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Pangaea or Pangea () was a
supercontinent In geology Geology (from the Ancient Greek Ancient Greek includes the forms of the Greek language Greek ( el, label=Modern Greek Modern Greek (, , or , ''Kiní Neoellinikí Glóssa''), generally referred to by speakers sim ...
that existed during the late
Paleozoic The Paleozoic (or Palaeozoic) Era ( ; from the Greek#REDIRECT Greek Greek may refer to: Greece Anything of, from, or related to Greece Greece ( el, Ελλάδα, , ), officially the Hellenic Republic, is a country located in Southeast Eu ...
and early
Mesozoic The Mesozoic Era ( ), also called the Age of Reptiles and the Age of Conifers, is the second-to-last era An era is a span of time defined for the purposes of chronology or historiography, as in the regnal eras in the history of a given monarchy ...
eras. It assembled from earlier continental units during the
Carboniferous The Carboniferous ( ) is a geologic period The geologic time scale (GTS) is a system of chronological dating that classifies Geology, geological strata (stratigraphy) in time. It is used by geologists, paleontology, paleontologists, and other ...
approximately 335 million years ago, and began to break apart about 200 million years ago, at the end of the
Triassic The Triassic ( ) is a geologic period The geologic time scale (GTS) is a system of chronological dating that classifies Geology, geological strata (stratigraphy) in time. It is used by geologists, paleontology, paleontologists, and other earth ...
and beginning of the
Jurassic The Jurassic ( ) is a geologic period The geologic time scale (GTS) is a system of chronological dating that classifies Geology, geological strata (stratigraphy) in time. It is used by geologists, paleontology, paleontologists, and other earth ...
. In contrast to the present
Earth Earth is the third planet from the Sun and the only astronomical object known to harbour and support life. 29.2% of Earth's surface is land consisting of continents and islands. The remaining 70.8% is Water distribution on Earth, covered wi ...

Earth
and its distribution of continental mass, Pangaea was centred on the
Equator The Equator is a circle of latitude, about in circumference, that divides Earth into the Northern Hemisphere, Northern and Southern Hemisphere, Southern hemispheres. It is an imaginary line located at 0 degrees latitude, halfway between the N ...

Equator
and surrounded by the
superocean A superocean is an ocean The ocean (also the sea or the world ocean) is the body of salt water which covers approximately 71% of the surface of the Earth.
Panthalassa Panthalassa, also known as the Panthalassic Ocean or Panthalassan Ocean (from Greek Greek may refer to: Greece Anything of, from, or related to Greece Greece ( el, Ελλάδα, , ), officially the Hellenic Republic, is a country located i ...
and the
Paleo-Tethys The Paleo-Tethys or Palaeo-Tethys Ocean was an ocean The ocean (also the sea or the world ocean) is the body of salt water which covers approximately 71% of the surface of the Earth.
and subsequent Tethys Oceans. Pangaea is the most recent supercontinent to have existed and the first to be reconstructed by
geologist A geologist is a scientist who studies the solid, liquid, and gaseous matter that constitutes Earth and other terrestrial planets, as well as the processes that shape them. Geologists usually study geology, although backgrounds in physics, chem ...

geologist
s.


Origin of the concept

The name "Pangaea/Pangea" is derived from
Ancient Greek Ancient Greek includes the forms of the Greek language Greek ( el, label=Modern Greek Modern Greek (, , or , ''Kiní Neoellinikí Glóssa''), generally referred to by speakers simply as Greek (, ), refers collectively to the diale ...
''pan'' (, "all, entire, whole") and ''
Gaia In Greek mythology Greek mythology is the body of myth Myth is a folklore genre Folklore is the expressive body of culture shared by a particular group of people; it encompasses the tradition A tradition is a belief A be ...
'' or Gaea (, "
Mother Earth
Mother Earth
, land"). The concept that the continents once formed a contiguous land mass was hypothesised, with corroborating evidence, by
Alfred Wegener Alfred Lothar Wegener (; ; 1 November 1880 – November 1930) was a German polar researcher, geophysicist and meteorologist. During his lifetime he was primarily known for his achievements in meteorology and as a pioneer of polar researc ...

Alfred Wegener
, the originator of the
scientific theory A scientific theory is an explanation of an aspect of the natural science, natural world and universe that has been reproducibility, repeatedly tested and verified in accordance with the scientific method, using accepted protocol (science), protoc ...
of
continental drift Continental drift is the hypothesis that the Earth's continent A continent is one of several large landmasses. Generally identified by convention (norm), convention rather than any strict criteria, up to seven regions are commonly reg ...
, in his 1912 publication ''The Origin of Continents'' (''Die Entstehung der Kontinente'').Alfred Wegener: ''Die Entstehung der Kontinente.'' Dr. A. Petermann's Mitteilungen aus Justus Perthes' Geographischer Anstalt, 58(1): Gotha 1912 He expanded upon his hypothesis in his 1915 book ''The Origin of Continents and Oceans'' (''Die Entstehung der Kontinente und Ozeane''), in which he postulated that, before breaking up and drifting to their present locations, all the continents had formed a single
supercontinent In geology Geology (from the Ancient Greek Ancient Greek includes the forms of the Greek language Greek ( el, label=Modern Greek Modern Greek (, , or , ''Kiní Neoellinikí Glóssa''), generally referred to by speakers sim ...
that he called the "''Urkontinent''". The name "Pangea" occurs in the 1920 edition of ''Die Entstehung der Kontinente und Ozeane'', but only once, when Wegener refers to the ancient supercontinent as "the Pangaea of the Carboniferous". Wegener used the Germanized form "Pangäa," but the name entered German and English scientific literature (in 1922 and 1926, respectively) in the Latinized form "Pangaea" (of the Greek "Pangaia"), especially due to a symposium of the
American Association of Petroleum Geologists The American Association of Petroleum Geologists (AAPG) is one of the world's largest professional geological societies with more than 40,000 members across 129 countries as of 2021. The AAPG works to "advance the science of geology, especially as i ...
in November 1926.Willem A. J. M. van Waterschoot van der Gracht (and 13 other authors): ''Theory of Continental Drift: a Symposium of the Origin and Movements of Land-masses of both Inter-Continental and Intra-Continental, as proposed by Alfred Wegener.'' X + 240 S., Tulsa, Oklahoma, United States, The American Association of Petroleum Geologists & London, Thomas Murby & Co. Wegener originally proposed that the breakup of Pangaea was due to
centripetal forces
centripetal forces
from the Earth's rotation acting on the high continents. However, this mechanism was easily shown to be physically implausible, which delayed acceptance of the Pangaea hypothesis.
Arthur Holmes Arthur Holmes (14 January 1890 – 20 September 1965) was a British geologist who made two major contributions to the understanding of geology. He pioneered the use of radiometric dating of minerals and was the first earth scientist to grasp th ...
proposed the more plausible mechanism of
mantle convection Mantle convection is the very slow creeping motion of Earth's solid silicate mantle caused by convection Convection is single or multiphase fluid flow that occurs spontaneously due to the combined effects of material property heteroge ...
, which, together with evidence provided by the mapping of the ocean floor following the
Second World War World War II or the Second World War, often abbreviated as WWII or WW2, was a global war A world war is "a war War is an intense armed conflict between states State may refer to: Arts, entertainment, and media Literatur ...
, led to the development and acceptance of the theory of
plate tectonics Plate tectonics (from the la, label=Late Latin Late Latin ( la, Latinitas serior) is the scholarly name for the written Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. L ...
. This theory provides the now widely-accepted explanation for the existence and breakup of Pangaea.


Evidence of existence

The geography of the continents bordering the Atlantic Ocean was the first evidence suggesting the existence of Pangaea. The seemingly close fit of the coastlines of North and South America with Europe and Africa was remarked on almost as soon as these coasts were charted. The first to suggest that these continents were once joined and later separated may have been
Abraham Ortelius Abraham Ortelius (; also Ortels, Orthellius, Wortels; 14 April 152728 June 1598) was a Duchy of Brabant, Brabantian cartographer, geographer, and cosmographer, conventionally recognized as the creator of the list of atlases, first modern atlas, th ...

Abraham Ortelius
in 1596. Careful reconstructions showed that the mismatch at the contour was less than , and it was argued that this was much too good to be attributed to chance. Additional evidence for Pangaea is found in the
geology Geology (from the Ancient Greek Ancient Greek includes the forms of the Greek language Greek ( el, label=Modern Greek Modern Greek (, , or , ''Kiní Neoellinikí Glóssa''), generally referred to by speakers simply as Greek ...

geology
of adjacent continents, including matching geological trends between the eastern coast of
South America South America is a continent A continent is any of several large landmasses. Generally identified by convention (norm), convention rather than any strict criteria, up to seven geographical regions are commonly regarded as continent ...

South America
and the western coast of
Africa Africa is the world's second-largest and second-most populous continent A continent is any of several large landmass A landmass, or land mass, is a large region In geography Geography (from Greek: , ''geographia'', ...

Africa
. The
polar ice cap A polar ice cap or polar cap is a high-latitude In geography Geography (from Greek: , ''geographia'', literally "earth description") is a field of science devoted to the study of the lands, features, inhabitants, and phenomena o ...
of the
Carboniferous The Carboniferous ( ) is a geologic period The geologic time scale (GTS) is a system of chronological dating that classifies Geology, geological strata (stratigraphy) in time. It is used by geologists, paleontology, paleontologists, and other ...
Period covered the southern end of Pangaea. Glacial deposits, specifically
till image:Geschiebemergel.JPG, Closeup of glacial till. Note that the larger grains (pebbles and gravel) in the till are completely surrounded by the matrix of finer material (silt and sand), and this characteristic, known as ''matrix support'', is d ...

till
, of the same age and structure are found on many separate continents that would have been together in the continent of Pangaea.
Fossil A fossil (from Classical Latin Classical Latin is the form of Latin language Latin (, or , ) is a classical language A classical language is a language A language is a structured system of communication used by humans, inc ...

Fossil
evidence for Pangaea includes the presence of similar and identical species on continents that are now great distances apart. For example, fossils of the
therapsid Therapsida is a major group of eupelycosauria Eupelycosauria is a large clade A clade (; from grc, , ''klados'', "branch"), also known as a monophyletic group or natural group, is a group of organisms that are monophyly, monophyletic— ...

therapsid
''
Lystrosaurus ''Lystrosaurus'' (; 'shovel lizard'; proper Greek is λίστρον ''lístron'' ‘tool for leveling or smoothing, shovel, spade, hoe’) is an extinct genus of herbivorous A herbivore is an animal Animals (also called Metazoa) ...

Lystrosaurus
'' have been found in
South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. With over 60 million people, it is the world's 23rd-most populous nation and covers an area of . South Africa has three capital citie ...

South Africa
,
India India, officially the Republic of India (Hindi Hindi (Devanagari: , हिंदी, ISO 15919, ISO: ), or more precisely Modern Standard Hindi (Devanagari: , ISO 15919, ISO: ), is an Indo-Aryan language spoken chiefly in Hindi Belt, ...

India
and
Antarctica Antarctica ( or ) is Earth's southernmost continent. It contains the geographic South Pole and is situated in the Antarctic region of the Southern Hemisphere, almost entirely south of the Antarctic Circle, and is surrounded by the Southern Oc ...

Antarctica
, alongside members of the ''
Glossopteris ''Glossopteris'' ( grc, γλώσσα , meaning "tongue", because the leaves were tongue-shaped, and ''pteris'', Greek for fern or feathery) is the largest and best-known genus Genus (plural genera) is a taxonomic rank Taxonomy (general) is th ...

Glossopteris
'' flora, whose distribution would have ranged from the polar circle to the equator if the continents had been in their present position; similarly, the freshwater reptile ''
Mesosaurus ''Mesosaurus'' (meaning "middle lizard") is an extinct Extinction is the termination of a kind of organism In biology, an organism (from Ancient Greek, Greek: ὀργανισμός, ''organismos'') is any individual contiguous system ...

Mesosaurus
'' has been found in only localized regions of the coasts of
Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At 8.5 million square kilometers (3.2 million square miles) and with over 211 mill ...

Brazil
and
West Africa West Africa or Western Africa is the westernmost region of Africa. The United Nations defines Western Africa as the 17 countries of Benin, Burkina Faso, Cape Verde, The Gambia, Ghana, Guinea, Guinea-Bissau, Ivory Coast, Liberia, Mali, Mauritania ...

West Africa
.
Paleomagnetic Paleomagnetism, or palaeomagnetism, is the study of the record of the Earth's magnetic field Earth's magnetic field, also known as the geomagnetic field, is the magnetic field A magnetic field is a vector field that describes the magnet ...
study of apparent polar wandering paths also support the theory of a supercontinent. Geologists can determine the movement of continental plates by examining the orientation of magnetic minerals in rocks; when rocks are formed, they take on the magnetic properties of the Earth and indicate in which direction the poles lie relative to the rock. Since the magnetic poles drift about the rotational pole with a period of only a few thousand years, measurements from numerous lavas spanning several thousand years are averaged to give an apparent mean polar position. Samples of
sedimentary rock Sedimentary rocks are types of rock Rock most often refers to: * Rock (geology) A rock is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its Chemical compoun ...

sedimentary rock
and
intrusive igneous rock , an igneous ''intrusion'' exposed when the surrounding softer rock eroded away Intrusive rock is formed when magma 300px, Lava flow on Hawaii (island), Hawaii. Lava is the extrusive equivalent of magma. Magma (from Ancient Greek μάγμα (' ...
have magnetic orientations that are typically an average of the "secular variation" in the orientation of
magnetic north The north magnetic pole is a point on the surface of Earth's Northern Hemisphere The Northern Hemisphere is the half of Earth Earth is the third planet from the Sun and the only astronomical object known to harbour and support li ...
because their
remanent Remanence or remanent magnetization or residual magnetism is the magnetization left behind in a ferromagnetic material (such as iron) after an external magnetic field is removed. Colloquially, when a magnet is "magnetized" it has remanence. The r ...
magnetizations are not acquired instantaneously. Magnetic differences between sample groups whose age varies by millions of years is due to a combination of
true polar wander True polar wander is a solid-body rotation of a planet or moon with respect to its spin axis, causing the geographic locations of the north North is one of the four compass points The points of the compass are the vectors by which planet ...

true polar wander
and the drifting of continents. The true polar wander component is identical for all samples, and can be removed, leaving geologists with the portion of this motion that shows continental drift and can be used to help reconstruct earlier continental positions. The continuity of mountain chains provides further evidence for Pangaea. One example of this is the
Appalachian Mountains The Appalachian Mountains, often called the Appalachians, are a system of mountains in eastern North America North America is a continent A continent is any of several large landmasses. Generally identified by convention (nor ...

Appalachian Mountains
chain, which extends from the southeastern
United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country Continental United States, primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., ...

United States
to the Caledonides of Ireland, Britain, Greenland, and
Scandinavia Scandinavia; Sami Places * Sápmi, a cultural region in Northern Europe * Sami, Burkina Faso, a district of the Banwa Province * Sami District, Gambia * Sami, Cephalonia, a municipality in Greece * Sami (ancient city), in Elis, Greece * Sa ...
.Merali, Zeeya and Skinner, Brian J. (2009) ''Visualizing Earth Science'', Wiley,


Formation

Pangaea is only the most recent supercontinent identified in the geologic record. The forming of supercontinents and their breaking up appears to have been cyclical through Earth's history. There may have been several others before Pangaea. Paleomagnetic measurements help geologists determine the latitude and orientation of ancient continental blocks, and newer techniques may help determine longitudes. Paleontology helps determine ancient climates, confirming latitude estimates from paleomagnetic measurements, and the distribution of ancient forms of life provides clues on which continental blocks were close to each other at particular geological moments. However, reconstructions of continents prior to the breakup of Pangea, including the ones in this section, remain partially speculative, and different reconstructions will differ in some details.


Previous supercontinents

The fourth-last supercontinent, called
Columbia Columbia may refer to: * Columbia (personification), the historical female national personification of the United States, and a poetic name for the Americas Places North America Natural features * Columbia Plateau, a geologic and geographic regio ...
or Nuna, appears to have assembled in the period 2.0–1.8 billion years ago (Ga). Columbia/Nuna broke up and the next supercontinent,
Rodinia Rodinia (from the Russian родить, ''rodit'', meaning "to beget, to give birth", or родина, ''rodina'', meaning "motherland, birthplace") was a Neoproterozoic supercontinent that assembled 1.1–0.9 billion years ago and broke up 750 ...

Rodinia
, formed from the
accretion Accretion may refer to: Science * Accretion (astrophysics), the formation of planets and other bodies by collection of material through gravity * Accretion (meteorology), the process by which water vapor in clouds forms water droplets around nucle ...
and assembly of its fragments. Rodinia lasted from about 1.3 Ga until about 750 million years ago, but its exact configuration and geodynamic history are not nearly as well understood as those of the later supercontinents,
Pannotia Pannotia (from Greek: ''pan- Pan may refer to: Prefix *''Pan-'', a prefix from the Greek language, Greek πᾶν, ''pan'', meaning "all", "of everything", or "involving all members" of a group ** , most but not all using the prefix People * Pan ...

Pannotia
and Pangaea. According to one reconstruction, when Rodinia broke up, it split into three pieces: the supercontinent of Proto-Laurasia, the supercontinent of Proto-Gondwana, and the smaller Congo craton. Proto-Laurasia and Proto-Gondwana were separated by the Proto-Tethys Ocean. Next Proto-Laurasia itself split apart to form the continents of
Laurentia Image:North america craton nps.gif, upright=1.4, Laurentia, also called the North American craton Laurentia or the North American Craton is a large continental craton that forms the Geology of North America, ancient geological core of North Ameri ...
,
Siberia Siberia (; rus, Сибирь, r=Sibir', p=sʲɪˈbʲirʲ, a=Ru-Сибирь.ogg) is an extensive geographical region, constituting all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has been a part of R ...
, and
Baltica Baltica is a paleocontinent A paleocontinent or palaeocontinent is a distinct area of continental crust 350px, The thickness of Crust (geology)#Earth's crust, Earth's crust (km) Continental crust is the layer of Igneous rock, igneous, Sedim ...
. Baltica moved to the east of Laurentia, and Siberia moved northeast of Laurentia. The splitting also created two new oceans, the
Iapetus Ocean upright=1.35, Reconstruction of how the Iapetus Ocean and surrounding continents might have been arranged during the late Ediacaran period (geology), period The Iapetus Ocean (pronounced ) was an ocean that existed in the late Neoproterozoic and e ...
and Paleoasian Ocean. Most of the above masses coalesced again to form the relatively short-lived supercontinent of
Pannotia Pannotia (from Greek: ''pan- Pan may refer to: Prefix *''Pan-'', a prefix from the Greek language, Greek πᾶν, ''pan'', meaning "all", "of everything", or "involving all members" of a group ** , most but not all using the prefix People * Pan ...

Pannotia
. This supercontinent included large amounts of land near the poles and, near the equator, only a relatively small strip connecting the polar masses. Pannotia lasted until 540  Ma, near the beginning of the
Cambrian The Cambrian Period ( ; sometimes symbolized Ꞓ) was the first geological period A geological period is one of the several subdivisions of geologic time enabling cross-referencing of rocks and geologic events from place to place. These peri ...
period and then broke up, giving rise to the continents of
Laurentia Image:North america craton nps.gif, upright=1.4, Laurentia, also called the North American craton Laurentia or the North American Craton is a large continental craton that forms the Geology of North America, ancient geological core of North Ameri ...
,
Baltica Baltica is a paleocontinent A paleocontinent or palaeocontinent is a distinct area of continental crust 350px, The thickness of Crust (geology)#Earth's crust, Earth's crust (km) Continental crust is the layer of Igneous rock, igneous, Sedim ...
, and the southern supercontinent of
Gondwana Gondwana () or Gondwanaland was a supercontinent In geology Geology (from the Ancient Greek γῆ, ''gē'' ("earth") and -λoγία, ''-logia'', ("study of", "discourse")) is an Earth science concerned with the solid Earth, the rock (ge ...

Gondwana
.


Formation of Euramerica (Laurussia)

In the
Cambrian The Cambrian Period ( ; sometimes symbolized Ꞓ) was the first geological period A geological period is one of the several subdivisions of geologic time enabling cross-referencing of rocks and geologic events from place to place. These peri ...
period, the continent of
Laurentia Image:North america craton nps.gif, upright=1.4, Laurentia, also called the North American craton Laurentia or the North American Craton is a large continental craton that forms the Geology of North America, ancient geological core of North Ameri ...
, which would later become
North America North America is a continent A continent is any of several large landmasses. Generally identified by convention (norm), convention rather than any strict criteria, up to seven geographical regions are commonly regarded as continen ...

North America
, sat on the
equator The Equator is a circle of latitude, about in circumference, that divides Earth into the Northern Hemisphere, Northern and Southern Hemisphere, Southern hemispheres. It is an imaginary line located at 0 degrees latitude, halfway between the N ...

equator
, with three bordering oceans: the Panthalassic Ocean to the north and west, the
Iapetus Ocean upright=1.35, Reconstruction of how the Iapetus Ocean and surrounding continents might have been arranged during the late Ediacaran period (geology), period The Iapetus Ocean (pronounced ) was an ocean that existed in the late Neoproterozoic and e ...
to the south, and the
Khanty Ocean Khanty or Khanty-Mansi Ocean was a small ocean located between Baltica and an island arc (the Kipchak Arc) near Siberia Siberia (; rus, Сибирь, r=Sibir', p=sʲɪˈbʲirʲ, a=Ru-Сибирь.ogg) is an extensive geographical region spa ...
to the east. In the Earliest
Ordovician The Ordovician ( ) is a geologic period The geologic time scale (GTS) is a system of chronological dating that classifies Geology, geological strata (stratigraphy) in time. It is used by geologists, paleontology, paleontologists, and other eart ...

Ordovician
, around 480 Ma, the microcontinent of
Avalonia Avalonia was a microcontinent in the Paleozoic The Paleozoic (or Palaeozoic) Era ( ; from the Greek ''palaiós'' (), "old" and ''zōḗ'' (), "life", meaning "ancient life") is the earliest of three geologic eras of the Phanerozoic Eon. It ...

Avalonia
– a landmass incorporating fragments of what would become eastern
Newfoundland Newfoundland and Labrador (, ) is the easternmost provinces and territories of Canada, province of Canada, in the country's Atlantic Canada, Atlantic region. It is composed of the island of Newfoundland (island), Newfoundland and the continental ...
, the southern
British Isles The British Isles are a group of islands in the North Atlantic off the north-western coast of continental Europe Continental Europe or mainland Europe is the contiguous continent A continent is any of several large landmasse ...

British Isles
, and parts of
Belgium Belgium ( nl, België ; french: Belgique ; german: Belgien ), officially the Kingdom of Belgium, is a country in Western Europe Western Europe is the western region of Europe. The region's countries and territories vary depending on cont ...

Belgium
, northern
France France (), officially the French Republic (french: link=no, République française), is a transcontinental country This is a list of countries located on more than one continent A continent is one of several large landmasses ...

France
,
Nova Scotia ) , image_map = Nova Scotia in Canada 2.svg , Label_map = yes , coordinates = , official_lang = English (''de facto'') , RegionalLang = French, Scots Gaelic , capital ...

Nova Scotia
,
New England New England is a region comprising six states in the Northeastern United States The Northeastern United States (also referred to as the American Northeast, the Northeast, and the East Coast) is a geographical region In geography ...

New England
, South
Iberia The Iberian Peninsula , ** * Aragonese language, Aragonese and Occitan language, Occitan: ''Peninsula Iberica'' ** ** * french: Péninsule Ibérique * mwl, Península Eibérica * eu, Iberiar penintsula also known as Iberia, is a penin ...

Iberia
, and northwest Africa – broke free from Gondwana and began its journey to
Laurentia Image:North america craton nps.gif, upright=1.4, Laurentia, also called the North American craton Laurentia or the North American Craton is a large continental craton that forms the Geology of North America, ancient geological core of North Ameri ...
. Baltica, Laurentia, and Avalonia all came together by the end of the Ordovician to form a landmass called
Euramerica Laurasia (), a portmanteau for Laurentia and Asia, was the more northern of two large landmasses (the other being Gondwana) that formed part of the Pangaea supercontinent from around (Mya (unit), Mya). It separated from Gondwana (beginning in t ...
or Laurussia, closing the Iapetus Ocean. The collision also resulted in the formation of the northern
Appalachians The Appalachian Mountains, often called the Appalachians, are a mountain range, system of mountains in eastern North America. The Appalachians first formed roughly 480 million years ago during the Ordovician, Ordovician Period. They once reache ...
.
Siberia Siberia (; rus, Сибирь, r=Sibir', p=sʲɪˈbʲirʲ, a=Ru-Сибирь.ogg) is an extensive geographical region, constituting all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has been a part of R ...
sat near Euramerica, with the
Khanty Ocean Khanty or Khanty-Mansi Ocean was a small ocean located between Baltica and an island arc (the Kipchak Arc) near Siberia Siberia (; rus, Сибирь, r=Sibir', p=sʲɪˈbʲirʲ, a=Ru-Сибирь.ogg) is an extensive geographical region spa ...
between the two continents. While all this was happening, Gondwana drifted slowly towards the South Pole. This was the first step of the formation of Pangaea.


Collision of Gondwana with Euramerica

The second step in the formation of Pangaea was the collision of Gondwana with Euramerica. By the middle of the
Silurian The Silurian ( ) is a geologic period and system spanning 24.6 million years from the end of the Ordovician The Ordovician ( ) is a geologic period A geological period is one of the several subdivisions of geologic time enabling cross-refere ...
, 430 Ma, Baltica had already collided with Laurentia, forming Euramerica, an event called the
Caledonian orogeny The Caledonian orogeny was a orogeny, mountain-building era recorded in the northern parts of the British Isles, the Scandinavian Mountains, Svalbard, East Greenland Orogen, eastern Greenland and parts of north-central Europe. The Caledonian orogeny ...
.
Avalonia Avalonia was a microcontinent in the Paleozoic The Paleozoic (or Palaeozoic) Era ( ; from the Greek ''palaiós'' (), "old" and ''zōḗ'' (), "life", meaning "ancient life") is the earliest of three geologic eras of the Phanerozoic Eon. It ...

Avalonia
had not yet collided with
Laurentia Image:North america craton nps.gif, upright=1.4, Laurentia, also called the North American craton Laurentia or the North American Craton is a large continental craton that forms the Geology of North America, ancient geological core of North Ameri ...
, but as Avalonia inched towards Laurentia, the seaway between them, a remnant of the
Iapetus Ocean upright=1.35, Reconstruction of how the Iapetus Ocean and surrounding continents might have been arranged during the late Ediacaran period (geology), period The Iapetus Ocean (pronounced ) was an ocean that existed in the late Neoproterozoic and e ...
, was slowly shrinking. Meanwhile,
southern Europe Southern Europe is the southern region In geography Geography (from Greek: , ''geographia'', literally "earth description") is a field of science devoted to the study of the lands, features, inhabitants, and phenomena of the Earth a ...

southern Europe
broke off from Gondwana and began to move towards Euramerica across the
Rheic Ocean The Rheic Ocean was an ocean The ocean (also the sea or the world ocean) is the body of salt water which covers approximately 71% of the surface of the Earth.world map, originally prepared by Joan Blaeu for his ''Atlas Maior'', published ...
. It collided with southern
Baltica Baltica is a paleocontinent A paleocontinent or palaeocontinent is a distinct area of continental crust 350px, The thickness of Crust (geology)#Earth's crust, Earth's crust (km) Continental crust is the layer of Igneous rock, igneous, Sedim ...
in the
Devonian The Devonian ( ) is a geologic period and system of the Paleozoic The Paleozoic (or Palaeozoic) Era ( ; from the Greek Greek may refer to: Greece Anything of, from, or related to Greece Greece ( el, Ελλάδα, , ), officially the H ...
. By the late Silurian, Annamia and
South China South China () is a geographical and cultural region that covers the southernmost part of China. Its precise meaning varies with context. A notable feature of South China in comparison to the rest of China is that most of its citizens are not ...
split from Gondwana and started to head northward, shrinking the Proto-Tethys Ocean in their path and opening the new
Paleo-Tethys Ocean The Paleo-Tethys or Palaeo-Tethys Ocean was an ocean The ocean (also the or the world ocean) is the body of that covers approximately 70.8% of the surface of and contains 97% of . Another definition is "any of the large bodies of water ...
to their south. In the Devonian Period, Gondwana itself headed towards Euramerica, causing the Rheic Ocean to shrink. In the Early
Carboniferous The Carboniferous ( ) is a geologic period The geologic time scale (GTS) is a system of chronological dating that classifies Geology, geological strata (stratigraphy) in time. It is used by geologists, paleontology, paleontologists, and other ...
, northwest
Africa Africa is the world's second-largest and second-most populous continent A continent is any of several large landmass A landmass, or land mass, is a large region In geography Geography (from Greek: , ''geographia'', ...

Africa
had touched the southeastern coast of
Euramerica Laurasia (), a portmanteau for Laurentia and Asia, was the more northern of two large landmasses (the other being Gondwana) that formed part of the Pangaea supercontinent from around (Mya (unit), Mya). It separated from Gondwana (beginning in t ...
, creating the southern portion of the
Appalachian Mountains The Appalachian Mountains, often called the Appalachians, are a system of mountains in eastern North America North America is a continent A continent is any of several large landmasses. Generally identified by convention (nor ...

Appalachian Mountains
, the Meseta Mountains, and the Mauritanide Mountains, an event called the
Variscan orogeny The Variscan or Hercynian orogeny was a geologic mountain-building event caused by Late Paleozoic The Paleozoic (or Palaeozoic) Era ( ; from the Greek Greek may refer to: Greece Anything of, from, or related to Greece Greece ( el, Ελ ...
.
South America South America is a continent A continent is any of several large landmasses. Generally identified by convention (norm), convention rather than any strict criteria, up to seven geographical regions are commonly regarded as continent ...

South America
moved northward to southern Euramerica, while the eastern portion of Gondwana (
India India, officially the Republic of India (Hindi Hindi (Devanagari: , हिंदी, ISO 15919, ISO: ), or more precisely Modern Standard Hindi (Devanagari: , ISO 15919, ISO: ), is an Indo-Aryan language spoken chiefly in Hindi Belt, ...

India
,
Antarctica Antarctica ( or ) is Earth's southernmost continent. It contains the geographic South Pole and is situated in the Antarctic region of the Southern Hemisphere, almost entirely south of the Antarctic Circle, and is surrounded by the Southern Oc ...

Antarctica
, and
Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

Australia
) headed toward the South Pole from the
equator The Equator is a circle of latitude, about in circumference, that divides Earth into the Northern Hemisphere, Northern and Southern Hemisphere, Southern hemispheres. It is an imaginary line located at 0 degrees latitude, halfway between the N ...

equator
. North and South China were on independent continents. The
Kazakhstania Kazakhstania ( kk, Qazaqstaniya), the Kazakh terranes, or the Kazakhstan Block, is a geological region in Central Asia Central Asia is a region in Asia which stretches from the Caspian Sea in the west to China and Mongolia in the east, and from ...
microcontinent had collided with
Siberia Siberia (; rus, Сибирь, r=Sibir', p=sʲɪˈbʲirʲ, a=Ru-Сибирь.ogg) is an extensive geographical region, constituting all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has been a part of R ...
. (Siberia had been a separate continent for millions of years since the deformation of the supercontinent
Pannotia Pannotia (from Greek: ''pan- Pan may refer to: Prefix *''Pan-'', a prefix from the Greek language, Greek πᾶν, ''pan'', meaning "all", "of everything", or "involving all members" of a group ** , most but not all using the prefix People * Pan ...

Pannotia
in the Middle Carboniferous.) The Variscan orogeny raised the Central Pangean Mountains, which were comparable to the modern
Himalayas The Himalayas, or Himalaya (; Sanskrit Sanskrit (; attributively , ; nominalization, nominally , , ) is a classical language of South Asia that belongs to the Indo-Aryan languages, Indo-Aryan branch of the Indo-European languages. It ar ...

Himalayas
in scale. With Pangea now stretching from the South Pole across the equator and well into the Northern Hemisphere, an intense
monsoon A monsoon () is traditionally a seasonal reversing wind accompanied by corresponding changes in precipitation In meteorology Meteorology is a branch of the (which include and ), with a major focus on . The study of meteorology ...
climate was established, except for a perpetually wet zone immediately around the central mountains.


Formation of Laurasia

Western
Kazakhstania Kazakhstania ( kk, Qazaqstaniya), the Kazakh terranes, or the Kazakhstan Block, is a geological region in Central Asia Central Asia is a region in Asia which stretches from the Caspian Sea in the west to China and Mongolia in the east, and from ...
collided with
Baltica Baltica is a paleocontinent A paleocontinent or palaeocontinent is a distinct area of continental crust 350px, The thickness of Crust (geology)#Earth's crust, Earth's crust (km) Continental crust is the layer of Igneous rock, igneous, Sedim ...
in the Late Carboniferous, closing the
Ural Ocean The Ural Ocean (also called the Uralic Ocean) was a small, ancient ocean that was situated between Siberia Siberia (; rus, Сибирь, r=Sibir', p=sʲɪˈbʲirʲ, a=Ru-Сибирь.ogg) is an extensive geographical region spanning much of N ...
between them and the western Proto-Tethys in them (
Uralian orogeny The Uralian orogeny refers to the long series of linear deformation and mountain building events that raised the Ural Mountains The Ural Mountains (; rus, Ура́льские го́ры, r=Uralskiye gory, p=ʊˈralʲskʲɪjə ˈgorɨ; ba, У ...
), causing the formation of not only the
Ural Mountains The Ural Mountains (; rus, Ура́льские го́ры, r=Uralskiye gory, p=ʊˈralʲskʲɪjə ˈgorɨ; ba, Урал тауҙары, ''Ural tauźarı'') or simply the Urals, are a mountain range A mountain range is a series of mounta ...
but also the supercontinent of Laurasia. This was the last step of the formation of Pangaea. Meanwhile, South America had collided with southern
Laurentia Image:North america craton nps.gif, upright=1.4, Laurentia, also called the North American craton Laurentia or the North American Craton is a large continental craton that forms the Geology of North America, ancient geological core of North Ameri ...
, closing the
Rheic Ocean The Rheic Ocean was an ocean The ocean (also the sea or the world ocean) is the body of salt water which covers approximately 71% of the surface of the Earth.world map, originally prepared by Joan Blaeu for his ''Atlas Maior'', published ...
and completing the Variscian orogeny with the formation the southernmost part of the
Appalachians The Appalachian Mountains, often called the Appalachians, are a mountain range, system of mountains in eastern North America. The Appalachians first formed roughly 480 million years ago during the Ordovician, Ordovician Period. They once reache ...
and
Ouachita Mountains The Ouachita Mountains (), simply referred to as the Ouachitas, are a mountain range A mountain range is a series of mountains ranged in a line and connected by high ground. A mountain system or mountain belt is a group of mountain ranges w ...

Ouachita Mountains
. By this time, Gondwana was positioned near the South Pole, and glaciers were forming in Antarctica, India, Australia, southern Africa, and South America. The
North China North China, or Huabei ( ) is a geographical region of China, consisting of the provinces of Beijing Beijing ( ; ; ), Chinese postal romanization, alternatively romanized as Peking ( ), is the Capital city, capital of the People's Rep ...

North China
block collided with
Siberia Siberia (; rus, Сибирь, r=Sibir', p=sʲɪˈbʲirʲ, a=Ru-Сибирь.ogg) is an extensive geographical region, constituting all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has been a part of R ...

Siberia
by
Jurassic The Jurassic ( ) is a geologic period The geologic time scale (GTS) is a system of chronological dating that classifies Geology, geological strata (stratigraphy) in time. It is used by geologists, paleontology, paleontologists, and other earth ...
, completely closing the Proto-Tethys Ocean. By the
Early Permian#REDIRECT One (disambiguation) One or 1 is the first natural number. 1, one, or ONE may also refer to: * AD 1, first year of the AD era * 1 BC, the year before AD 1 * One (pronoun), ''One'' (pronoun), a pronoun in the English language * Hydrogen, ...
, the
Cimmerian plate Cimmeria was an ancient continent, or, rather, a string of microcontinents or terranes, that rifted from Gondwana in the Southern Hemisphere and was accreted to Eurasia in the Northern Hemisphere. It consisted of parts of what is today Turkey, Ira ...
split from
Gondwana Gondwana () or Gondwanaland was a supercontinent In geology Geology (from the Ancient Greek γῆ, ''gē'' ("earth") and -λoγία, ''-logia'', ("study of", "discourse")) is an Earth science concerned with the solid Earth, the rock (ge ...

Gondwana
and headed towards Laurasia, thus closing the
Paleo-Tethys Ocean The Paleo-Tethys or Palaeo-Tethys Ocean was an ocean The ocean (also the or the world ocean) is the body of that covers approximately 70.8% of the surface of and contains 97% of . Another definition is "any of the large bodies of water ...
, but forming a new ocean, the
Tethys Ocean The Tethys Ocean ( el, Τηθύς ''Tēthús''), also called the Tethys Sea or the Neo-Tethys, was an ocean during much of the Era located between the ancient continents of and , before the opening of the and oceans during the Period. Etym ...
, in its southern end. Most of the landmasses were all in one. By the
Triassic The Triassic ( ) is a geologic period The geologic time scale (GTS) is a system of chronological dating that classifies Geology, geological strata (stratigraphy) in time. It is used by geologists, paleontology, paleontologists, and other earth ...

Triassic
Period, Pangaea rotated a little, and the Cimmerian plate was still travelling across the shrinking Paleo-Tethys until the
Middle Jurassic The Middle Jurassic is the second epoch In chronology 222px, Joseph Scaliger's ''De emendatione temporum'' (1583) began the modern science of chronology Chronology (from Latin Latin (, or , ) is a classical language belonging to the It ...
. By the late Triassic, the Paleo-Tethys had closed from west to east, creating the Cimmerian Orogeny. Pangaea, which looked like a ''C'', with the new Tethys Ocean inside the ''C'', had rifted by the Middle Jurassic, and its deformation is explained below. File:Pangaea assembly 1.png, Paleogeography of Earth in the late Cambrian, around 490 Ma File:Pangaea assembly 430.png, Paleogeography of Earth in the middle Silurian, around 430 Ma. Avalonia and Baltica have fused with Laurentia to form Laurussia. File:Pangea assembly 310.png, Paleogeography of Earth in the late Carboniferous, around 310 Ma. Laurussia has fused with Gondwana to form Pangea. File:Pangea assembly 250.png, Paleogeography of the Earth at the Permian-Triassic boundary, around 250 Mya. Siberia has fused with Pangea to complete the assembly of the supercontinent.


Life

Pangaea existed as a supercontinent for 160 million years, from its assembly around 335 million years ago (
Early Carboniferous Early may refer to: History * The beginning or oldest part of a defined historical period, as opposed to middle or late periods, e.g.: ** Early Christianity ** Early modern Europe Places in the United States * Early, Iowa * Early, Texas * Early B ...
) to its breakup 175 million years ago (
Middle Jurassic The Middle Jurassic is the second epoch In chronology 222px, Joseph Scaliger's ''De emendatione temporum'' (1583) began the modern science of chronology Chronology (from Latin Latin (, or , ) is a classical language belonging to the It ...
). During this interval, important developments in the evolution of life took place. The seas of the Early Carboniferous were dominated by rugose corals, brachiopods, bryozoans, sharks, and the first bony fish. Life on land was dominated by lycopsid forests inhabited by insects and other arthropods and the first tetrapods. By the time Pangaea broke up, in the Middle Jurassic, the seas swarmed with molluscs (particularly ammonites), ichthyosaurs, sharks and rays, and the first ray-finned bony fishes, while life on land was dominated by forests of cycads and conifers in which dinosaurs flourished and in which the first true mammals had appeared. The evolution of life in this interval of time reflected conditions created by the assembly of Pangaea. The assembly of most of the continental crust into one landmass reduced the extent of sea coasts. Increased erosion from uplifted continental crust increased the importance of floodplain and delta environments relative to shallow marine environments. Continental assembly and uplift also meant an increasingly arid climate over much of the surface of the Earth. This favored the evolution of amniotes and seed plants, whose eggs and seeds were better adapted to dry climates. The early drying trend was most pronounced in western Pangaea, which became an epicenter for the evolution and geographical spread of amniotes. Coal swamps are typically a feature of perpetually wet regions close to the equator. The assembly of Pangaea disrupted the intertropical convergence zone and created an extreme monsoon climate that reduced the deposition of coal to its lowest level in the last 300 million years. During the Permian, coal deposition was largely restricted to the North and South China microcontinents, which were among the few areas of continental crust that had not joined with Pangaea. The extremes of climate conditions in the interior of Pangaea are reflected in bone growth patterns of pareiasaurs and in the growth patterns in gymnosperm forests. The lack of oceanic barriers is thought to have favored ''cosmopolitanism'', in which species show a wide geographical distribution. Cosmopolitanism was also driven by mass extinctions, including the Permian–Triassic extinction event, the most severe in the fossil record, and also the Triassic–Jurassic extinction event. These events resulted in ''disaster fauna'' showing little diversity and high cosmopolitanism. These include ''
Lystrosaurus ''Lystrosaurus'' (; 'shovel lizard'; proper Greek is λίστρον ''lístron'' ‘tool for leveling or smoothing, shovel, spade, hoe’) is an extinct genus of herbivorous A herbivore is an animal Animals (also called Metazoa) ...

Lystrosaurus
'', which opportunistically spread to every corner of Pangaea following the Permian-Triassic extinction event. On the other hand, there is evidence that many Pangaean species were ''provincial'', with a limited geographical range, in spite of the lack of geographical barriers. This may be due to the strong variations in climate by latitude and season produced by the extreme monsoon climate. For example, cold-adapted pteridosperms (early seed plants) of Gondwana were blocked from spreading throughout Pangaea by the warming climate, and northern pteridosperms ended up dominating Gondwana in the
Triassic The Triassic ( ) is a geologic period The geologic time scale (GTS) is a system of chronological dating that classifies Geology, geological strata (stratigraphy) in time. It is used by geologists, paleontology, paleontologists, and other earth ...

Triassic
.


Mass extinctions

The tectonics and geography of Pangaea may have worsened the Permian-Triassic extinction event or other extinctions. For example, the reduced area of continental shelf environments may have left marine species vulnerable to extinction. However, no evidence for a species-area effect has been found in more recent and better characterized portions of the geologic record. Another possibility is that reduced sea-floor spreading associated with the formation of Pangaea, and the resulting cooling and subsidence of oceanic crust, may have reduced the number of islands that could have served as Refugium (population biology), refugia for marine species. Species diversity may have already been reduced prior to mass extinction events due to mingling of species possible when formerly separate continents were merged. However, there is strong evidence that climate barriers continued to separate ecological communities in different parts of Pangaea. The eruptions of the Emeishan Traps may have eliminated South China, one of the few continental areas not merged with Pangaea, as a refugium.


Rifting and break-up

There were three major phases in the break-up of Pangaea.


Opening of the Atlantic

The first phase began in the Early Jurassic, Early-
Middle Jurassic The Middle Jurassic is the second epoch In chronology 222px, Joseph Scaliger's ''De emendatione temporum'' (1583) began the modern science of chronology Chronology (from Latin Latin (, or , ) is a classical language belonging to the It ...
(about 175 Ma), when Pangaea began to rift from the Tethys Ocean in the east to the Pacific Ocean in the west. The rifting that took place between North America and Africa produced multiple Eastern North America Rift Basins, failed rifts. One rift resulted in a new ocean, the North Atlantic Ocean. The Atlantic Ocean did not open uniformly; rifting began in the north-central Atlantic. The South Atlantic did not open until the Cretaceous when Laurasia started to rotate clockwise and moved northward with North America to the north, and Eurasia to the south. The clockwise motion of Laurasia led much later to the closing of the
Tethys Ocean The Tethys Ocean ( el, Τηθύς ''Tēthús''), also called the Tethys Sea or the Neo-Tethys, was an ocean during much of the Era located between the ancient continents of and , before the opening of the and oceans during the Period. Etym ...
and the widening of the "Sinus Borealis", which later became the Arctic Ocean. Meanwhile, on the other side of Africa and along the adjacent margins of east Africa, Antarctica and Madagascar, new rifts were forming that would lead to the formation of the southwestern Indian Ocean that would open up in the Cretaceous.


Break-up of Gondwana

The second major phase in the break-up of Pangaea began in the Early Cretaceous (150–140 Ma), when the landmass of Gondwana separated into multiple continents (Africa, South America, India, Antarctica, and Australia). The subduction at Tethyan Trench probably caused Africa, India and Australia to move northward, causing the opening of a "South Indian Ocean". In the Early Cretaceous, Atlantica, today's South America and Africa, finally separated from eastern Gondwana (Antarctica, India and Australia). Then in the Middle Cretaceous, Gondwana fragmented to open up the South Atlantic Ocean as South America started to move westward away from Africa. The South Atlantic did not develop uniformly; rather, it rifted from south to north. Also, at the same time, Madagascar and India began to separate from Antarctica and moved northward, opening up the Indian Ocean. Madagascar and India separated from each other 100–90 Ma in the Late Cretaceous. India continued to move northward toward Eurasia at 15 centimeters (6 in) a year (a plate tectonic record), closing the eastern Tethys Ocean, while Madagascar stopped and became locked to the African Plate. New Zealand, New Caledonia and the rest of Zealandia (continent), Zealandia began to separate from Australia, moving eastward toward the Pacific and opening the Coral Sea and Tasman Sea.


Opening of the Norwegian Sea and break-up of Australia and Antarctica

The third major and final phase of the break-up of Pangaea occurred in the early Cenozoic (Paleocene to Oligocene). Laurasia split when North America/Greenland (also called
Laurentia Image:North america craton nps.gif, upright=1.4, Laurentia, also called the North American craton Laurentia or the North American Craton is a large continental craton that forms the Geology of North America, ancient geological core of North Ameri ...
) broke free from Eurasia, opening the Norwegian Sea about 60–55 Ma. The Atlantic and Indian Oceans continued to expand, closing the Tethys Ocean. Meanwhile, Australia split from Antarctica and moved quickly northward, just as India had done more than 40 million years before. Australia is currently on a collision course with eastern Asia. Both Australia and India are currently moving northeast at 5–6 centimeters (2–3 in) a year. Antarctica has been near or at the South Pole since the formation of Pangaea about 280 Ma. India started to collide with Asia beginning about 35 Ma, forming the Himalayan orogeny, and also finally closing the Tethys Ocean, Tethys Seaway; this collision continues today. The African Plate started to change directions, from west to northwest toward Europe, and South America began to move in a northward direction, separating it from Antarctica and allowing complete oceanic circulation around Antarctica for the first time. This motion, together with decreasing atmospheric carbon dioxide concentrations, caused a rapid cooling of Antarctica and allowed glaciers to form. This glaciation eventually coalesced into the kilometers-thick ice sheets seen today. Other major events took place during the Cenozoic, including the opening of the Gulf of California, the uplift of the Alps, and the opening of the Sea of Japan. The break-up of Pangaea continues today in the Red Sea Rift and East African Rift.


Climate change after Pangaea

The breakup of Pangaea was accompanied by outgassing of large quantities of carbon dioxide from continental rifts. This produced a Mesozoic CO2 High that contributed to the very warm climate of the Early Cretaceous. The opening of the
Tethys Ocean The Tethys Ocean ( el, Τηθύς ''Tēthús''), also called the Tethys Sea or the Neo-Tethys, was an ocean during much of the Era located between the ancient continents of and , before the opening of the and oceans during the Period. Etym ...
also contributed to the warming of the climate. The very active mid-ocean ridges associated with the breakup of Pangaea raised sea levels to the highest in the geological record, flooding much of the continents. The expansion of the temperate climate zones that accompanied the breakup of Pangaea may have contributed to the diversification of the angiosperms.


See also

* History of Earth * Potential future supercontinents: Pangaea Ultima, Novopangaea & Amasia (continent), Amasia * Supercontinent cycle * Wilson Cycle


References


External links


USGS Overview




{{Authority control Carboniferous paleogeography Former supercontinents Historical continents Jurassic paleogeography Permian paleogeography Plate tectonics Triassic paleogeography