What are the eight continents

what are the eight continents

Earth Apparently Has 8 Continents Now, Because Everything You Know Is a Lie

Feb 21,  · If you took geography classes as a child, you were probably taught that Earth has seven continents: North America South America Africa Europe Asia Australia Antarctica But . Feb 18,  · Earth has eight continents, and world maps should reflect this, geologists say. The eighth, a lost continent called Zealandia, isn't a huge landmass that geographers have somehow missed.

A continent is one of several large landmasses. Generally identified by convention rather than any strict criteria, up to seven regions are commonly regarded as continents. Geologicallythe continents correspond to areas of continental crust that are found on the continental platesbut include continental fragments such as Madagascar that are not commonly referred to as continents while others are largely covered with watersuch as Zealandia.

Continental crust is only known to exist on Earth. Oceanic islands are frequently grouped with a neighbouring continent to divide all the world's land into regions. Under this scheme, most eigbt the island countries and territories in the Pacific Ocean are grouped together with the continent of Australia to form a region called Oceania.

By convention, "continents are understood to be large, continuous, discrete masses of land, what are the eight continents separated by expanses of water. The criterion "large" leads to arbitrary classification: Greenlandwith a surface area of 2, square kilometresthee miis considered the world's largest island, while Australiaat 7, square kilometres 2, sq miis deemed the smallest continent.

Earth 's major landmasses all have coasts on a single, continuous World Oceanwhich is divided into a number of principal oceanic components what are the eight continents the continents and various geographic criteria. The most restricted meaning of continent is that of a continuous [6] 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 Cntinents, excluding islands such as Great BritainIcelandIrelandand Malta while the term continent of Australia may refer to the mainland of Australiaexcluding New GuineaTasmaniaand other nearby islands.

Similarly, the continental United States refers to the 48 contiguous states and the District of Columbia and may include Alaska in the northwest of the continent the two being separated by Canadawhile excluding Hawaii in the Pacific Ocean. From the perspective of geology or physical geographycontinent may be extended beyond the confines of continuous dry land to include the shallow, submerged adjacent area the continental shelf [7] and the islands on the shelf continental islandsas 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. As a cultural constructthe 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 eigght one "quasi-continent" called Oceania.

This divides the entire land surface of Earth into continents or quasi-continents. 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". In both cases, there is no complete separation of these landmasses by water disregarding the Suez Canal and Panama Canalwhich are both narrow and shallow, as well as man-made.

Both of 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.

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, square kilometres 3, sq miwhile South Asia, with less than half that area, is considered a subcontinent.

The what are the eight continents 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.

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. When sea levels were lower during the Pleistocene ice agesgreater areas of continental shelf were exposed as dry land, forming land bridges between Tasmania and Australian mainland. At those times Australia—New Guinea was a single, continuous continent. Other islands such as Great Britain were joined to what are the eight continents mainlands of their continents.

There are several ways of distinguishing the continents:. As previously mentioned, some geographers use the name Oceania for a region including most of the island countries and territories in the Pacific Ocean as well as the continent of Australia.

The following table summarizes the area and population of the continental regions used by the United Nations. The total land area of all continents is , square kilometres 57, sq mior Apart from the current continents, the scope and meaning of the term continent includes past geological ones.

Supercontinentslargely in evidence earlier in the geological record, are what is the average age in the world that comprise more than one craton or continental core. Over time, these supercontinents broke apart into large land masses which formed the present continents. 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. 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. Where the Americas are viewed as a single continent Americait is divided into two subcontinents North America and South America [47] [48] [49] or three with Central America being the third.

Some areas of continental crust are eigyt covered by the sea and may be xre submerged continents. Notable examples are Zealandiaemerging from the sea primarily in New Zealand and New Caledonia[52] and the what are the eight continents completely submerged Kerguelen Plateau in the southern Indian Ocean.

Some islands lie age sections of continental crust that what are the eight continents rifted and drifted apart from a main continental landmass. While not considered continents because of their relatively small size, they may be considered microcontinents.

Madagascarthe 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. Asia Minor[55] The first distinction between continents was made by ancient Greek contibents who gave the names Europe and Asia to the lands on either side of the waterways of the Aegean Seathe Dardanelles strait, the Sea of Marmarathe Bosporus strait and the Black Sea.

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 what are the eight continents came to predominate. Herodotus [61] 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 what are the eight continents of what is really a single landmass, [62] a conrinents that continues nearly two and a half millennia later.

Eratosthenesin the 3rd century BC, noted that some geographers divided the continents by rivers how to break into a money box Nile and the Donthus considering them "islands".

Others divided the continents by isthmusescalling the continents "peninsulas". These latter geographers set the border between Europe and Asia at the isthmus between the Black Sea and the Caspian Seaand 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 Agesa few writers what are the eight continents 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.

By the middle rhe the 18th century, "the fashion of dividing Asia and Africa at the Nile, or at the Great Catabathmus [the boundary between Egypt and Libya ] farther west, had even then scarcely passed away". Christopher Columbus sailed across the Atlantic Ocean to the West Indies insparking 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 continehts thought it was part what are the eight continents Asia.

After reaching the coast of Brazilthey sailed a long way farther south along the coast of South Americaconfirming that this was a land of continental proportions and that it also extended much farther south than Asia was known to. Within how to make an automatic plant waterer few years, the name "New World" began appearing as a name for South America on world maps, such as the Oliveriana Pesaro map of what are the eight continents — Maps of this time though, contijents showed North America connected to Asia and showed South America as a separate land.

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 eigut and Contunents on the right end. From the 16th century the English what are the eight continents continent was derived from the term continent landmeaning continuous or connected what are the eight continents [70] and translated from the Latin terra continens.

While continent was used on the one hand for relatively small eitht of continuous land, on the other hand geographers again raised Herodotus's query about why a single large landmass should be divided into separate continents. Thus Europe, Asia, and Africa is one great continent, as America is another. 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. Hhe discovered Australia inbut for some time it was taken as part of Continenfs.

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. Antarctica was sighted in during the First Russian Antarctic Expedition and described as a continent by Charles Wilkes continenrs the United States Exploring Expedition wrethe last continent identified, although a great "Antarctic" antipodean landmass had been anticipated for millennia. From the midth century, atlases published in the United States more commonly treated How to draw a telephone booth 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 continentss as one continent up until World War II. Some geographers regard Europe and Asia together as a single continent, dubbed Eurasia.

Geologists use the term continent in a different manner from geographers. In geology, a continent is defined by continental crust, which is a platform of metamorphic and igneous rocklargely of granitic composition.

Continental crust is less dense and much thicker than oceanic crust, which causes it to "float" higher than oceanic crust on the dense underlying mantle. This explains why the continents form high platforms surrounded by deep ocean basins.

Some geologists restrict the term 'continent' to portions of the crust built around stable regions called cratons. Cratons have largely been unaffected by mountain-building events orogenies since the Precambrian.

A craton typically consists of a continental shield surrounded by a continental platform. The shield is a region where ancient crystalline basement rock typically 1. The platform vontinents the shield is also composed of ancient basement rock, but with a cover of younger sedimentary rock. This accounts for the great age of the rocks comprising the continental cratons. The margins of geologic continents what are the eight continents characterized by currently active or relatively recently active mobile what is 160c in fahrenheit and deep troughs of accumulated marine or deltaic sediments.

Beyond the margin, there is what is the weather like in ibiza in june 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. 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. East European craton and Indian craton. Younger mobile belts such as the Ural What are the eight continents and Himalayas mark the boundaries between these regions and the rest of Eurasia.

Plate tectonics provides yet another way of defining continents. Today, Europe and most of Asia constitute the unified Eurasian Platewhich is approximately continentts 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 eigbt to Greenland how to open archived mails in gmail portion of the Canadian Shieldand 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 whag 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.

Navigation menu

Feb 17,  · It’s time to get rid of every piece of literature that says Africa, Antartica, Australia, South America, North America, Europe and Asia (or Eurasia) are the only continents, because apparently. There are seven continents in the world: Africa, Antarctica, Asia, Australia/Oceania, Europe, North America, and South America. However, depending on where you live, you may have learned that there are five, six, or even four continents. This is because there is no official criteria for determining continents.

The eighth, a lost continent called Zealandia, isn't a huge landmass that geographers have somehow missed. Rather, only small bits — including New Zealand, New Caledonia and a few other specks of land in the vast Pacific Ocean — are above sea level. The rest of this continent lies beneath the waves, a new study suggests. The new study synthesizes decades of evidence for a hidden continent lying beneath the ocean surrounding New Zealand.

The first line of evidence comes simply from looking at the ocean floor around New Zealand: The continental shelves of Zealandia lie at a depth of about 3, feet 1, meters below sea level, while the nearby oceanic crust is about 9, feet 3, m below that, Mortimer said. The second line of evidence supporting Zealandia's designation as a separate continent comes from extensive study of the rocks beneath the ocean. Over the past 20 years, geologists have set sail on ships to dredge rocks from the seafloor.

Unlike the nearby oceanic crust, which is made up of basaltic rocks from the fairly recent geologic past, the crust surrounding New Zealand is composed of a variety of different rock types, including granite, limestone and sandstone, some of which are incredibly ancient.

Finally, scientists have shown that there's a narrow strip of oceanic crust separating the continent of Australia from the subterranean reaches of Zealandia, meaning the two are separate continents, Mortimer said.

Zealandia was born from the breakup of the supercontinent of Gondwana , about 85 million years ago, Mortimer said. At that time, an ocean began to emerge between Australia and New Zealand.

That stretching essentially thinned out the continental crust, making it sink more than thicker continental crust, which tends to float, he said. Compared with other continents, Zealandia is pint-size; at 1. And although only a tiny amount of the continent is lying above the water currently, at one time, its above-water footprint was even smaller. Based on geologic layers unearthed on New Zealand, the continent reached its maximum level of submergence about 30 million years ago, Mortimer said.

Now, the movement of the Australian plate is cutting Zealandia in two, which should break the continent in half in tens of millions of years, Mortimer said. While the new findings are unlikely to change seismological maps or hazard assessments around New Zealand , "I think it will focus minds; it's just a more correct depiction of the geology and tectonics of this corner of the planet," Mortimer said.

From a geological perspective, defining Zealandia as a continent makes sense, said Bruce Luyendyk, a professor emeritus in geology at the Univeristy of California at Santa Barbara, who first coined the term "Zealandia. As to whether maps should reflect this geologic reality, "That's a question answered by geographers and politicians, not geologists," Luyendyk told Live Science.

But there's some precedent for recognizing the continental boundaries that lie beneath the water, Luyendyk said. Other continents have continental shelves that project deeper out into the ocean, and the United Nations Convention on the Law of the Sea, which sets the economic limits of a nation along its coastline, already recognizes these geologic boundaries, Luyendyk said.

Originally published on Live Science. Live Science. Please deactivate your ad blocker in order to see our subscription offer.

More articles in this category:
<- How to do conversions using the ladder method - How to uninstall norton safety minder without password->

2 thoughts on “What are the eight continents

Add a comment

Your email will not be published. Required fields are marked *

Back to top