"Between about 450 million years ago and about 250 million years ago, the Northern Appalachian region was affected by a continental collision, in which the ancient African continent collided with the ancient North American continent to form the supercontinent Pangaea. Beginning about 200 million years ago, the present-day Atlantic Ocean began to form as plate tectonic forces began to rift apart the continent of Pangaea. The last major episode of geological activity to affect the bedrock in the NYC area occurred about 100 million years ago, during the Mesozoic era, when continental rifting that led to the opening of the"
"Atlantica Atlantica (; ""Atlantika"") is an ancient continent that formed during the Proterozoic about (two billion years ago, Ga) from various 2 Ga cratons located in what is now West Africa and eastern South America. The name, introduced by , was chosen because the continent opened up to form the South Atlantic Ocean. Atlantica formed simultaneously with Nena at about 1.9 Ga from Archaean cratons, including Amazonia in present-day South America, and the Congo, West Africa and North Africa Cratons in Africa. Atlantica separated from Nena between 1.6–1.4 Ga when Columbia — a supercontinent composed of Ur, Nena, and Atlantica"
"the Earth's continents were all joined as single landmass known as Pangea which existed beyond 200 million years ago. Pangea split from east to west into Laurasia, comprising North America and Eurasia, and Gondwana, the two remaining connected at Gibraltar with the Tethys Sea separating them. The presence of closely related organisms in both the Northern and Southern Hemispheres cannot be accounted for by migration. The Tarkine, located in island's far north west, is the largest temperate rainforest area in Australia covering approximately . The temperate rainforest has a high diversity of non-vascular plants: mosses, liverworts and lichens representing Australia's"
"Europe and Asia together as a single continent, dubbed ""Eurasia"". In this model, the world is divided into six continents, with North America and South America considered separate continents. Geologists use the term ""continent"" in a different manner from geographers. In geology a continent is defined by continental crust: a platform of metamorphic and igneous rock, largely of granitic composition. Some geologists restrict the term 'continent' to portions of the crust built around stable Precambrian ""shield"", typically 1.5 to 3.8 billion years old, called a craton. The craton itself is an accretionary complex of ancient mobile belts (mountain belts) from"
"Paleozoic the majority of all continental landmasses were united in the paleocontinent of Gondwana, containing the crust of future Africa, South America, southern Eurasia, Australia and Antarctica, which lay centered on the South Pole. Between 650 and 550 million years ago (in the Ediacaran period) the smaller continents of Laurentia (containing the future northeast section of North America), Baltica and Siberia had separated from Gondwana to move northward towards the equator. In the process, the Iapetus Ocean between Gondwana, Baltica and Laurentia closed. In the Early Ordovician period (about 480 million years ago) the microcontinent (a small fragment of continental"
"Siberia (continent) Siberia, also known as Angaraland (or simply Angara) and Angarida, is an ancient craton located in the heart of Siberia. Today forming the Central Siberian Plateau, it formed an independent continent before the Permian period. Angaraland was named in the 1880s by Austrian geologist Eduard Suess who erroneously believed that in the Paleozoic there were two large continents in the Northern Hemisphere: ""Atlantis"", North America connected to Europe by a peninsula (=Greenland and Iceland); and ""Angara-land"", eastern Asia, named after the Angara River in Siberia. About 2.5 billion years ago (Siderian), Siberia was part of a continent of"
"Ur (continent) Ur is a proposed supercontinent that formed in the Archean (3.1 billion). In Roger's reconstruction Ur is half a billion years older than Arctica and, in the early period of its existence, it was probably the only continent on Earth, and as such can be considered a supercontinent, though it was probably smaller than present-day Australia. In more recent works geologists often refer to both Ur and other proposed Archaean continental assemblages as supercratons. Ur can, nevertheless, be half a billion years younger than Vaalbara, but the concepts of these two early cratonic assemblages are incompatible. About 1,300–1,071"
"Gondwana Gondwana (),(or Gondwanaland), was a supercontinent that existed from the Neoproterozoic (about 550 million years ago) until the Carboniferous (about 320 million years ago). It was formed by the accretion of several cratons. Eventually, Gondwana became the largest piece of continental crust of the Paleozoic Era, covering an area of about . During the Carboniferous, it merged with Euramerica to form a larger supercontinent called Pangaea. Gondwana (and Pangaea) gradually broke up during the Mesozoic Era. The remnants of Gondwana make up about two-thirds of today's continental area, including South America, Africa, Antarctica, Australia, and the Indian Subcontinent. The"
"Rheic Ocean after Rhea, sister of Iapetus. At the beginning of the Paleozoic Era, about 540 million years ago, most of the continental mass on Earth was clustered around the south pole as the paleocontinent Gondwana. The exception was formed by a number of smaller continents, such as Laurentia and Baltica. The Paleozoic ocean between Gondwana, Laurentia and Baltica is called the Iapetus Ocean. The northern edge of Gondwana had been dominated by the Cadomian orogeny during the Ediacaran period. This orogeny formed a cordillera-type volcanic arc where oceanic crust subducted below Gondwana. When a mid-oceanic ridge subducted under an"
"Arctica Arctica or Arctida was an ancient continent which formed approximately 2.565 billion years ago in the Neoarchean era. It was made of Archaean cratons, including the Aldan and Anabar/Angara cratons in Siberia and the Slave, Wyoming, Superior, and North Atlantic cratons in North America. Arctica was named by because the Arctic Ocean formed by the separation of the North American and Siberian cratons. Russian geologists writing in English call the continent ""Arctida"" since it was given that name in 1987, alternatively the Hyperborean craton, in reference to the hyperboreans in Greek mythology. Nikolay Shatsky () was the first to"
"Archean The Archean Eon (, also spelled Archaean or Archæan) is one of the four geologic eons of Earth history, occurring (4 to 2.5 billion years ago). During the Archean, the Earth's crust had cooled enough to allow the formation of continents and life started to form. Archean (or Archaean) comes from the ancient Greek (""""), meaning ""beginning, origin"". Its earliest use is from 1872, when it meant ""of the earliest geological age."" Before the Hadean Eon was recognized, the Archean spanned Earth's early history from its formation about 4,540 million years ago until 2,500 million years ago. Instead of"
"the Bundelkhand-Aravalli block and the other Archaean blocks. 2.8–2.6 Gya metamorphism in Dharwar and Bundelkhand indicate that the stabilisation of Ur probably continued until the end of that period. Ur (continent) Ur is a proposed supercontinent that formed in the Archean (3.1 billion). In Roger's reconstruction Ur is half a billion years older than Arctica and, in the early period of its existence, it was probably the only continent on Earth, and as such can be considered a supercontinent, though it was probably smaller than present-day Australia. In more recent works geologists often refer to both Ur and other proposed"
"Earth, land""). The concept that the continents once formed a continuous land mass was first proposed by Alfred Wegener, the originator of the scientific theory of continental drift, in his 1912 publication ""The Origin of Continents"" (""Die Entstehung der Kontinente""). 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 that he called the """"Urkontinent"""". The name ""Pangea"" occurs in the 1920 edition of ""Die Entstehung der"
"fragments in northern Greenland and Northern Canada and in the submerged Lomonosov Ridge. Arctica Arctica or Arctida was an ancient continent which formed approximately 2.565 billion years ago in the Neoarchean era. It was made of Archaean cratons, including the Aldan and Anabar/Angara cratons in Siberia and the Slave, Wyoming, Superior, and North Atlantic cratons in North America. Arctica was named by because the Arctic Ocean formed by the separation of the North American and Siberian cratons. Russian geologists writing in English call the continent ""Arctida"" since it was given that name in 1987, alternatively the Hyperborean craton, in reference"
"single supercontinent called Columbia with substantial continental shelves. An asteroid (estimated at 10 km across) slammed into waters about 1,000 m deep some 1.85 billion years ago. Computer models suggest that the tsunami would have been at least 1,000 metres high at the centre, and 100 metres high about 3,000 kilometres away. Those immense waves and large underwater landslides triggered by the impact stirred the ocean, bringing oxygenated waters from the surface down to the ocean floor. Sediments deposited on the seafloor before the impact, including banded iron formations, contained little if any oxidized iron (Fe(III)), but were high in"
"Terra Australis Terra Australis (Latin for ""South Land"") was a hypothetical continent first posited in antiquity and which appeared on maps between the 15th and 18th centuries. The existence of Terra Australis was not based on any survey or direct observation, but rather on the idea that continental land in the Northern Hemisphere should be balanced by land in the south. This theory of balancing land has been documented as early as the 5th century on maps by Macrobius, who uses the term Australis on his maps. Other names for the hypothetical continent have included Terra Australis Ignota, Terra Australis"
"continents have been accurately determined back to the early Jurassic, shortly before the breakup of Pangaea (see animated image). The earlier continent Gondwana is not considered a supercontinent under the first definition, since the landmasses of Baltica, Laurentia and Siberia were separate at the time. The following table displays historical supercontinents, using a general definition. There are two contrasting models for supercontinent evolution through geological time. The first model theorizes that at least two separate supercontinents existed comprising Vaalbara (from ~3636 to ) and Kenorland (from ~2720 to ). The Neoarchean supercontinent consisted of Superia and Sclavia. These parts of"
"demarcated by GSSPs. The Precambrian could be divided into five ""natural"" eons, characterized as follows: The movement of Earth's plates has caused the formation and break-up of continents over time, including occasional formation of a supercontinent containing most or all of the landmass. The earliest known supercontinent was Vaalbara. It formed from proto-continents and was a supercontinent 3.636 billion years ago. Vaalbara broke up c. 2.845–2.803 Ga ago. The supercontinent Kenorland was formed c. 2.72 Ga ago and then broke sometime after 2.45–2.1 Ga into the proto-continent cratons called Laurentia, Baltica, Yilgarn craton, and Kalahari. The supercontinent Columbia or Nuna"
"Zealandia Zealandia (), also known as the New Zealand continent or Tasmantis is an almost entirely submerged mass of continental crust that sank after breaking away from Australia 60–85 million years ago, having separated from Antarctica between 85 and 130 million years ago. It has variously been described as a continental fragment, a microcontinent, a submerged continent, and a continent. The name and concept for Zealandia was proposed by Bruce Luyendyk in 1995. Zealandia's status as a continent is not universally accepted, but New Zealand geologist Nick Mortimer has commented that ""if it wasn't for the ocean"" it would have"
"temperatures planet-wide plummeted to below freezing. Despite the anoxia indicated by the BIF, photosynthesis continued, stabilizing climates at new levels during the second part of the Proterozoic Era. Kenorland Kenorland was one of the earliest known supercontinents on Earth. It is thought to have formed during the Neoarchaean Era c. 2.72 billion years ago (2.72 Ga) by the accretion of Neoarchaean cratons and the formation of new continental crust. It comprised what later became Laurentia (the core of today's North America and Greenland), Baltica (today's Scandinavia and Baltic), Western Australia and Kalaharia. It also formed a substantial and substantive part"
"Plateau (off Norway), Faroe-Shetland Basin, Hebrides, Outer Moray Firth and Denmark. The supercontinent known as Pangea existed during the late Paleozoic and early Mesozoic eras and began to rift around 200 million years ago. Pangea had three major phases of breakup. The first major phase began in the Early-Middle Jurassic, taking place between North America and Africa. The second major phase of breakup began in the Early Cretaceous. The South Atlantic Ocean opened around 140 million years ago as Africa separated from South America, and about the same time, India separated from Antarctica and Australia, forming the central Indian Ocean."
"believed to be real) were: Terra Australis Terra Australis (Latin for ""South Land"") was a hypothetical continent first posited in antiquity and which appeared on maps between the 15th and 18th centuries. The existence of Terra Australis was not based on any survey or direct observation, but rather on the idea that continental land in the Northern Hemisphere should be balanced by land in the south. This theory of balancing land has been documented as early as the 5th century on maps by Macrobius, who uses the term Australis on his maps. Other names for the hypothetical continent have included"
"Pannotia Pannotia (from Greek: ""pan-"", ""all"", ""-nótos"", ""south""; meaning ""all southern land""), also known as Vendian supercontinent, Greater Gondwana, and the Pan-African supercontinent, was a relatively short-lived Neoproterozoic supercontinent that formed at the end of the Precambrian during the Pan-African orogeny (650–500 Ma) and broke apart 560 Ma with the opening of the Iapetus Ocean. Pannotia formed when Laurentia was located adjacent to the two major South American cratons, Amazonia and Río de la Plata. The opening of the Iapetus Ocean separated Laurentia from Baltica, Amazonia, and Río de la Plata. was probably the first to propose a Proterozoic supercontinent"
"proposes a series of supercontinents: Vaalbara ( 3.6 to c. 2.8 billion years ago); Ur ( 3 billion years ago); Kenorland ( 2.7 to 2.1 billion years ago); Columbia ( 1.8 to 1.5 billion years ago); Rodinia ( 1.25 billion to 750 million years ago); and Pannotia ( 600 million years ago), whose dispersal produced the fragments that ultimately collided to form Pangaea. The second view (Protopangea-Paleopangea), based on both palaeomagnetic and geological evidence, is that supercontinent cycles did not occur before about 0.6 Ga (during the Ediacaran Period). Instead, the continental crust comprised a single supercontinent from about 2.7"
"Supercontinent cycle The supercontinent cycle is the quasi-periodic aggregation and dispersal of Earth's continental crust. There are varying opinions as to whether the amount of continental crust is increasing, decreasing, or staying about the same, but it is agreed that the Earth's crust is constantly being reconfigured. One complete supercontinent cycle is said to take 300 to 500 million years. Continental collision makes fewer and larger continents while rifting makes more and smaller continents. The most recent supercontinent, Pangaea, formed about 300 million years ago (0.3 Ga). There are two different views on the history of earlier supercontinents. The first"
"Baltica became an isolated continent — a 200 million year period when Baltica was truly a separate continent. Laurentia and Baltica formed a single continent until 1.265 Ga which broke up some time before 0.99 Ga. After the subsequent closure of the Mirovoi Ocean Laurentia, Baltica and Amazonia remained merged until the opening of the Iapetus Ocean in the Neoproterozoic. The Western Gneiss Region in northern Norway is composed of 1650-950 Ma-old gneisses overlain by continental and oceanic allochtons that were transferred from Laurentia to Baltica during the Scandian orogeny. The allochtons were accreted to Baltica during the closure of"
"Columbia (supercontinent) Columbia, also known as Nuna and Hudsonland, was one of Earth's ancient supercontinents. It was first proposed by and is thought to have existed approximately in the Paleoproterozoic Era. proposed that the assembly of the supercontinent Columbia was completed by global-scale collisional events during 2.1–1.8 Ga. Columbia consisted of proto-cratons that made up the cores of the continents of Laurentia, Baltica, Ukrainian Shield, Amazonian Shield, Australia, and possibly Siberia, North China, and Kalaharia as well. The evidence of Columbia's existence is based upon geological and paleomagnetic data. Columbia is estimated to have been approximately from North to South"
"formed 2.06–1.82 billion years ago and broke up about 1.5–1.35 billion years ago. The supercontinent Rodinia is thought to have formed about 1.13–1.071 billion years ago, to have embodied most or all of Earth's continents and to have broken up into eight continents around 750–600 million years ago. Precambrian The Precambrian (or Pre-Cambrian, sometimes abbreviated pЄ, or Cryptozoic) is the earliest part of Earth's history, set before the current Phanerozoic Eon. The Precambrian is so named because it preceded the Cambrian, the first period of the Phanerozoic eon, which is named after Cambria, the Latinised name for Wales, where rocks"
"ago. The islands still retain plants that originated in Gondwana and spread to the Southern Hemisphere continents later. However, strong evidence exists of glaciation during the Carboniferous to Permian time, especially in South Africa. Gondwana Gondwana (),(or Gondwanaland), was a supercontinent that existed from the Neoproterozoic (about 550 million years ago) until the Carboniferous (about 320 million years ago). It was formed by the accretion of several cratons. Eventually, Gondwana became the largest piece of continental crust of the Paleozoic Era, covering an area of about . During the Carboniferous, it merged with Euramerica to form a larger supercontinent called"
"to the north and Gondwana to the south. From the Silurian (440 ) through the Jurassic periods, the Paleo-Tethys Ocean existed between the Hunic terranes and Gondwana. Over a period of 400 million years, continental terranes intermittently separated from Gondwana in the Southern Hemisphere to migrate northward to form Asia in the Northern Hemisphere. About 250 Mya, during the Triassic, a new ocean began forming in the southern end of the Paleo-Tethys Ocean. A rift formed along the northern continental shelf of Southern Pangaea (Gondwana). Over the next 60 million years, that piece of shelf, known as Cimmeria, traveled north,"
"Euramerica Euramerica (also known as Laurussia – not to be confused with Laurasia, – the Old Red Continent or the Old Red Sandstone Continent) was a minor supercontinent created in the Devonian as the result of a collision between the Laurentian, Baltica, and Avalonia cratons during the Caledonian orogeny, about 410 million years ago. In the Late Carboniferous, tropical rainforests lay over the equator of Euramerica. A major, abrupt change in vegetation occurred when the climate aridified. The forest fragmented and the lycopsids which dominated these wetlands thinned out, being replaced by opportunistic ferns. There was also a great loss"
"Nena (supercontinent) Nena, an acronym for Northern Europe–North America, is the Early Proterozoic amalgamation of Baltica and Laurentia into a single ""cratonic landmass"", a name first proposed in 1990. Since then several similar Proterozoic supercontinents have been proposed, including Nuna and Arctica, that include other Archaean cratons, such as Siberia and East Antarctica. In the original concept Nena formed in the Penkean, Makkovikan, Ketilidian, and Svecofennian orogenies. However, because Nena excludes several known Archaean cratons, including those in India and Australia, it is strictly speaking not a supercontinent. Nena, or Nuna, can, nevertheless be though of as the core of"
"Kenorland Kenorland was one of the earliest known supercontinents on Earth. It is thought to have formed during the Neoarchaean Era c. 2.72 billion years ago (2.72 Ga) by the accretion of Neoarchaean cratons and the formation of new continental crust. It comprised what later became Laurentia (the core of today's North America and Greenland), Baltica (today's Scandinavia and Baltic), Western Australia and Kalaharia. It also formed a substantial and substantive part of Nena, the supercontinent associated with the Sudbury Basin Impact. Swarms of volcanic dikes and their paleomagnetic orientation as well as the existence of similar stratigraphic sequences permit"