English Channel/Inlet, but the Meuse and Rhine still flowed without any significant link to the inlet (such as today's IJssel distributary supports). In

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