Pangaea Ultima
Encyclopedia
Pangaea Ultima is a possible future supercontinent
configuration and an alternative to the Amasia
supercontinent. Consistent with the supercontinent cycle
, Pangaea Ultima could occur within the next 250 million years. This potential configuration, hypothesized by Christopher Scotese
, earned its name from its similarity to the previous Pangaea
supercontinent. The concept was based on examination of past cycles of formation and breakup of supercontinents, not on current understanding of the mechanisms of tectonic change, which are too imprecise to project that far in the future. "It's all pretty much fantasy to start with", Scotese has said. "But it's a fun exercise to think about what might happen. And you can only do it if you have a really clear idea of why things happen in the first place."
Supercontinents describe the merger of all, or nearly all, of the Earth
's landmass into a single contiguous continent
. In the Pangaea Ultima scenario, subduction
at the western Atlantic, east of the Americas
, leads to the subduction of the Atlantic mid-ocean ridge
followed by subduction destroying the Atlantic oceanic basin
, causing the Atlantic Ocean
to close, bringing the Americas
back together with Africa
and Europe
. As with most supercontinents, the interior of Pangaea Proxima would probably become a semi-arid desert
prone to temperature extremes.
.
Around 50 million years from now, North America
is predicted to have shifted slightly west and Eurasia
would shift to the east, and possibly even to the south, bringing Great Britain
closer to the North Pole and Siberia
southward towards warm, subtropical latitudes. Africa is predicted to collide with Europe and Arabia, closing the Mediterranean Sea
(completely closing the Tethys Ocean
(or Neotethys) and the Red Sea
). A long mountain range would then extend from Iberia
, across Southern Europe
(the Mediterranean Mountain Range), through the Mideast and into Asia
. Some are even predicted to have peaks higher than Mt. Everest. Similarly, Australia
is predicted to beach itself on the doorstep of Southeast Asia and a new subduction zone is predicted to encircle Australia and extend westward across the Central Indian Ocean. Meanwhile, Southern California
and Baja California
are predicted to have already collided with Alaska with new mountain ranges formed between them.
About 150 million years from now, the Atlantic ocean is predicted to stop widening and begin to shrink because a bit of the Atlantic Ocean mid-ridge will have been subducted. In this scenario, a mid-ocean ridge between South America
and Africa
will probably be subducted first, the Atlantic Ocean
is predicted to have narrowed as a result of subduction beneath the Americas. The Indian Ocean
is also predicted to be smaller due to northward subduction of oceanic crust into the Central Indian trench. North
and South America
may be pushed back southeast, and southern Africa would almost hit equator and have reached the Northern hemisphere. Australia may join back to Antarctica, meeting the South Pole.
When the last bit of the Mid-Atlantic spreading ridge is subducted beneath the Americas, the Atlantic Ocean is predicted to rapidly close with a new Pangaea forming.
At 250 million years in the future, the Atlantic and Indian oceans are predicted to have closed. North America
is predicted to have already collided with Africa
, but be in a more southerly position than where it rifted. South America
is predicted to be wrapped around the southern tip of Africa, with Patagonia
in contact with Indonesia
, enclosing a remnant of the Indian Ocean (called the Indo-Atlantic Ocean). Antarctica would then once again be at the South Pole and the Pacific will have grown wider, encircling half the Earth
.
, Novopangea, and Pangaea Ultima are discussed in the book Supercontinent by Ted Nield, and illustrated in "Pangaea, the comeback" in the New Scientist magazine issued 20 October 2007.
Supercontinent
In geology, a supercontinent is a landmass comprising more than one continental core, or craton. The assembly of cratons and accreted terranes that form Eurasia qualifies as a supercontinent today.-History:...
configuration and an alternative to the Amasia
Amasia (continent)
Amasia is a possible future supercontinent that could be formed by the merger of Asia and North America and is an alternative to Pangaea Ultima. This relies mostly on the fact that the Pacific Plate is already subducting under Eurasia and North America, a process which if continued will eventually...
supercontinent. Consistent with the supercontinent cycle
Supercontinent cycle
The supercontinent cycle describes 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...
, Pangaea Ultima could occur within the next 250 million years. This potential configuration, hypothesized by Christopher Scotese
Christopher Scotese
Christopher R. Scotese is geologist at the University of Texas at Arlington. He received his PhD from the University of Chicago in 1985. He is creator of the Paleomap Project, which aims to map Earth over the last billion years, and is credited with predicting Pangaea Ultima, a possible future...
, earned its name from its similarity to the previous Pangaea
Pangaea
Pangaea, Pangæa, or Pangea is hypothesized as a supercontinent that existed during the Paleozoic and Mesozoic eras about 250 million years ago, before the component continents were separated into their current configuration....
supercontinent. The concept was based on examination of past cycles of formation and breakup of supercontinents, not on current understanding of the mechanisms of tectonic change, which are too imprecise to project that far in the future. "It's all pretty much fantasy to start with", Scotese has said. "But it's a fun exercise to think about what might happen. And you can only do it if you have a really clear idea of why things happen in the first place."
Supercontinents describe the merger of all, or nearly all, of the Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
's landmass into a single contiguous continent
Continent
A continent is one of several very large landmasses on Earth. They are generally identified by convention rather than any strict criteria, with seven regions commonly regarded as continents—they are : Asia, Africa, North America, South America, Antarctica, Europe, and Australia.Plate tectonics is...
. In the Pangaea Ultima scenario, subduction
Subduction
In geology, subduction is the process that takes place at convergent boundaries by which one tectonic plate moves under another tectonic plate, sinking into the Earth's mantle, as the plates converge. These 3D regions of mantle downwellings are known as "Subduction Zones"...
at the western Atlantic, east of the Americas
Americas
The Americas, or America , are lands in the Western hemisphere, also known as the New World. In English, the plural form the Americas is often used to refer to the landmasses of North America and South America with their associated islands and regions, while the singular form America is primarily...
, leads to the subduction of the Atlantic mid-ocean ridge
Mid-ocean ridge
A mid-ocean ridge is a general term for an underwater mountain system that consists of various mountain ranges , typically having a valley known as a rift running along its spine, formed by plate tectonics. This type of oceanic ridge is characteristic of what is known as an oceanic spreading...
followed by subduction destroying the Atlantic oceanic basin
Oceanic basin
Hydrologically, an oceanic basin may be anywhere on Earth that is covered by seawater, but geologically ocean basins are large geologic basins that are below sea level...
, causing the Atlantic Ocean
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
to close, bringing the Americas
Americas
The Americas, or America , are lands in the Western hemisphere, also known as the New World. In English, the plural form the Americas is often used to refer to the landmasses of North America and South America with their associated islands and regions, while the singular form America is primarily...
back together with Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
and Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
. As with most supercontinents, the interior of Pangaea Proxima would probably become a semi-arid desert
Desert
A desert is a landscape or region that receives an extremely low amount of precipitation, less than enough to support growth of most plants. Most deserts have an average annual precipitation of less than...
prone to temperature extremes.
Formation
According to the Pangaea Ultima hypothesis, the Atlantic and Indian Oceans will continue to get wider until new subduction zones bring the continents back together, forming a future Pangaea. Most continents and microcontinents are predicted to collide with Eurasia, just as they did when most continents collided to LaurentiaLaurentia
Laurentia is a large area of continental craton, which forms the ancient geological core of the North American continent...
.
Around 50 million years from now, North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
is predicted to have shifted slightly west and Eurasia
Eurasia
Eurasia is a continent or supercontinent comprising the traditional continents of Europe and Asia ; covering about 52,990,000 km2 or about 10.6% of the Earth's surface located primarily in the eastern and northern hemispheres...
would shift to the east, and possibly even to the south, bringing Great Britain
Great Britain
Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...
closer to the North Pole and Siberia
Siberia
Siberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...
southward towards warm, subtropical latitudes. Africa is predicted to collide with Europe and Arabia, closing the Mediterranean Sea
Mediterranean Sea
The Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...
(completely closing the Tethys Ocean
Tethys Ocean
The Tethys Ocean was an ocean that existed between the continents of Gondwana and Laurasia during the Mesozoic era before the opening of the Indian Ocean.-Modern theory:...
(or Neotethys) and the Red Sea
Red Sea
The Red Sea is a seawater inlet of the Indian Ocean, lying between Africa and Asia. The connection to the ocean is in the south through the Bab el Mandeb strait and the Gulf of Aden. In the north, there is the Sinai Peninsula, the Gulf of Aqaba, and the Gulf of Suez...
). A long mountain range would then extend from Iberia
Iberia
The name Iberia refers to three historical regions of the old world:* Iberian Peninsula, in Southwest Europe, location of modern-day Portugal and Spain** Prehistoric Iberia...
, across Southern Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
(the Mediterranean Mountain Range), through the Mideast and into Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
. Some are even predicted to have peaks higher than Mt. Everest. Similarly, Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
is predicted to beach itself on the doorstep of Southeast Asia and a new subduction zone is predicted to encircle Australia and extend westward across the Central Indian Ocean. Meanwhile, Southern California
Southern California
Southern California is a megaregion, or megapolitan area, in the southern area of the U.S. state of California. Large urban areas include Greater Los Angeles and Greater San Diego. The urban area stretches along the coast from Ventura through the Southland and Inland Empire to San Diego...
and Baja California
Baja California
Baja California officially Estado Libre y Soberano de Baja California is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is both the northernmost and westernmost state of Mexico. Before becoming a state in 1953, the area was known as the North...
are predicted to have already collided with Alaska with new mountain ranges formed between them.
About 150 million years from now, the Atlantic ocean is predicted to stop widening and begin to shrink because a bit of the Atlantic Ocean mid-ridge will have been subducted. In this scenario, a mid-ocean ridge between South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
and Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
will probably be subducted first, the Atlantic Ocean
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
is predicted to have narrowed as a result of subduction beneath the Americas. The Indian Ocean
Indian Ocean
The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...
is also predicted to be smaller due to northward subduction of oceanic crust into the Central Indian trench. North
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
and South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
may be pushed back southeast, and southern Africa would almost hit equator and have reached the Northern hemisphere. Australia may join back to Antarctica, meeting the South Pole.
When the last bit of the Mid-Atlantic spreading ridge is subducted beneath the Americas, the Atlantic Ocean is predicted to rapidly close with a new Pangaea forming.
At 250 million years in the future, the Atlantic and Indian oceans are predicted to have closed. North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
is predicted to have already collided with Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
, but be in a more southerly position than where it rifted. South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
is predicted to be wrapped around the southern tip of Africa, with Patagonia
Patagonia
Patagonia is a region located in Argentina and Chile, integrating the southernmost section of the Andes mountains to the southwest towards the Pacific ocean and from the east of the cordillera to the valleys it follows south through Colorado River towards Carmen de Patagones in the Atlantic Ocean...
in contact with Indonesia
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...
, enclosing a remnant of the Indian Ocean (called the Indo-Atlantic Ocean). Antarctica would then once again be at the South Pole and the Pacific will have grown wider, encircling half the Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
.
Other theories
AmasiaAmasia (continent)
Amasia is a possible future supercontinent that could be formed by the merger of Asia and North America and is an alternative to Pangaea Ultima. This relies mostly on the fact that the Pacific Plate is already subducting under Eurasia and North America, a process which if continued will eventually...
, Novopangea, and Pangaea Ultima are discussed in the book Supercontinent by Ted Nield, and illustrated in "Pangaea, the comeback" in the New Scientist magazine issued 20 October 2007.