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Anton Dohrn Seamount
The Anton Dohrn Seamount is a guyot in the Rockall Trough in the northeast Atlantic. It is high and is topped with pinnacles, one of which reaches a depth of . Away from the flat top upon which the pinnacles rest, the slopes fall off steeply into the Rockall Trough and a moat in the sediment that surrounds the seamount. It appears to be a volcano formed by basaltic lava and tuff. It formed during the Cretaceous and Paleogene and was proposed to be a source for bentonite layers across the British Isles. After the Cretaceous, subsidence and erosion lowered its top until it sank below sea level. The seamount was discovered in 1958. Anton Dohrn Seamount hosts a diverse ecosystem characterized by reefs formed by cold water corals, sponges and xenophyophorans, which themselves host a number of animals. It has been affected by human fishing operations, however. Name and research history Anton Dohrn Seamount is also known as Anton Dohrn Kuppe, a name used by German charts, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the "Old World" of Africa, Europe and Asia from the "New World" of the Americas in the European perception of the World. The Atlantic Ocean occupies an elongated, S-shaped basin extending longitudinally between Europe and Africa to the east, and North and South America to the west. As one component of the interconnected World Ocean, it is connected in the north to the Arctic Ocean, to the Pacific Ocean in the southwest, the Indian Ocean in the southeast, and the Southern Ocean in the south (other definitions describe the Atlantic as extending southward to Antarctica). The Atlantic Ocean is divided in two parts, by the Equatorial Counter Current, with the North(ern) Atlantic Ocean and the South(ern) Atlantic Ocean split at about 8°N. Scientific explorations of the Atlant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sponge
Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate through them, consisting of jelly-like mesohyl sandwiched between two thin layers of cells. Sponges have unspecialized cells that can transform into other types and that often migrate between the main cell layers and the mesohyl in the process. Sponges do not have nervous, digestive or circulatory systems. Instead, most rely on maintaining a constant water flow through their bodies to obtain food and oxygen and to remove wastes. Sponges were first to branch off the evolutionary tree from the last common ancestor of all animals, making them the sister group of all other animals. Etymology The term ''sponge'' derives from the Ancient Greek word ( 'sponge'). Overview Sponges are similar to other animals in that they are multicellular, he ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ridge
A ridge or a mountain ridge is a geographical feature consisting of a chain of mountains or hills that form a continuous elevated crest for an extended distance. The sides of the ridge slope away from the narrow top on either side. The lines along the crest formed by the highest points, with the terrain dropping down on either side, are called the ridgelines. Ridges are usually termed hills or mountains as well, depending on size. Smaller ridges, especially those leaving a larger ridge, are often referred to as spurs. Types There are several main types of ridges: ;Dendritic ridge: In typical dissected plateau terrain, the stream drainage valleys will leave intervening ridges. These are by far the most common ridges. These ridges usually represent slightly more erosion resistant rock, but not always – they often remain because there were more joints where the valleys formed or other chance occurrences. This type of ridge is generally somewhat random in orientation, often ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cliff
In geography and geology, a cliff is an area of rock which has a general angle defined by the vertical, or nearly vertical. Cliffs are formed by the processes of weathering and erosion, with the effect of gravity. Cliffs are common on coasts, in mountainous areas, escarpments and along rivers. Cliffs are usually composed of rock that is resistant to weathering and erosion. The sedimentary rocks that are most likely to form cliffs include sandstone, limestone, chalk, and dolomite. Igneous rocks such as granite and basalt also often form cliffs. An escarpment (or scarp) is a type of cliff formed by the movement of a geologic fault, a landslide, or sometimes by rock slides or falling rocks which change the differential erosion of the rock layers. Most cliffs have some form of scree slope at their base. In arid areas or under high cliffs, they are generally exposed jumbles of fallen rock. In areas of higher moisture, a soil slope may obscure the talus. Many cliffs also fea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gravel
Gravel is a loose aggregation of rock fragments. Gravel occurs naturally throughout the world as a result of sedimentary and erosive geologic processes; it is also produced in large quantities commercially as crushed stone. Gravel is classified by particle size range and includes size classes from granule- to boulder-sized fragments. In the Udden-Wentworth scale gravel is categorized into granular gravel () and pebble gravel (). ISO 14688 grades gravels as fine, medium, and coarse, with ranges 2–6.3 mm to 20–63 mm. One cubic metre of gravel typically weighs about 1,800 kg (or a cubic yard weighs about 3,000 lb). Gravel is an important commercial product, with a number of applications. Almost half of all gravel production is used as aggregate for concrete. Much of the rest is used for road construction, either in the road base or as the road surface (with or without asphalt or other binders.) Naturally occurring porous gravel deposits have a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hebrides Terrace Seamount
Hebrides Terrace Seamount is a seamount in the Atlantic Ocean, west-southwest from the Hebrides, Scotland. It formed through volcanism during the early Cenozoic in the Rockall Trough 60 million to 67 million years ago and afterwards sank below sea level. Presently, it is a flat-topped underwater mountain that rises to about 980 metres (3,220 ft) depth. "Coral gardens" that host a number of animals are found on its slopes. Geography and geomorphology The seamount lies in the southern Rockall Trough, at the foot of the Scottish continental slope and west-southwest of Barra Head, Hebrides. It is the smallest of three seamounts in the Rockall Trough; the other two are Anton Dohrn Seamount and Rosemary Bank both north of Hebrides Terrace Seamount, and farther west is the Rockall Bank. It straddles the political border between the United Kingdom and Ireland. The Hebrides Terrace Seamount is a volcanic guyot, a seamount with a flat top and steep slopes, that rises to a depth of abo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rosemary Bank
Rosemary Bank is a seamount approximately west of Scotland, located in the Rockall Trough, in the northeast Atlantic. It was discovered in 1930 by the survey vessel HMS ''Rosemary'', from which it takes its name. It is one of only three seamounts known in Scottish waters. Rosemary Bank hosts a range of important habitats including deep sea sponge aggregations and cold water coral. Many species of fish, including orange roughy, blue ling, leafscale gulper shark The leafscale gulper shark (''Centrophorus squamosus'') is a dogfish of the family Centrophoridae. ''C. squamosus'' is reported to have a lifespan of approximately 70 years, based on otolith ring counts. It was the first described species in ... and Portuguese dogfish are also found here. In 2014 the bank was declared a Nature Conservation Marine Protected Area (NCMPA) in order to protect the sponge aggregations, and the cenozoic marine geomorphology of the seabed. The designation was withdrawn in 2020, when ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rockall
Rockall () is an uninhabitable granite islet situated in the North Atlantic Ocean. The United Kingdom claims that Rockall lies within its exclusive economic zone (EEZ) and is part of its territory, but this claim is not recognised by Ireland. It and the nearby skerries of Hasselwood Rock and Helen's Reef are the only emergent parts of the Rockall Plateau. The rock was formed by magmatism as part of the North Atlantic Igneous Province during the Paleogene. Rockall's approximate distances from the closest islands in each direction are as follows: It is west of Soay, Scotland; northwest of Tory Island, Ireland; and south of Iceland. The nearest permanently inhabited place is North Uist, an island in the Outer Hebrides of Scotland, to the east. The United Kingdom claimed Rockall in 1955 and incorporated it as a part of Scotland in 1972. The UK does not make a claim to extended EEZ based on Rockall, as it has ratified the United Nations Convention on the Law of the Sea (UNCLOS ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hebrides
The Hebrides (; gd, Innse Gall, ; non, Suðreyjar, "southern isles") are an archipelago off the west coast of the Scottish mainland. The islands fall into two main groups, based on their proximity to the mainland: the Inner and Outer Hebrides. These islands have a long history of occupation (dating back to the Mesolithic period), and the culture of the inhabitants has been successively influenced by the cultures of Celtic-speaking, Norse-speaking, and English-speaking peoples. This diversity is reflected in the various names given to the islands, which are derived from the different languages that have been spoken there at various points in their history. The Hebrides are where much of Scottish Gaelic literature and Gaelic music has historically originated. Today, the economy of the islands is dependent on crofting, fishing, tourism, the oil industry, and renewable energy. The Hebrides have less biodiversity than mainland Scotland, but a significant number of seals an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
St Kilda, Scotland
St Kilda ( gd, Hiort) is an isolated archipelago situated west-northwest of North Uist in the North Atlantic Ocean. It contains the westernmost islands of the Outer Hebrides of Scotland. The largest island is Hirta, whose sea cliffs are the highest in the United Kingdom; three other islands ( Dùn, Soay and Boreray) were also used for grazing and seabird hunting. The islands are administratively a part of the Comhairle nan Eilean Siar local authority area. The origin of the name ''St Kilda'' is a matter of conjecture. The islands' human heritage includes numerous unique architectural features from the historic and prehistoric periods, although the earliest written records of island life date from the Late Middle Ages. The medieval village on Hirta was rebuilt in the 19th century, but illnesses brought by increased external contacts through tourism, and the upheaval of the First World War contributed to the island's evacuation in 1930. The story of St Kilda has attracted artis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scotland
Scotland (, ) is a country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a border with England to the southeast and is otherwise surrounded by the Atlantic Ocean to the north and west, the North Sea to the northeast and east, and the Irish Sea to the south. It also contains more than 790 islands, principally in the archipelagos of the Hebrides and the Northern Isles. Most of the population, including the capital Edinburgh, is concentrated in the Central Belt—the plain between the Scottish Highlands and the Southern Uplands—in the Scottish Lowlands. Scotland is divided into 32 administrative subdivisions or local authorities, known as council areas. Glasgow City is the largest council area in terms of population, with Highland being the largest in terms of area. Limited self-governing power, covering matters such as education, social services and roads and transportation, is devolved from the Scott ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
