The continent of Australia, sometimes known in technical contexts by the names Sahul, Australinea, or Meganesia to distinguish it from the country of Australia, consists of the landmasses which sit on Australias continental plate. This includes mainland Australia, Tasmania, and the island of New Guinea, which comprises Papua New Guinea and Indonesias Western New Guinea. Situated in the geographical region of Oceania, it is the smallest of the seven traditional continents in the English conception. The continent includes a continental shelf overlain by shallow seas which divide it into seve ...
Atlantica is an ancient continent that formed during the Proterozoic about 2.000 million years ago from various 2 Ga cratons located in what is now West Africa and eastern South America. The name, introduced by Rogers 1996, was chosen because the continent opened up to form the South Atlantic Ocean.
Zealandia, also known as the New Zealand continent or Tasmantis, is an almost entirely submerged mass of continental crust that subsided after breaking away from Gondwanaland 83–79 million years ago. It has variously been described as a continental fragment, a microcontinent, a submerged continent, and a continent. The name and concept for Zealandia was proposed by Bruce Luyendyk in 1995. The land mass may have been completely submerged by about 23 million years ago, and most of it 93% remains submerged beneath the Pacific Ocean. With a total area of 4.920.000 km 2 1.900.000 sq mi, it is t ...
Nena, an acronym for Northern Europe–North America, was the Early Proterozoic amalgamation of Baltica and Laurentia into a single "cratonic landmass", a name first proposed in 1990. Since then several similar Proterozoic supercontinents have been proposed, including Nuna and Arctica, that include other Archaean cratons, such as Siberia and East Antarctica. In the original concept Nena formed c. 1.900 million years ago in the Penokean, Makkovikan, Ketilidian, and Svecofennian orogenies. However, because Nena excludes several known Archaean cratons, including those in India and Australia, it ...
Ur is a proposed supercontinent that formed in the Archean 3.100 million years ago. In Rogers reconstruction, Ur is half a billion years older than Arctica and, in the early period of its existence, it was probably the only continent on Earth, and as such can be considered a supercontinent, though it was probably smaller than present-day Australia. In more recent works geologists often refer to both Ur and other proposed Archaean continental assemblages as supercratons. Ur can, nevertheless, be half a billion years younger than Vaalbara, but the concepts of these two early cratonic assembl ...
A continent is a large landmass. The Continent is used by those on the periphery of Europe to refer the mainland. Continent or the continent may also refer to:
In geology, a supercontinent is the assembly of most or all of Earths continental blocks or cratons to form a single large landmass. However, many earth scientists use a different definition: "a clustering of nearly all continents", which leaves room for interpretation and is easier to apply to Precambrian times. Supercontinents have assembled and dispersed multiple times in the geologic past see table. According to the modern definitions, a supercontinent does not exist today. The supercontinent Pangaea is the collective name describing all of the continental landmasses when they were mos ...
The supercontinent cycle is the quasi-periodic aggregation and dispersal of Earths continental crust. There are varying opinions as to whether the amount of continental crust is increasing, decreasing, or staying about the same, but it is agreed that the Earths crust is constantly being reconfigured. One complete supercontinent cycle is said to take 300 to 500 million years. Continental collision makes fewer and larger continents while rifting makes more and smaller continents.
A paleocontinent or palaeocontinent is a distinct area of continental crust that existed as a major landmass in the geological past. There have been many different landmasses throughout Earths time. They range in sizes, some are just a collection of small microcontinents while others are large conglomerates of crust. As time progresses and sea levels rise and fall more crust can be exposed making way for larger landmasses. The continents of the past shaped the evolution of organisms on Earth and contributed to the climate of the globe as well. As land masses break apart, species are separa ...
The archaeology of the Americas is the study of the archaeology of North America, Central America, South America and the Caribbean. This includes the study of pre-historic/Pre-Columbian and historic indigenous American peoples, as well as historical archaeology of more recent eras.
Afro-Eurasia is a landmass comprising the continents of Africa and Eurasia. The terms are portmanteaus of the names of its constituent parts. Its mainland is the largest contiguous landmass on Earth. Afro-Eurasia encompasses 84.980.532 square kilometres 32.811.167 sq mi, a little over half the worlds land area, and has a population of approximately 6 billion people, roughly 86% of the world population.
Eurasia is the largest continental area on Earth, comprising all of Europe and Asia. Located primarily in the Northern and Eastern Hemispheres, it is bordered by the Atlantic Ocean to the west, the Pacific Ocean to the east, the Arctic Ocean to the north, and by Africa, the Mediterranean Sea, and the Indian Ocean to the south. The division between Europe and Asia as two different continents is a historical social construct, with no clear physical separation between them; thus, in some parts of the world, Eurasia is recognized as the largest of the six, five, or even four continents on Eart ...
Laurasia, a portmanteau for Laurentia and Asia, was the more northern of two minor supercontinents that formed part of the Pangaea supercontinent from c. 425 million years ago to 200 Mya. It separated from Gondwana 215 to 175 Mya during the breakup of Pangaea, drifting farther north after the split and finally broke apart with the opening of the North Atlantic Ocean c. 56 Mya. Laurentia, Avalonia, and Baltica, and a series of smaller terranes, collided in the Caledonian orogeny c. 400 Ma to form Laurussia. Laurussia then collided with Gondwana to form Pangaea. Kazakhstania and Siberia was ...
Asia) is Earths largest and most populous continent, located primarily in the Eastern and Northern Hemispheres. It shares the continental landmass of Eurasia with the continent of Europe and the continental landmass of Afro-Eurasia with both Europe and Africa. Asia covers an area of 44.579.000 square kilometres, about 30% of Earths total land area and 8.7% of the Earths total surface area. The continent, which has long been home to the majority of the human population, was the site of many of the first civilizations. Asia is notable for not only its overall large size and population, but a ...
Africa is the worlds second-largest and second-most populous continent, after Asia. At about 30.3 million km 2 including adjacent islands, it covers 6% of Earths total surface area and 20% of its land area. With 1.3 billion people as of 2018, it accounts for about 16% of the worlds human population. The continent is surrounded by the Mediterranean Sea to the north, the Isthmus of Suez and the Red Sea to the northeast, the Indian Ocean to the southeast and the Atlantic Ocean to the west. The continent includes Madagascar and various archipelagos. It contains 54 fully recognised sovereign st ...
The Americas comprise the totality of the continents of North and South America. Together, they make up most of the land in Earths western hemisphere and comprise the New World. Along with their associated islands, they cover 8% of Earths total surface area and 28.4% of its land area. The topography is dominated by the American Cordillera, a long chain of mountains that runs the length of the west coast. The flatter eastern side of the Americas is dominated by large river basins, such as the Amazon, St. Lawrence River / Great Lakes basin, Mississippi, and La Plata. Since the Americas exten ...
Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It comprises the westernmost part of Eurasia and is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east. The eastern border comprises a long and mixed line of mountain ranges and waterways that would normally define a subcontinent. However, Europe is generally accorded the status of a full continent because of its great physical size and the weight of history and tradition. It is the 6th largest continent in ...
The Antarctic is a polar region around the Earths South Pole, opposite the Arctic region around the North Pole. The Antarctic comprises the continent of Antarctica, the Kerguelen Plateau and other island territories located on the Antarctic Plate or south of the Antarctic Convergence. The Antarctic region includes the ice shelves, waters, and all the island territories in the Southern Ocean situated south of the Antarctic Convergence, a zone approximately 32 to 48 km wide varying in latitude seasonally. The region covers some 20 percent of the Southern Hemisphere, of which 5.5 percent is t ...
A continent is one of several very large landmasses. Generally identified by convention rather than any strict criteria, up to seven regions are commonly regarded as continents geopolitically. Ordered from largest in area to smallest, these seven regions are: Asia, Africa, North America, South America, Antarctica, Europe, and Australia. Schemes with fewer continents may merge some of these, for example some systems include Eurasia or America as single continents.
Geologically, the continents correspond to areas of continental crust that are found on the continental plates, but include continental fragments such as Madagascar that are not counted among the geopolitical continents. Some geological continents are largely covered with water, such as Zealandia see submerged continents below. Continental crust is only known to exist on Earth.
Oceanic islands are frequently grouped with a neighbouring continent to divide all the worlds land into geopolitical regions. Under this scheme, most of the island countries and territories in the Pacific Ocean are grouped together with the continent of Australia to form a geopolitical region called Oceania.
1. Definitions and application
By convention, "continents are understood to be large, continuous, discrete masses of land, ideally separated by expanses of water." In modern schemes with five or more recognised continents, at least one pair of continents is joined by land in some way. The criterion "large" leads to arbitrary classification: Greenland, with a surface area of 2.166.086 square kilometres 836.330 sq mi is considered the worlds largest island, while Australia, at 7.617.930 square kilometres 2.941.300 sq mi is deemed the smallest continent.
Earths major landmasses all have coasts on a single, continuous World Ocean, which is divided into a number of principal oceanic components by the continents and various geographic criteria.
1.1. Definitions and application Extent
The most restricted meaning of continent is that of a continuous area of land or mainland, with the coastline and any land boundaries forming the edge of the continent. In this sense the term continental Europe sometimes referred to in Britain as "the Continent" is used to refer to mainland Europe, excluding islands such as Great Britain, Ireland, Malta and Iceland, and the term continent of Australia may refer to the mainland of Australia, excluding Tasmania and New Guinea. Similarly, the continental United States refers to the 48 contiguous states and the District of Columbia in central North America and may include Alaska in the northwest of the continent the two being separated by Canada, while excluding Hawaii, Puerto Rico, and Guam in the oceans.
From the perspective of geology or physical geography, continent may be extended beyond the confines of continuous dry land to include the shallow, submerged adjacent area the continental shelf and the islands on the shelf continental islands, as they are structurally part of the continent.
From this perspective, the edge of the continental shelf is the true edge of the continent, as shorelines vary with changes in sea level. In this sense the islands of Great Britain and Ireland are part of Europe, while Australia and the island of New Guinea together form a continent.
As a cultural construct, the concept of a continent may go beyond the continental shelf to include oceanic islands and continental fragments. In this way, Iceland is considered part of Europe and Madagascar part of Africa. Extrapolating the concept to its extreme, some geographers group the Australian continental plate with other islands in the Pacific into one "quasi-continent" called Oceania. This divides the entire land surface of Earth into continents or quasi-continents.
1.2. Definitions and application Separation
The ideal criterion that each continent is a discrete landmass is commonly relaxed due to historical conventions. Of the seven most globally recognized continents, only Antarctica and Australia are completely separated from other continents by the ocean. Several continents are defined not as absolutely distinct bodies but as more or less discrete masses of land". Asia and Africa are joined by the Isthmus of Suez, and North and South America by the Isthmus of Panama. In both cases, there is no complete separation of these landmasses by water. Both these isthmuses are very narrow compared to the bulk of the landmasses they unite.
North America and South America are treated as separate continents in the seven-continent model. However, they may also be viewed as a single continent known as America or the Americas. This viewpoint was common in the United States until World War II, and remains prevalent in some Asian six-continent models. This remains the more common vision in Latin American countries, Spain, Portugal, France, Italy, Germany, Greece and Hungary, where they are taught as a single continent.
The criterion of a discrete landmass is completely disregarded if the continuous landmass of Eurasia is classified as two separate continents: Europe and Asia. Physiographically, Europe and South Asia are peninsulas of the Eurasian landmass. However, Europe is widely considered a continent with its comparatively large land area of 10.180.000 square kilometres 3.930.000 sq mi, while South Asia, with less than half that area, is considered a subcontinent. The alternative view - in geology and geography - that Eurasia is a single continent results in a six-continent view of the world. Some view separation of Eurasia into Asia and Europe as a residue of Eurocentrism: "In physical, cultural and historical diversity, China and India are comparable to the entire European landmass, not to a single European country." However, for historical and cultural reasons, the view of Europe as a separate continent continues in several categorizations.
If continents are defined strictly as discrete landmasses, embracing all the contiguous land of a body, then Africa, Asia, and Europe form a single continent which may be referred to as Afro-Eurasia. This produces a four-continent model consisting of Afro-Eurasia, America, Antarctica and Australia.
When sea levels were lower during the Pleistocene ice ages, greater areas of continental shelf were exposed as dry land, forming land bridges. At those times Australia–New Guinea was a single, continuous continent. Likewise, the Americas and Afro-Eurasia were joined by the Bering land bridge. Other islands such as Great Britain were joined to the mainlands of their continents. At that time there were just three discrete continents: Afro-Eurasia-America, Antarctica, and Australia-New Guinea.
1.3. Definitions and application Number
There are several ways of distinguishing the continents:
- The six-continent combined-America model is often used in Latin America, Greece, and countries that speak Romance languages.
- The seven-continent model is usually taught in most English-speaking countries including the United Kingdom and Australia, and also in China, India, Pakistan, the Philippines, and parts of Western Europe.
- A five-continent model is obtained from the combined-America model by excluding Antarctica as uninhabited. This is used, for example in the United Nations and in the Olympic Charter in its description of the Olympic flag.
- The six-continent combined-Eurasia model is mostly used in Russia, Eastern Europe, and Japan.
The term Oceania refers to a group of island countries and territories in the Pacific Ocean, together with the continent of Australia. Pacific islands with ties to other continents such as Japan, Hawaii or Easter Island are usually grouped with those continents rather than Oceania. This term is used in several different continental models instead of Australia.
2. Area and population
The following table summarizes the area and population of the continental regions used by the United Nations. These regions differ from the physical continents in various ways that are explained in the notes.
The total land area of all continents is 148.647.000 square kilometres 57.393.000 sq mi, or 29.1% of earths surface 510.065.600 km 2 or 196.937.400 sq mi.
3.1. Other divisions Supercontinents
Aside from the conventionally known continents, the scope and meaning of the term continent varies. Supercontinents, largely in evidence earlier in the geological record, are landmasses that comprise more than one craton or continental core. These have included Laurasia, Gondwana, Vaalbara, Kenorland, Columbia, Rodinia, Pangaea. Over time, these supercontinents broke apart into large land masses which caused the formation of the present continents.
3.2. Other divisions Subcontinents
Certain parts of continents are recognized as subcontinents, especially the large peninsulas separated from the main continental landmass by geographical features. The most notable examples are the Indian subcontinent and the Arabian Peninsula. The Southern Cone of South America and Alaskan peninsula of North America are other examples.
In many of these cases, the "subcontinents" concerned are on different tectonic plates from the rest of the continent, providing a geological justification for the terminology. Greenland, generally reckoned as the worlds largest island on the northeastern periphery of the North American Plate, is sometimes referred to as a subcontinent. This is a significant departure from the more conventional view of a subcontinent as comprising a very large peninsula on the fringe of a continent.
Where the Americas are viewed as a single continent America, it is divided into two subcontinents North America and South America or three with Central America being the third. When Eurasia is regarded as a single continent, Europe is treated as a subcontinent.
3.3. Other divisions Submerged continents
Some areas of continental crust are largely covered by the sea and may be considered submerged continents. Notable examples are Zealandia, emerging from the sea primarily in New Zealand and New Caledonia, and the almost completely submerged Kerguelen Plateau in the southern Indian Ocean.
3.4. Other divisions Microcontinents
Some islands lie on sections of continental crust that have rifted and drifted apart from a main continental landmass. While not considered continents because of their relatively small size, they may be considered microcontinents. Madagascar, the largest example, is usually considered an island of Africa, but its divergent evolution has caused it to be referred to as "the eighth continent" from a biological perspective.
3.5. Other divisions Botanical continents
"Continents" may be defined differently for specific purposes. The Biodiversity Information Standards organization has developed the World Geographical Scheme for Recording Plant Distributions, used in many international plant databases. This scheme divides the world into nine "botanical continents". Some match the traditional geographical continents, but some differ significantly. Thus the Americas are divided between Northern America Mexico northwards and Southern America Central America and the Caribbean southwards rather than between North America and South America.
4.1. History of the concept Early concepts of the Old World continents
The term "continent" translates Greek ἤπειρος, properly "landmass, terra firma", the proper name of Epirus and later especially used of Asia i.e. Asia Minor, The first distinction between continents was made by ancient Greek mariners who gave the names Europe and Asia to the lands on either side of the waterways of the Aegean Sea, the Dardanelles strait, the Sea of Marmara, the Bosporus strait and the Black Sea. The names were first applied just to lands near the coast and only later extended to include the hinterlands. But the division was only carried through to the end of navigable waterways and ". beyond that point the Hellenic geographers never succeeded in laying their finger on any inland feature in the physical landscape that could offer any convincing line for partitioning an indivisible Eurasia."
Ancient Greek thinkers subsequently debated whether Africa then called Libya should be considered part of Asia or a third part of the world. Division into three parts eventually came to predominate. From the Greek viewpoint, the Aegean Sea was the center of the world; Asia lay to the east, Europe to the north and west, and Africa to the south. The boundaries between the continents were not fixed. Early on, the Europe–Asia boundary was taken to run from the Black Sea along the Rioni River known then as the Phasis in Georgia. Later it was viewed as running from the Black Sea through Kerch Strait, the Sea of Azov and along the Don River known then as the Tanais in Russia. The boundary between Asia and Africa was generally taken to be the Nile River. Herodotus in the 5th century BC objected to the whole of Egypt being split between Asia and Africa "Libya" and took the boundary to lie along the western border of Egypt, regarding Egypt as part of Asia. He also questioned the division into three of what is really a single landmass, a debate that continues nearly two and a half millennia later.
Eratosthenes, in the 3rd century BC, noted that some geographers divided the continents by rivers the Nile and the Don, thus considering them "islands". Others divided the continents by isthmuses, calling the continents "peninsulas". These latter geographers set the border between Europe and Asia at the isthmus between the Black Sea and the Caspian Sea, and the border between Asia and Africa at the isthmus between the Red Sea and the mouth of Lake Bardawil on the Mediterranean Sea.
Through the Roman period and the Middle Ages, a few writers took the Isthmus of Suez as the boundary between Asia and Africa, but most writers continued to consider it the Nile or the western border of Egypt Gibbon. In the Middle Ages, the world was usually portrayed on T and O maps, with the T representing the waters dividing the three continents. By the middle of the 18th century, "the fashion of dividing Asia and Africa at the Nile, or at the Great Catabathmus farther west, had even then scarcely passed away".
4.2. History of the concept European arrival in the Americas
Christopher Columbus sailed across the Atlantic Ocean to the West Indies in 1492, sparking a period of European exploration of the Americas. But despite four voyages to the Americas, Columbus never believed he had reached a new continent - he always thought it was part of Asia.
In 1501, Amerigo Vespucci and Gonçalo Coelho attempted to sail around what they considered the southern end of the Asian mainland into the Indian Ocean, passing through Fernando de Noronha. After reaching the coast of Brazil, they sailed a long way further south along the coast of South America, confirming that this was a land of continental proportions and that it also extended much further south than Asia was known to. On return to Europe, an account of the voyage, called Mundus Novus "New World", was published under Vespuccis name in 1502 or 1503, although it seems that it had additions or alterations by another writer. Regardless of who penned the words, Mundus Novus credited Vespucci with saying, "I have discovered a continent in those southern regions that is inhabited by more numerous people and animals than our Europe, or Asia or Africa", the first known explicit identification of part of the Americas as a continent like the other three.
Within a few years, the name "New World" began appearing as a name for South America on world maps, such as the Oliveriana Pesaro map of around 1504–1505. Maps of this time though, still showed North America connected to Asia and showed South America as a separate land.
In 1507 Martin Waldseemuller published a world map, Universalis Cosmographia, which was the first to show North and South America as separate from Asia and surrounded by water. A small inset map above the main map explicitly showed for the first time the Americas being east of Asia and separated from Asia by an ocean, as opposed to just placing the Americas on the left end of the map and Asia on the right end. In the accompanying book Cosmographiae Introductio, Waldseemuller noted that the earth is divided into four parts, Europe, Asia, Africa and the fourth part, which he named "America" after Amerigo Vespuccis first name. On the map, the word "America" was placed on part of South America.
4.3. History of the concept The word continent
From the 16th century the English noun continent was derived from the term continent land, meaning continuous or connected land and translated from the Latin terra continens. The noun was used to mean "a connected or continuous tract of land" or mainland. It was not applied only to very large areas of land - in the 17th century, references were made to the continents or mainlands of Isle of Man, Ireland and Wales and in 1745 to Sumatra. The word continent was used in translating Greek and Latin writings about the three "parts" of the world, although in the original languages no word of exactly the same meaning as continent was used.
While continent was used on the one hand for relatively small areas of continuous land, on the other hand geographers again raised Herodotuss query about why a single large landmass should be divided into separate continents. In the mid-17th century, Peter Heylin wrote in his Cosmographie that "A Continent is a great quantity of Land, not separated by any Sea from the rest of the World, as the whole Continent of Europe, Asia, Africa." In 1727, Ephraim Chambers wrote in his Cyclopædia, "The world is ordinarily divided into two grand continents: the old and the new." And in his 1752 atlas, Emanuel Bowen defined a continent as "a large space of dry land comprehending many countries all joined together, without any separation by water. Thus Europe, Asia, and Africa is one great continent, as America is another." However, the old idea of Europe, Asia and Africa as "parts" of the world ultimately persisted with these being regarded as separate continents.
4.4. History of the concept Beyond four continents
From the late 18th century, some geographers started to regard North America and South America as two parts of the world, making five parts in total. Overall though, the fourfold division prevailed well into the 19th century.
Europeans discovered Australia in 1606, but for some time it was taken as part of Asia. By the late 18th century, some geographers considered it a continent in its own right, making it the sixth or fifth for those still taking America as a single continent. In 1813, Samuel Butler wrote of Australia as "New Holland, an immense island, which some geographers dignify with the appellation of another continent" and the Oxford English Dictionary was just as equivocal some decades later. It was in the 1950s that the concept of Oceania as a "great division" of the world was replaced by the concept of Australia as a continent.
Antarctica was sighted in 1820 during the First Russian Antarctic Expedition and described as a continent by Charles Wilkes on the United States Exploring Expedition in 1838, the last continent identified, although a great "Antarctic" antipodean landmass had been anticipated for millennia. An 1849 atlas labelled Antarctica as a continent but few atlases did so until after World War II.
From the mid-19th century, atlases published in the United States more commonly treated North and South America as separate continents, while atlases published in Europe usually considered them one continent. However, it was still not uncommon for American atlases to treat them as one continent up until World War II. From the 1950s, most U.S. geographers divided the Americas into two continents. With the addition of Antarctica, this made the seven-continent model. However, this division of the Americas never appealed to Latin Americans, who saw their region spanning an America as a single landmass, and there the conception of six continents remains dominant, as it does in scattered other countries.
Some geographers regard Europe and Asia together as a single continent, dubbed Eurasia. In this model, the world is divided into six continents, with North America and South America considered separate continents.
Geologists use the term continent in a different manner from geographers. In geology a continent is defined by continental crust: a platform of metamorphic and igneous rock, largely of granitic composition. Some geologists restrict the term continent to portions of the crust built around stable Precambrian "shield", typically 1.5 to 3.8 billion years old, called a craton. The craton itself is an accretionary complex of ancient mobile belts mountain belts from earlier cycles of subduction, continental collision and break-up from plate tectonic activity. An outward-thickening veneer of younger minimally deformed sedimentary rock covers much of the craton. The margins of geologic continents are characterized by currently active or relatively recently active mobile belts and deep troughs of accumulated marine or deltaic sediments. Beyond the margin, there is either a continental shelf and drop off to the basaltic ocean basin or the margin of another continent, depending on the current plate-tectonic setting of the continent. A continental boundary does not have to be a body of water. Over geologic time, continents are periodically submerged under large epicontinental seas, and continental collisions result in a continent becoming attached to another continent. The current geologic era is relatively anomalous in that so much of the continental areas are "high and dry"; that is, many parts of the continents that were once below sea level are now elevated well above it due to changes in sea levels and the subsequent uplifting of those continental areas from tectonic activity.
Some argue that continents are accretionary crustal "rafts" that, unlike the denser basaltic crust of the ocean basins, are not subjected to destruction through the plate tectonic process of subduction. This accounts for the great age of the rocks comprising the continental cratons. By this definition, Eastern Europe, India and some other regions could be regarded as continental masses distinct from the rest of Eurasia because they have separate ancient shield areas i.e. East European craton and Indian craton. Younger mobile belts such as the Ural Mountains and Himalayas mark the boundaries between these regions and the rest of Eurasia.
There are many microcontinents, or continental fragments, that are built of continental crust but do not contain a craton. Some of these are fragments of Gondwana or other ancient cratonic continents: Zealandia, which includes New Zealand and New Caledonia; Madagascar; the northern Mascarene Plateau, which includes the Seychelles. Other islands, such as several in the Caribbean Sea, are composed largely of granitic rock as well, but all continents contain both granitic and basaltic crust, and there is no clear boundary as to which islands would be considered microcontinents under such a definition. The Kerguelen Plateau, for example, is largely volcanic, but is associated with the breakup of Gondwanaland and is considered a microcontinent, whereas volcanic Iceland and Hawaii are not. The British Isles, Sri Lanka, Borneo, and Newfoundland are margins of the Laurasian continent - only separated by inland seas flooding its margins.
Plate tectonics offers yet another way of defining continents. Today, Europe and most of Asia constitute the unified Eurasian Plate, which is approximately coincident with the geographic Eurasian continent excluding India, Arabia, and far eastern Russia. India contains a central shield, and the geologically recent Himalaya mobile belt forms its northern margin. North America and South America are separate continents, the connecting isthmus being largely the result of volcanism from relatively recent subduction tectonics. North American continental rocks extend to Greenland a portion of the Canadian Shield, and in terms of plate boundaries, the North American plate includes the easternmost portion of the Asian landmass. Geologists do not use these facts to suggest that eastern Asia is part of the North American continent, even though the plate boundary extends there; the word continent is usually used in its geographic sense and additional definitions "continental rocks," "plate boundaries" are used as appropriate.
The movement of plates has caused the formation and break-up of continents over time, including occasional formation of a supercontinent that contains most or all of the continents. The supercontinent Columbia or Nuna formed during a period of 2.0–1.8 billion years ago and broke up about 1.5–1.3 billion years ago. The supercontinent Rodinia is thought to have formed about 1 billion years ago and to have embodied most or all of Earths continents, and broken up into eight continents around 600 million years ago. The eight continents later re-assembled into another supercontinent called Pangaea; Pangaea broke up into Laurasia which became North America and Eurasia and Gondwana which became the remaining continents.
6. Highest and lowest points
The following table lists the seven continents with their highest and lowest points on land, sorted in decreasing highest points.
† The lowest exposed points are given for North America and Antarctica. The lowest non-submarine bedrock elevations in these continents are the trough beneath Jakobshavn Glacier −1.512 metres −4.961 ft) and Bentley Subglacial Trench −2.540 metres −8.330 ft), but these are covered by kilometers of ice.
††Claimed by Australia as part of Australian Antarctic Territory, but this claim is not widely recognised.
Some sources list the Kuma–Manych Depression a remnant of the Paratethys as the geological border between Europe and Asia. This would place the Caucasus outside of Europe, thus making Mont Blanc elevation 4810 m in the Graian Alps the highest point in Europe – the lowest point would still be the shore of the Caspian Sea.
- Lewis, Martin W.; Wigen, Karen E. 1997. The Myth of Continents: a Critique of Metageography. Berkeley: University of California Press. ISBN 978-0-520-20743-1.
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|Definition of Continent by Merriam Webster. Feb 17, 2017 Its almost all under water, but Zealandia should be considered a continent, say researchers.. .. Continent Type. Credits global users, purchases of Shopping Cards and also you earn Points from your activities, such as to day access,. .. The Last Continent PBS NewsHour. continent. exists to promote and explore thinking across a variety of media.. .. Hotel du Continent in Paris by Christian Lacroix. Feb 15, 2017 Kids are frequently taught that seven continents exist: Africa, Asia, Antarctica, Australia, Europe, North, and South America. Geologists. .. Definition of Continent at. Christian Lacroix designed decor of Hotel du Continent. Each floor represents a landmass: Europe, the Poles, Oceania, Asia, Africa and America.. .. The Continent Hotel Bangkok by Compass Hospitality 5 Star. Sep 11, 2019 The lost continent Greater Adria existed hundreds millions of years ago after it broke off from Gondwana.. .. 8th Continent® Soy Beverage From Our Family To Yours.. Sep 6, 2019 Forget the legendary lost continent Atlantis. Geologists have reconstructed, by time slice, nearly quarter of a billion year long. .. Foresight Africa: Top priorities for the continent 2020 2030. Jan 8, 2020 Through at least first half decade, economic growth across Africa will continue to outperform that of other regions, with the continent. .. How African feng shui can shape continents cities of the future. Explore Mid Continent Public. New titles, rated, and recently tagged by the library community.. .. What are Continents? YouTube. About 200 years ago, Antarctica was barely an idea. Today its a world of scientific possibility. How did we get here and what will happen as climate change.||Log In Mid Continent Public Library BiblioCommons. 1 day ago Nowadays, theres a sufficient cohort of architects who have some relationship to the continent - either been trained here, or having. .. Zealandia: Is there an eighth continent under New Zealand? BBC. Type: Continent One of the continents for example, Europe or Africa.. .. Earth Has a New Continent Called Zealandia, Study Reveals. Sep 15, 2011 Help support videos like this: CGPGrey T Shirts for sale! Full script at:. .. Theres a Lost Continent Hiding Beneath Europe Live Science. definition is one six or seven great divisions of land on the globe. How to use continent in a sentence.. .. Geologists uncover history of lost continent buried beneath Europe. Official website A Boutique 5 Star Lifestyle Hotel Located Near Terminal 21 Shopping Mall, Sukhumvit MRT Subway Station and Asoke BTS Skytrain. .. SixthContinent. Continent definition, one main landmasses of the globe, usually reckoned as seven in number Europe, Asia, Africa, North, South America,. .. continent.. Continent, one the larger continuous masses land, namely, Asia, Africa, North, South America, Antarctica, Europe, and Australia, listed in order of. .. Mid Continent Public Library: Home. 8th Continent® Soymilk made by Lou Stremick and his four children, but we like to think that every employee is part of the family.. .. continent Definition, Map, & Facts Britannica. Raytown reopened Monday, January 27 Buckner Branch reopens on Wednesday, February 5. Make plans to stop by and see the.|
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Pino - logical board game which is based on tactics and strategy. In general this is a remix of chess, checkers and corners. The game develops imagination, concentration, teaches how to solve tasks, plan their own actions and of course to think logically. It does not matter how much pieces you have, the main thing is how they are placement!online intellectual game →