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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 (geology), rocks of which it is composed, and the proces ...
that formed during the late
Neoproterozoic The Neoproterozoic Era is the unit of geologic time The geologic time scale (GTS) is a system of chronological datingChronological dating, or simply dating, is the process of attributing to an object or event a date in the past, allowing such ob ...
(about 550 million years ago) and began to break up during the
Jurassic The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The J ...
(about 180 million years ago), with the final stages of breakup, including the opening of the
Drake Passage Image:Drake-Passage profile hg.png, Depth profile with salinity and temperature for surface The Drake Passage (referred to as Mar de Hoces Hoces Sea"in Spain and other Spanish speaking countries) is the body of water between South America's ...
separating South America and Antarctica occurring during the
Paleogene The Paleogene ( ; also spelled Palaeogene or Palæogene; informally Lower Tertiary or Early Tertiary) is a geologic period and system that spans 43 million years from the end of the Cretaceous The Cretaceous ( ) is a geological period A geologi ...
. Gondwana was not considered a supercontinent by the earliest definition, since the landmasses of
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 ...
,
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 ...
, and
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 ...
were separated from it. It was formed by 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 ...
of several
craton A craton (, , or ; from el, κράτος ''kratos'' "strength") is an old and stable part of the continental lithosphere, which consists of Earth's two topmost layers, the crust (geology), crust and the uppermost mantle (geology), mantle. Having ...
s. Eventually, Gondwana became the largest piece 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, Sedimentary rock, sedimentary, and metamorphic rocks that forms the geological continents and the areas of shallo ...
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 Hellenic Republic, is a country located in Southeast Europe. Its popula ...
Era, covering an area of about , about one-fifth of the Earth's surface. During the
Carboniferous Period The Carboniferous ( ) is a Period (geology), geologic period and System (stratigraphy), system of the Paleozoic that spans 60 million years from the end of the Devonian Period million years ago (annum, Mya), to the beginning of the Permian Period ...
, it merged with
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 ...
to form a larger supercontinent called
Pangaea Pangaea or Pangea () 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 (geology) ...

Pangaea
. Gondwana (and Pangaea) gradually broke up during the
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 ...
Era. The remnants of Gondwana make up around two-thirds of today's continental area, including
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
,
Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area and 20% of i ...

Africa
,
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
,
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 ...
, the Indian Subcontinent,
Zealandia Zealandia (prounounced ), also known as ( Māori) or Tasmantis, is an almost entirely submerged mass of continental crust 350px, The thickness of Crust (geology)#Earth's crust, Earth's crust (km) Continental crust is the layer of Igneous ...
, and
Arabia The Arabian Peninsula (; ar, شِبْهُ الْجَزِيرَةِ الْعَرَبِيَّة, , "Arabian Peninsula" or , , "Island of the Arabs") is a peninsula of Western Asia, situated northeast of Africa on the Arabian Plate. At , the ...

Arabia
. The formation of Gondwana began   with the
East African Orogeny The East African Orogeny (EAO) is the main stage in the Neoproterozoic The Neoproterozoic Era is the unit of geologic time from 1,000 million to 541 million years ago. It is the last era of the Precambrian Supereon and the Proterozoic Eon; it ...
, the collision of India and Madagascar with East Africa, and was completed with the overlapping Brasiliano and Kuunga orogenies, the collision of South America with Africa, and the addition of Australia and Antarctica, respectively. Regions that were part of Gondwana have shared floral and zoological elements that persist to the present day.


Name

The continent of Gondwana was named by the Austrian scientist
Eduard Suess Eduard Suess (; 20 August 1831 - 26 April 1914) was an Austrian geologist A geologist is a scientist who studies the solid, liquid, and gaseous matter that constitutes the Earth and other terrestrial planets, as well as the processes that sha ...
, after the Gondwana region of central
India India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area, the List of countries and dependencies by population, second-most populous ...

India
which is derived from
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 arose in South Asia after its predecessor langua ...

Sanskrit
for "forest of the
Gonds The Gondi (Gōndi) or Gond or Koitur are a Dravidian Dravidian, Dravidan, or Dravida may refer to: Language and culture *Dravidian languages, a family of languages spoken mainly in South India and northeastern Sri Lanka *Proto-Dravidian langua ...
". The name had been previously used in a geological context, first by H.B. Medlicott in 1872, from which the Gondwana sedimentary sequences (
Permian The Permian ( ) 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 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
) are also described. The term "Gondwanaland" is preferred by some scientists in order to make a clear distinction between the region and the supercontinent.


Formation

The assembly of Gondwana was a protracted process during the Neoproterozoic and Paleozoic, which however remains incompletely understood because of the lack of paleo-magnetic data. Several
orogenies An orogeny is an event that leads to both structural Deformation (physics), deformation and compositional differentiation of the Earth's lithosphere (Crust (geology), crust and uppermost Mantle (geology), mantle) at Convergent boundary, converge ...
, collectively known as the
Pan-African orogeny The Pan-African orogeny was a series of major Neoproterozoic The Neoproterozoic Era is the unit of geologic time from 1,000 million to 541 million years ago. It is the last era of the Precambrian Supereon and the Proterozoic Eon; it is subdivid ...
, led to the amalgamation of most of the continental fragments of a much older 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
. One of those orogenic belts, the
Mozambique Belt The Mozambique Belt is a band in the earth's crust that extends from East Antarctica through East Africa up to the Arabian-Nubian Shield. It formed as a suture (geology), suture between plates during the Pan-African orogeny, when Gondwana was form ...
, formed and was originally interpreted as the suture between East (India, Madagascar, Antarctica, and Australia) and West Gondwana (Africa and South America). Three orogenies were recognized during the 1990s: the
East African Orogeny The East African Orogeny (EAO) is the main stage in the Neoproterozoic The Neoproterozoic Era is the unit of geologic time from 1,000 million to 541 million years ago. It is the last era of the Precambrian Supereon and the Proterozoic Eon; it ...
() and
Kuunga orogeny The Kuunga orogeny (from Swahili, "to unite") was an orogeny An orogeny is an event that leads to both structural deformation and compositional differentiation of the Earth's lithosphere A lithosphere ( grc, wikt:λίθος#Ancient Greek, ...
(including the Malagasy Orogeny in southern Madagascar) (), the collision between East Gondwana and East Africa in two steps, and the
Brasiliano orogeny Brasiliano orogeny or Brasiliano cycle ( pt, Orogênese Brasiliana and ''Ciclo Brasiliano'') refers to a series of orogeny, orogenies of Neoproterozoic, Neoproterozoic age exposed chiefly in Brazil but also in other parts of South America. The Brasi ...
(), the successive collision between South American and African
craton A craton (, , or ; from el, κράτος ''kratos'' "strength") is an old and stable part of the continental lithosphere, which consists of Earth's two topmost layers, the crust (geology), crust and the uppermost mantle (geology), mantle. Having ...
s. The last stages of Gondwanan assembly overlapped with the opening 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 ...
between
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 ...
and western Gondwana. During this interval, the Cambrian explosion occurred. Laurentia was docked against the western shores of a united Gondwana for a short period near the Precambrian/Cambrian boundary, forming the short-lived and still disputed 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
. The Mozambique Ocean separated the
Congo Congo may refer to either of two countries that border the Congo River The Congo River ( kg, Nzâdi Kôngo, french: Fleuve Congo, pt, Rio Congo), formerly also known as the Zaire River, is the second longest river in Africa Africa ...
Tanzania Tanzania (; ), officially the United Republic of Tanzania ( sw, Jamhuri ya Muungano wa Tanzania), is a country in East Africa East Africa or Eastern Africa is the eastern subregion of the Africa Africa is the world's second-larges ...
Bangweulu Block of central Africa from Neoproterozoic India (India, the Antongil Block in far eastern Madagascar, the
Seychelles Seychelles (; ), officially the Republic of Seychelles (french: link=no, République des Seychelles; Creole: ''La Repiblik Sesel''), is an archipelagic island country An island country or an island nation is a country A country ...

Seychelles
, and the Napier and Rayner Complexes in
East Antarctica Image of a variety of ice types off the coast of East Antarctica. East Antarctica, also called Greater Antarctica, constitutes the majority (two-thirds) of the Antarctica, Antarctic continent, lying on the Indian Ocean side of the continent, se ...
). The
Azania Azania ( grc, Ἀζανία) is a name that has been applied to various parts of southeastern tropical Africa. In the Roman Empire, Roman period and perhaps earlier, the toponym referred to a portion of the Southeast Africa coast extending from no ...
continent (much of central
Madagascar Madagascar (; mg, Madagasikara), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), and previously known as the Malagasy Republic The Malagasy Republic ( mg, Repoblika Mal ...

Madagascar
, the
Horn of Africa The Horn of Africa (HoA), also known as the Somali Peninsula, is a large peninsula of East Africa.Robert Stock, ''Africa South of the Sahara, Second Edition: A Geographical Interpretation'', (The Guilford Press; 2004), p. 26 Located on the ea ...

Horn of Africa
and parts of
Yemen ) , image_map = Yemen on the globe (Yemen centered).svg , map_caption = , image_map2 = , capital = Sana'a Sanaa ( ar, صَنْعَاء, ' , Yemeni Arabic: ; Old South Arabian: 𐩮 ...

Yemen
and Arabia) was an island in the Mozambique Ocean. The continent Australia/ Mawson was still separated from India, eastern Africa, and Kalahari by , when most of western Gondwana had already been amalgamated. By 550 Ma, India had reached its Gondwanan position, which initiated the Kuunga orogeny (also known as the Pinjarra orogeny). Meanwhile, on the other side of the newly forming Africa, Kalahari collided with Congo and Rio de la Plata which closed the Adamastor Ocean. 540–530 Ma, the closure of the Mozambique Ocean brought India next to Australia–East Antarctica, and both North and South China were located in proximity to Australia. As the rest of Gondwana formed, a complex series of orogenic events assembled the eastern parts of Gondwana (eastern Africa, Arabian-Nubian Shield, Seychelles, Madagascar, India, Sri Lanka, East Antarctica, and Australia) . First the Arabian-Nubian Shield collided with eastern Africa (in the Kenya-Tanzania region) in the
East African Orogeny The East African Orogeny (EAO) is the main stage in the Neoproterozoic The Neoproterozoic Era is the unit of geologic time from 1,000 million to 541 million years ago. It is the last era of the Precambrian Supereon and the Proterozoic Eon; it ...
. Then Australia and East Antarctica were merged with the remaining Gondwana in the
Kuunga Orogeny The Kuunga orogeny (from Swahili, "to unite") was an orogeny An orogeny is an event that leads to both structural deformation and compositional differentiation of the Earth's lithosphere A lithosphere ( grc, wikt:λίθος#Ancient Greek, ...
. The later Malagasy orogeny at about 550–515 Mya affected Madagascar, eastern East Africa and southern India. In it, Neoproterozoic India collided with the already combined Azania and Congo–Tanzania–Bangweulu Block, suturing along the
Mozambique Belt The Mozambique Belt is a band in the earth's crust that extends from East Antarctica through East Africa up to the Arabian-Nubian Shield. It formed as a suture (geology), suture between plates during the Pan-African orogeny, when Gondwana was form ...
. The
Terra Australis Orogen The Terra Australis Orogen (TAO) was the oceanic southern margin of Gondwana which stretched from South America to Eastern Australia and encompassed South Africa, West Antarctica, New Zealand and Victoria Land in East Antarctica. Origins Terra ...
developed along Gondwana's western, southern, and eastern margins. Proto-Gondwanan Cambrian arc belts from this margin have been found in eastern Australia, Tasmania, New Zealand, and Antarctica. Though these belts formed a continuous arc chain, the direction of subduction was different between the Australian-Tasmanian and New Zealand-Antarctica arc segments.


Peri-Gondwana development: Paleozoic rifts and accretions

A large number of terranes were accreted to Eurasia during Gondwana's existence but the Cambrian or Precambrian origin of many of these terranes remains uncertain. For example, some Palaeozoic terranes and microcontinents that now make up Central Asia, often called the "Kazakh" and "Mongolian terranes", were progressively amalgamated into the continent
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 ...
in the Late Silurian. Whether these blocks originated on the shores of Gondwana is not known. In the Early Palaeozoic the
Armorican terrane The Armorican terrane, Armorican terrane assemblage, or simply Armorica, was a Continental fragment, microcontinent or group of continental fragments that rifted away from Gondwana towards the end of the Silurian and collided with Euramerica, Lau ...
, which today form large parts of France, was part of either Peri-Gondwana or core Gondwana; the Rheic Ocean closed in front of it and the Palaeo-Tethys Ocean opened behind it. Precambrian rocks from the
Iberian Peninsula The Iberian Peninsula , ** * Aragonese Aragonese or Aragones may refer to: * Something related to Aragon, an autonomous community and former kingdom in Spain * the Aragonese people, those originating from or living in the historical region ...

Iberian Peninsula
suggest it too probably formed part of core Gondwana before its detachment as an
oroclineAn orocline — from the Greek words for "mountain" and "to bend" — is a bend or curvature of an orogenic (mountain building) belt imposed after it was formed. The term was introduced by S. Warren Carey in 1955 in a paper setting forth how complex ...
in 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 ...
close to the Carboniferous–Permian boundary. South-east Asia is made of Gondwanan and
Cathaysia Cathaysia was a microcontinent Continental crustal fragments, partially synonymous with microcontinents, are pieces of continent A continent is one of several large landmasses. Generally identified by convention (norm), convention rather ...
n continental fragments that were assembled during the Mid-Palaeozoic and Cenozoic. This process can be divided into three phases of rifting along Gondwana's northern margin: firstly, in the Devonian,
North North is one of the four compass points The points of the compass are the vectors by which planet A planet is an astronomical body orbiting a star or Stellar evolution#Stellar remnants, stellar remnant that is massive enough to be Hydro ...
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 ...
, together with
TarimTarim may refer to: *Tarim, Yemen, a city in Yemen *Tarim District, Yemen *Tarim River, China *Tarim Basin, China ** Tarim Mummies, a series of mummies which have been excavated at Niya, an oasis in the Tarim Basin *Tarim, the monotheistic god worsh ...
and
Quidam ''Quidam'' ( ) was the ninth stage show produced by Cirque du Soleil. It premiered in April 1996 and has been watched by millions of spectators around the world. ''Quidam'' originated as a big-top show in Montreal and was converted into an arena ...
(north-western China) rifted, opening the Palaeo-Tethys behind them. These terranes accreted to Asia during Late Devonian and Permian. Secondly, in the Late Carboniferous to Early Permian, Cimmerian terranes opened Meso-Tethys Ocean; Sibumasu and
Qiangtang The Changtang (alternatively spelled Changthang or Qangtang) is a part of the high altitude Tibetan Plateau The Tibetan Plateau (), also known in China as the Qinghai–Tibet Plateau or the Qing–Zang Plateau () or as the Himalayan Plateau in In ...
were added to south-east Asia during
Late Permian Late may refer to: * LATE, an acronym which could stand for: ** Limbic-predominant age-related TDP-43 encephalopathy, a proposed form of dementia ** Local-authority trading enterprise, a New Zealand business law ** Local average treatment effect, ...
and Early Jurassic. Thirdly, in the Late Triassic to Late Jurassic,
Lhasa Lhasa (; Lhasa dialect: ; bo, text=ལྷ་ས, translation=Place of Gods) is the urban center of the prefecture-level city, prefecture-level Lhasa (prefecture-level city), Lhasa City and the administrative capital of Tibet. The inner urban ...
, West Burma, Woyla terranes opened the Neo-Tethys Ocean; Lhasa collided with Asia during the Early Cretaceous, and West Burma and Woyla during the Late Cretaceous. Gondwana's long, northern margin had remained a mostly passive margin throughout the Palaeozoic. The Early Permian opening of the Neo-Tethys Ocean along this margin produced a long series of terranes, many of which were and still are being deformed in the Himalaya Orogeny. From Turkey to north-eastern India: the Taurides in southern Turkey; the Lesser Caucasus Terrane in Georgia; the Sanand, Alborz, and Lut terranes in Iran; the Mangysglak or Kopetdag Terrane in the Caspian Sea; the Afghan Terrane; the Karakorum Terrane in northern Pakistan; and the Lhasa and Qiangtang terranes in Tibet. The Permian–Triassic widening of the Neo-Tethys pushed all these terranes across the Equator and over to Eurasia.


Southwestern accretions

During the Neoproterozoic to Palaeozoic phase of the
Terra Australis Orogen The Terra Australis Orogen (TAO) was the oceanic southern margin of Gondwana which stretched from South America to Eastern Australia and encompassed South Africa, West Antarctica, New Zealand and Victoria Land in East Antarctica. Origins Terra ...
a series of terranes were rafted from the proto-Andean margin when the Iapteus Ocean opened, to be added back to Gondwana during the closure of that ocean. During the paleozoic some blocks which helped to form parts of the
Southern Cone The Southern Cone ( es, Cono Sur, pt, Cone Sul) is a geographical and cultural subregion composed of the southernmost areas of South America South America is a continent A continent is any of several large landmasses. Genera ...
of South America, include a piece transferred from Laurentia when the west edge of Gondwana scraped against southeast Laurentia in the
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
. This is the Cuyania or Precordillera
terrane In geology Geology (from the γῆ, ''gē'' ("earth") and -λoγία, ''-logia'', ("study of", "discourse")) is a branch of concerned with both the liquid and , the of which it is composed, and the processes by which they change over time ...
of the
Famatinian orogeny The Famatinian orogeny ( es, Orogenia de Famatina) is an orogeny that predates the Andean orogeny, rise of the Andes and that took place in what is now western South America during the Paleozoic, leading to the formation of the Famatinian orogen al ...
in northwest Argentina which may have continued the line 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 ...
southwards. Chilenia terrane accreted later against Cuyania. The collision of the Patagonian terrane with the southwestern Gondwanan occurred in the late Paleozoic. Subduction-related igneous rocks from beneath the
North Patagonian Massif The North Patagonian Massif or Somún Cura Massif (Spanish language, Spanish: ''Macizo Norpatagónico'', ''Macizo Nordpatagónico'' or ''Macizo de Somún Cura'') is a massif in northern Patagonia located in the Argentine provinces of Río Negro Prov ...
have been dated at 320–330 million years old, indicating that the subduction process initiated in the early Carboniferous. This was relatively short lived (lasting about 20 million years), and initial contact of the two landmasses occurred in the mid-Carboniferous, with broader collision during the early Permian. In the Devonian an
island arc Island arcs are long chains of active volcano A volcano is a rupture in the crust of a planetary-mass object A planet is an astronomical body orbit In physics, an orbit is the gravitationally curved trajectory of an physical b ...

island arc
named Chaitenia accreted to Patagonia in what is now south-central Chile.


Gondwana as part of Pangaea: Late Paleozoic to Early Mesozoic

Gondwana and
Laurasia Laurasia () was the more northern of two large landmasses that formed part of the Pangaea Pangaea or Pangea () was a supercontinent In geology Geology (from the Ancient Greek γῆ, ''gē'' ("earth") and -λoγία, ''-logia'', ("s ...
formed the Pangaea supercontinent during the Carboniferous. Pangaea began to break up in the Mid-Jurassic when the Central Atlantic opened. In the western end of Pangaea, the collision between Gondwana and Laurasia closed the Rheic and Palaeo-Tethys oceans. The obliquity of this closure resulted in the docking of some northern terranes in the
Marathon The marathon is a long-distance foot race with a distance of , usually run as a road running, road race, but the distance can be covered on trail routes. The marathon can be completed by running or with a run/walk strategy. There are also ...
,
OuachitaOuachita may refer to: Places In the United States: * Ouachita, Arkansas, an unincorporated community * Ouachita City, Louisiana, an unincorporated community * The Ouachita Mountains in Arkansas and Oklahoma * The Ouachita orogeny, the geologic eve ...
, Alleghanian, and Variscan orogenies, respectively. Southern terranes, such as and
Oaxaca Oaxaca ( , also , , from nci, Huāxyacac ), officially the Free and Sovereign State of Oaxaca ( es, Estado Libre y Soberano de Oaxaca), is one of the 32 states that compose the political divisions of Mexico, Federative Entities of Mexico. It is ...
, on the other hand, remained largely unaffected by the collision along the southern shores of Laurentia. Some Peri-Gondwanan terranes, such as
Yucatán Yucatán (, also , , ; yua, Yúukatan ), officially the Free and Sovereign State of Yucatán,; yua, link=no, Xóot' Noj Lu'umil Yúukatan. is one of the 32 states which comprise the Federal Entities of Mexico Mexico, officially the Un ...

Yucatán
and
Florida Florida is a U.S. state, state located in the Southeastern United States, Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia (U.S. state), Geor ...

Florida
, were buffered from collisions by major promontories. Other terranes, such as Carolina and Meguma, were directly involved in the collision. The final collision resulted in the Variscan-
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
, stretching from present-day Mexico to southern Europe. Meanwhile,
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 ...
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 ...
and
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 ...
which resulted in the
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 ...
and
Laurasia Laurasia () was the more northern of two large landmasses that formed part of the Pangaea Pangaea or Pangea () was a supercontinent In geology Geology (from the Ancient Greek γῆ, ''gē'' ("earth") and -λoγία, ''-logia'', ("s ...
. Pangaea was finally amalgamated in the Late Carboniferous-Early Permian, but the oblique forces continued until Pangaea began to rift in the Triassic. In the eastern end collisions occurred slightly later. 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
,
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 ...
, and
Indochina Mainland Southeast Asia, also known as the Indochinese Peninsula or Indochina, is the continental portion of Southeast Asia Southeast Asia, also spelled South East Asia and South-East Asia, and also known as Southeastern Asia or SEA, is t ...
blocks rifted from Gondwana during the middle Paleozoic and opened the Proto-Tethys Ocean. North China docked with Mongolia and Siberia during the Carboniferous–Permian, followed by South China. The
Cimmerian The Cimmerians (also Kimmerians; Greek: , ''Kimmérioi'') were a nomadic Indo-European people, who appeared about 1000 BC and are mentioned later in 8th century BC in Assyrian records. While the Cimmerians were often described by contempo ...
blocks then rifted from Gondwana to form the Palaeo-Thethys and Neo-Tethys oceans in the Late Carboniferous, and docked with Asia during the Triassic and Jurassic. Western Pangaea began to rift while the eastern end was still being assembled. The formation of Pangaea and its mountains had a tremendous impact on global climate and sea levels, which resulted in glaciations and continent-wide sedimentation. In North America, the base of the Absaroka sequence coincides with the Alleghanian and Ouachita orogenies and are indicative of a large-scale change in the mode of deposition far away from the Pangaean orogenies. Ultimately, these changes contributed to the
Permian–Triassic extinction event The Permian–Triassic extinction event, also known as the P–Tr extinction, the P–T extinction, the End-Permian Extinction, and colloquially as the Great Dying, formed the boundary between the Permian The Permian ( ) is a geologic period ...
and left large deposits of hydrocarbons, coal, evaporite, and metals. The break-up of Pangaea began with the
Central Atlantic magmatic province The Central Atlantic magmatic province (CAMP) is the Earth's largest continental large igneous province Image:Flood_Basalt_Map.jpg, 300px, Only a few of the largest large igneous provinces appear (coloured dark purple) on this geological map, wh ...
(CAMP) between South America, Africa, North America, and Europe. CAMP covered more than seven million square kilometres over a few million years, reached its peak at , and coincided with the
Triassic–Jurassic extinction event The Triassic–Jurassic (Tr-J) extinction event, sometimes called the end-Triassic extinction, marks the boundary between the Triassic The Triassic ( ) is a geologic period A geological period is one of the several subdivisions of geologic time ...
. The reformed Gondwanan continent was not precisely the same as that which had existed before Pangaea formed; for example, most of
Florida Florida is a U.S. state, state located in the Southeastern United States, Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia (U.S. state), Geor ...

Florida
and southern
Georgia Georgia usually refers to: * Georgia (country) Georgia (, ; ) is a country located at the intersection of Eastern Europe and Western Asia. It is a part of the Caucasus region, bounded to the west by the Black Sea, to the north and east by ...
and
Alabama (We dare defend our rights) , anthem = "Alabama (We dare defend our rights) , anthem = "Alabama (state song), Alabama" , image_map = Alabama in United States.svg , seat ...

Alabama
is underlain by rocks that were originally part of Gondwana, but this region stayed attached to North America when the .


Break-up


Mesozoic

Antarctica, the centre of the supercontinent, shared boundaries with all other Gondwana continents and the fragmentation of Gondwana propagated clockwise around it. The break-up was the result of the eruption of the Karoo-Ferrar, Karoo-Ferrar igneous province, one of the Earth's most extensive large igneous provinces (LIP) , but the oldest Magnetic anomaly, magnetic anomalies between South America, Africa, and Antarctica are found in what is now the southern Weddell Sea where initial break-up occurred during the Jurassic .


Opening of western Indian Ocean

Gondwana began to break up in the early
Jurassic The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The J ...
following the extensive and fast emplacement of the Karoo-Ferrar flood basalts . Before the Karoo plume initiated rifting between Africa and Antarctica, it separated a series of smaller continental blocks from Gondwana's southern, Proto-Pacific margin (along what is now the Transantarctic Mountains): the Antarctic Peninsula, Marie Byrd Land,
Zealandia Zealandia (prounounced ), also known as ( Māori) or Tasmantis, is an almost entirely submerged mass of continental crust 350px, The thickness of Crust (geology)#Earth's crust, Earth's crust (km) Continental crust is the layer of Igneous ...
, and Thurston Island; the Falkland Islands and Ellsworth–Whitmore Mountains (in Antarctica) were rotated 90° in opposite directions; and South America south of the Gastre Fault (often referred to as Tectonic evolution of Patagonia, Patagonia) was pushed westward. The history of the Africa-Antarctica break-up can be studied in great detail in the fracture zones and magnetic anomalies flanking the Southwest Indian Ridge. The Madagascar block and the Mascarene Plateau, stretching from the
Seychelles Seychelles (; ), officially the Republic of Seychelles (french: link=no, République des Seychelles; Creole: ''La Repiblik Sesel''), is an archipelagic island country An island country or an island nation is a country A country ...

Seychelles
to Réunion, were broken off India; elements of this breakup nearly coincide with the Cretaceous–Paleogene extinction event. The India–Madagascar–Seychelles separations appear to coincide with the eruption of the Deccan Traps, Deccan basalts, whose eruption site may survive as the Réunion hotspot. The Seychelles and the Maldives are now separated by the Central Indian Ridge. During the initial break-up in the Early Jurassic a transgression (geology), marine transgression swept over the
Horn of Africa The Horn of Africa (HoA), also known as the Somali Peninsula, is a large peninsula of East Africa.Robert Stock, ''Africa South of the Sahara, Second Edition: A Geographical Interpretation'', (The Guilford Press; 2004), p. 26 Located on the ea ...

Horn of Africa
covering Triassic planation surfaces with sandstone, limestone, shale, marls and evaporites.


Opening of eastern Indian Ocean

East Gondwana, comprising Antarctica, Madagascar, India, and Australia, began to separate from Africa. East Gondwana then began to break up when India moved northwest from Australia-Antarctica. The Indian Plate and the Australian Plate are now separated by the Capricorn Plate and its diffuse boundaries. During the opening of the Indian Ocean, the Kerguelen hotspot first formed the Kerguelen Plateau on the Antarctic Plate and then the Ninety East Ridge on the Indian Plate at . The Kerguelen Plateau and the Broken Ridge, the southern end of the Ninety East Ridge, are now separated by the Southeast Indian Ridge. Separation between Australia and
East Antarctica Image of a variety of ice types off the coast of East Antarctica. East Antarctica, also called Greater Antarctica, constitutes the majority (two-thirds) of the Antarctica, Antarctic continent, lying on the Indian Ocean side of the continent, se ...
began with sea-floor spreading occurring . A shallow seaway developed over the South Tasman Rise during the Early Cenozoic and as oceanic crust started to separate the continents during the Eocene global ocean temperature dropped significantly. A dramatic shift from arc- to rift magmatism separated
Zealandia Zealandia (prounounced ), also known as ( Māori) or Tasmantis, is an almost entirely submerged mass of continental crust 350px, The thickness of Crust (geology)#Earth's crust, Earth's crust (km) Continental crust is the layer of Igneous ...
, including New Zealand, the Campbell Plateau, Chatham Rise, Lord Howe Rise, Norfolk Ridge, and New Caledonia, from West Antarctica .


Opening of South Atlantic Ocean

The Atlantic Ocean#South Atlantic, opening of the South Atlantic Ocean divided West Gondwana (South America and Africa), but there is a considerable debate over the exact timing of this break-up. Rifting propagated from south to north along Triassic–Early Jurassic lineaments, but intra-continental rifts also began to develop within both continents in Jurassic–Cretaceous sedimentary basins; subdividing each continent into three sub-plates. Rifting began at Falkland latitudes, forcing Patagonia to move relative to the still static remainder of South America and Africa, and this westward movement lasted until the Early Cretaceous . From there rifting propagated northward during the Late Jurassic or Early Cretaceous most likely forcing dextral movements between sub-plates on either side. South of the Walvis Ridge and Rio Grande Rise the Paraná and Etendeka traps, Paraná and Etendeka magmatics resulted in further ocean-floor spreading and the development of rifts systems on both continents, including the West and Central African Rift System, Central African Rift System and the Central African Shear Zone which lasted until . At Brazilian latitudes spreading is more difficult to assess because of the lack of palaeo-magnetic data, but rifting occurred in Nigeria at the Benue Trough . North of the Equator the rifting began after and continued until .


Early Andean orogeny

The first phases of Andean orogeny in the
Jurassic The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The J ...
and Early Cretaceous were characterized by extensional tectonics, rifting, the development of back-arc basins and the emplacement of large batholiths. This development is presumed to have been linked to the subduction of cold oceanic crust, oceanic lithosphere. During the mid to Late Cretaceous (ca. 90 million years ago) the Andean orogeny changed significantly in character. Warmer and younger oceanic lithosphere is believed to have started to be subducted beneath South America around this time. Such kind of subduction is held responsible not only for the intense contractional Deformation (engineering), deformation that different lithologies were subject to, but also the mountain building, uplift and erosion known to have occurred from the Late Cretaceous onward. Plate tectonics, Plate tectonic reorganization since the mid-Cretaceous might also have been linked to the rift, opening of the South Atlantic Ocean. Another change related to mid-Cretaceous plate tectonic changes was the change of subduction direction of the oceanic lithosphere that went from having south-east motion to having a north-east motion at about 90 million years ago. While subduction direction changed it remained oblique (and not perpendicular) to the coast of South America, and the direction change affected several subduction, subduction zone-parallel faults including Atacama Fault, Atacama, Domeyko Fault, Domeyko and Liquiñe-Ofqui Fault, Liquiñe-Ofqui.


Cenozoic

The Indian subcontinent began to collide with Asia circa , since which more than of crust has been absorbed by the Himalayas, Himalayan-Tibetan orogen. During the Cenozoic the orogen resulted in the construction of the Tibetan Plateau between the Tethyan Himalayas in the south and the Kunlun Mountains, Kunlun and Qilian Mountains, Qilian mountains in the north. Later, South America was connected to North America via the Isthmus of Panama, cutting off a circulation of warm water and thereby making the Arctic colder, as well as allowing the Great American Interchange. The breakup of Gondwana can be said to continue in eastern Africa at the Afar Triple Junction, which separates the Arabian Plate, Arabian, Nubian Plate, Nubian, and Somali Plate, Somali plates, resulting in rifting in the Red Sea and East African Rift.


Australia–Antarctica separation

In the Early Cenozoic Australia was still connected to Antarctica 35–40° south of its current location and both continents were largely unglaciated. A rift between the two developed but remained an embayment until the Eocene-Oligocene boundary when the Circumpolar Current developed and the glaciation of Antarctica began. Australia was warm and wet during the Palaeocene and dominated by rainforest. The opening of the Tasman Gateway at the Eocene-Oligocene boundary () resulted in abrupt cooling but the Oligocene became a period of high rainfall with swamps in southeast Australia. During the Miocene a warm and humid climate developed with pockets of rainforests in central Australia but before the end of the period colder and drier climate severely reduced this rainforest. A brief period of increased rainfall in the Pliocene was followed by drier climate which favoured grassland. Since then the fluctuation between wet interglacial periods and dry glacial periods has developed into the present arid regime. Australia has thus experienced various climate changes over a 15 million year period with a gradual decrease in precipitation. The Tasman Gateway between Australia and Antarctica began to open . Palaeontological evidences indicate the Antarctic Circumpolar Current (ACC) was established in the Late Oligocene with the full opening of the
Drake Passage Image:Drake-Passage profile hg.png, Depth profile with salinity and temperature for surface The Drake Passage (referred to as Mar de Hoces Hoces Sea"in Spain and other Spanish speaking countries) is the body of water between South America's ...
and the deepening of the Tasman Gateway. The oldest oceanic crust in the Drake Passage, however, is -old which indicates spreading between the Antarctic and South American plates began near the Eocene/Oligocene boundary. Deep sea environments in Tierra del Fuego and the North Scotia Ridge during the Eocene and Oligocene indicate a "Proto-ACC" opened during this period. Later, , a series of events severally restricted the Proto-ACC: change to shallow marine conditions along the North Scotia Ridge; closure of the Fuegan Seaway, the deep sea that existed in Tierra del Fuego; and uplift of the Patagonian Cordillera. This, together with the reactivated Iceland plume, contributed to global warming. During the Miocene, the Drake Passage began to widen and as water flow between South America and the Antarctic Peninsula increased, the renewed ACC resulted in cooler global climate. Since the Eocene the northward movement of the Australian Plate has resulted in an arc-continent collision with the Philippine Sea Plate, Philippine and Caroline Plate, Caroline plates and the uplift of the New Guinea Highlands. From the Oligocene to the late Miocene, the climate in Australia, dominated by warm and humid rainforests before this collision, began to alternate between open forest and rainforest before the continent became the arid or semiarid landscape it is today.


Biogeography

The adjective "Gondwanan" is in common use in biogeography when referring to patterns of distribution of living organisms, typically when the organisms are restricted to two or more of the now-discontinuous regions that were once part of Gondwana, including the Antarctic flora. For example, the plant family Proteaceae, known from all continents in the Southern Hemisphere, has a "Gondwanan distribution" and is often described as an archaic, or relict, lineage. The distributions in the Proteaceae is, nevertheless, the result of both Gondwanan rafting and later oceanic dispersal.


Post-Cambrian diversification

During the Silurian Gondwana extended from the Equator (Australia) to the South Pole (North Africa and South America) whilst Laurasia was located on the Equator opposite to Australia. A short-lived Late Ordovician glaciation was followed by a Silurian Greenhouse and icehouse Earth, Hot House period. The Ordovician–Silurian extinction events, End-Ordovician extinction, which resulted in 27% of marine invertebrate families and 57% of genera going extinct, occurred during this shift from Ice House to Hot House. By the end of the Ordovician ''Cooksonia'', a slender, ground-covering plant, became the first vascular plant to establish itself on land. This first colonisation occurred exclusively around the Equator on landmasses then limited to Laurasia and, in Gondwana, to Australia. In the Late Silurian two distinctive linages, zosterophylls and Rhyniopsida, rhyniophytes, had colonised the tropics. The former evolved into the Lycopodiopsida, lycopods, that were to dominate the Gondwanan vegetation over a long period, whilst the latter evolved into Equisetum, horsetails and gymnosperms. Most of Gondwana was located far from the Equator during this period and remained a lifeless and barren landscape. West Gondwana drifted north during the Devonian which brought Gondwana and Laurasia close together. Global cooling contributed to the Late Devonian extinction (19% of marine families and 50% of genera went extinct) and glaciation occurred in South America. Before Pangaea had formed terrestrial plants, such as pteridophytes, began to diversify rapidly resulting in the colonisation of Gondwana. The Baragwanathia Flora, found only in the Yea Flora Fossil Site, Yea Beds of Victoria, Australia, occurs in two strata separated by or 30 Ma; the upper assemblage is more diverse and includes Baragwanathia, the first primitive herbaceous lycopod to evolve from the zosterophylls. During the Devonian Lepidodendron, giant club mosses replaced the Baragwanathia Flora, introducing the first trees, and by the Late Devonian this first forest was accompanied by the progymnosperms, including the first large trees ''Archaeopteris''. The Late Devonian extinction probably also resulted in Osteolepiformes, osteolepiform fishes Evolution of tetrapods, evolving into the amphibian tetrapods, the earliest land vertebrates, in Greenland and Russia. The only traces of this evolution in Gondwana are amphibian footprints and a single jaw from Australia. The closure of the Rheic Ocean and the formation of Pangaea in the Carboniferous resulted in the rerouting of ocean currents which initiated an Ice House period. As Gondwana began to rotate clockwise, Australia shifted south to more temperate latitudes. An ice cap initially covered most of southern Africa and South America but began to spread to eventually cover most of the supercontinent, save for northernmost Africa-South America and eastern Australia. Giant lycopod and horsetail forests continued to evolve in tropical Laurasia together with a diversified assemblage of true insects. In Gondwana, in contrast, ice and, in Australia, volcanism decimated the Devonian flora to a low-diversity seed fern flora – the pteridophytes were increasingly replaced by the gymnosperms which were to dominate until the Mid-Cretaceous. Australia, however, was still located near the Equator during the Early Carboniferous and during this period Temnospondyli, temnospondyl and Lepospondyli, lepospondyl amphibians and the first amniote reptilians evolved, all closely related to the Laurasian fauna, but spreading ice eventually drove these animals away from Gondwana entirely. The Gondwana ice sheet melted and sea levels dropped during the Permian and Triassic global warming. During this period, the extinct Glossopteridales, glossopterids colonised Gondwana and reached peak diversity in the Late Permian when coal-forming forests covered much of Gondwana. The period also saw the evolution of Voltziales; one of the few plant orders to survive the Permian–Triassic extinction event, end-Permian extinction (57% of marine families and 83% of genera went extinct) which came to dominate in the Late Permian and from whom true conifers evolved. Tall lycopods and Equisetopsida, horsetails dominated the wetlands of Gondwana in the Early Permian. Insects co-evolved with glossopterids across Gondwana and diversified with more than 200 species in 21 orders by the Late Permian, many known from South Africa and Australia. Beetles and cockroaches remained minor elements in this fauna. Tetrapod fossils from the Early Permian have only been found in Laurasia but they became common in Gondwana later during the Permian. The arrival of the therapsids resulted in the first plant-vertebrate-insect ecosystem.


Modern diversification

During the Mid- to Late Triassic, hot house conditions coincided with a peak in biodiversity — the end-Permian extinction was enormous and so was the radiation that followed. Two families of conifers, Podocarpaceae and Araucariaceae, dominated Gondwana in the Early Triassic, but ''Dicroidium'', an extinct genus of fork-leaved seed ferns, dominated woodlands and forests of Gondwana during most of the Triassic. Conifers evolved and radiated during the period, with six of eight extant families already present before the end of it. Bennettitales and Pentoxylales, two now extinct orders of gymnospermous plants, evolved in the Late Triassic and became important in the Jurassic and Cretaceous. It is possible that gymnosperm biodiversity surpassed later angiosperm biodiversity and that the evolution of angiosperms began during the Triassic but, if so, in Laurasia rather than in Gondwana. Two Gondwanan classes, Lycopodiophyta, lycophytes and Equisetopsida, sphenophytes, saw a gradual decline during the Triassic while ferns, though never dominant, managed to diversify. The brief period of ice house conditions during the
Triassic–Jurassic extinction event The Triassic–Jurassic (Tr-J) extinction event, sometimes called the end-Triassic extinction, marks the boundary between the Triassic The Triassic ( ) is a geologic period A geological period is one of the several subdivisions of geologic time ...
had a dramatic impact on dinosaurs but left plants largely unaffected. The Jurassic was mostly one of hot house conditions and, while vertebrates managed to diversify in this environment, plants have left little evidence of such development, with the exception of Cheirolepidiaceae, Cheiroleidiacean conifers and Caytoniales and other groups of seed ferns. In terms of biomass, the Jurassic flora was dominated by conifer families and other gymnosperms that had evolved during the Triassic. The Pteridophytes, that had dominated during the Palaeozoic, were now marginalised, except for ferns. In contrast to Laurentia, very few insect fossils have been found in Gondwana, to a large extent because of widespread deserts and volcanism. While plants had a cosmopolitan distribution, dinosaurs evolved and diversified in a pattern that reflects the Jurassic break-up of Pangaea. The Cretaceous saw the arrival of the angiosperms, or flowering plants, a group that probably evolved in western Gondwana (South America-Africa). From there the angiosperms diversified in two stages: the Monocotyledon, monocots and magnoliids evolved in the Early Cretaceous, followed by the Hamamelidaceae, hammamelid Dicotyledon, dicots. By the Mid-Cretaceous, angiosperms constituted half of the flora in northeastern Australia. There is, however, no obvious connection between this spectacular angiosperm radiation and any known extinction event nor with vertebrate/insect evolution. Insect orders associated with pollination, such as beetles, Fly, flies, Lepidoptera, butterflies and moths, and Hymenoptera, wasps, bees, and ants, radiated continuously from the Permian-Triassic, long before the arrival of the angiosperms. Well-preserved insect fossils have been found in the lake deposits of the Santana Formation in Brazil, the Koonwarra, Victoria#Koonwarra fossil bed, Koonwarra Lake fauna in Australia, and the Orapa diamond mine in Botswana. Dinosaurs continued to prosper but, as the angiosperm diversified, conifers, bennettitaleans and pentoxylaleans disappeared from Gondwana 115 Ma together with the specialised herbivorous ornithischians, whilst generalist browsers, such as several families of Sauropodomorpha, sauropodomorph Saurischia, prevailed. The Cretaceous–Paleogene extinction event killed off all dinosaurs except birds, but plant evolution in Gondwana was hardly affected. Gondwanatheria is an extinct group of non-therian mammals with a Gondwanan distribution (South America, Africa, Madagascar, India, Zealandia and Antarctica) during the Late Cretaceous and Palaeogene. Xenarthra and Afrotheria, two placental clades, are of Gondwanan origin and probably began to evolve separately when Africa and South America separated. The laurel forests of Australia, New Caledonia, and New Zealand have a number of species related to those of the laurissilva of Valdivia, through the connection of the Antarctic flora. These include gymnosperms and the deciduous species of ''Nothofagus'', as well as the New Zealand laurel, ''Corynocarpus laevigatus'', and ''Laurelia novae-zelandiae''. New Caledonia and New Zealand became separated from Australia by continental drift 85 million years ago. The islands still retain plants that originated in Gondwana and spread to the Southern Hemisphere continents later.


See also

* Continental drift, the movement of the Earth's continents relative to each other * Australasian realm * Gondwana Rainforests of Australia * The Great Escarpment, Southern Africa, Great Escarpment of Southern Africa * Plate tectonics, a theory which describes the large-scale motions of Earth's lithosphere * South Polar dinosaurs, which proliferated during the Early Cretaceous (145–100 Mya) while Australia was still linked to Antarctica to form East Gondwana


References


Notes


Sources

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External links

* *
Graphical subjects dealing with Tectonics and Paleontology



The Gondwana Map Project
* {{Authority control Historical continents Former supercontinents Biogeography Paleozoic paleogeography Mesozoic paleogeography Geology of Africa Geology of Antarctica Geology of Asia Geology of India Geology of Australia Geology of South America Prehistory of Antarctica Paleozoic Africa Paleozoic Antarctica Paleozoic Asia Paleozoic South America Mesozoic Africa Mesozoic Antarctica Mesozoic Asia Mesozoic South America