Flood basalt

Flood basalt

Overview
A flood basalt or trap basalt is the result of a giant volcanic eruption or series of eruptions that coats large stretches of land or the ocean
Ocean
An ocean is a major body of saline water, and a principal component of the hydrosphere. Approximately 71% of the Earth's surface is covered by ocean, a continuous body of water that is customarily divided into several principal oceans and smaller seas.More than half of this area is over 3,000...

 floor with basalt
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...

 lava
Lava
Lava refers both to molten rock expelled by a volcano during an eruption and the resulting rock after solidification and cooling. This molten rock is formed in the interior of some planets, including Earth, and some of their satellites. When first erupted from a volcanic vent, lava is a liquid at...

. Flood basalts have occurred on 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...

al scales (large igneous province
Large igneous province
A Large Igneous Province is an extremely large accumulation of igneous rocks—intrusive, extrusive, or both—in the earth's crust...

s) in prehistory
Prehistory
Prehistory is the span of time before recorded history. Prehistory can refer to the period of human existence before the availability of those written records with which recorded history begins. More broadly, it refers to all the time preceding human existence and the invention of writing...

, creating great plateau
Plateau
In geology and earth science, a plateau , also called a high plain or tableland, is an area of highland, usually consisting of relatively flat terrain. A highly eroded plateau is called a dissected plateau...

s and mountain range
Mountain range
A mountain range is a single, large mass consisting of a succession of mountains or narrowly spaced mountain ridges, with or without peaks, closely related in position, direction, formation, and age; a component part of a mountain system or of a mountain chain...

s. Flood basalts have erupted at random intervals throughout geological history and are clear evidence that 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...

 undergoes periods of enhanced activity rather than being in a uniform steady state.

One proposed explanation for flood basalts is that they are caused by the combination of continental rifting and its associated decompression melting, in conjunction with a mantle plume
Mantle plume
A mantle plume is a hypothetical thermal diapir of abnormally hot rock that nucleates at the core-mantle boundary and rises through the Earth's mantle. Such plumes were invoked in 1971 to explain volcanic regions that were not thought to be explicable by the then-new theory of plate tectonics. Some...

 also undergoing decompression melting, producing vast quantities of a tholeiitic basaltic magma
Magma
Magma is a mixture of molten rock, volatiles and solids that is found beneath the surface of the Earth, and is expected to exist on other terrestrial planets. Besides molten rock, magma may also contain suspended crystals and dissolved gas and sometimes also gas bubbles. Magma often collects in...

.
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Unanswered Questions
Encyclopedia
A flood basalt or trap basalt is the result of a giant volcanic eruption or series of eruptions that coats large stretches of land or the ocean
Ocean
An ocean is a major body of saline water, and a principal component of the hydrosphere. Approximately 71% of the Earth's surface is covered by ocean, a continuous body of water that is customarily divided into several principal oceans and smaller seas.More than half of this area is over 3,000...

 floor with basalt
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...

 lava
Lava
Lava refers both to molten rock expelled by a volcano during an eruption and the resulting rock after solidification and cooling. This molten rock is formed in the interior of some planets, including Earth, and some of their satellites. When first erupted from a volcanic vent, lava is a liquid at...

. Flood basalts have occurred on 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...

al scales (large igneous province
Large igneous province
A Large Igneous Province is an extremely large accumulation of igneous rocks—intrusive, extrusive, or both—in the earth's crust...

s) in prehistory
Prehistory
Prehistory is the span of time before recorded history. Prehistory can refer to the period of human existence before the availability of those written records with which recorded history begins. More broadly, it refers to all the time preceding human existence and the invention of writing...

, creating great plateau
Plateau
In geology and earth science, a plateau , also called a high plain or tableland, is an area of highland, usually consisting of relatively flat terrain. A highly eroded plateau is called a dissected plateau...

s and mountain range
Mountain range
A mountain range is a single, large mass consisting of a succession of mountains or narrowly spaced mountain ridges, with or without peaks, closely related in position, direction, formation, and age; a component part of a mountain system or of a mountain chain...

s. Flood basalts have erupted at random intervals throughout geological history and are clear evidence that 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...

 undergoes periods of enhanced activity rather than being in a uniform steady state.

One proposed explanation for flood basalts is that they are caused by the combination of continental rifting and its associated decompression melting, in conjunction with a mantle plume
Mantle plume
A mantle plume is a hypothetical thermal diapir of abnormally hot rock that nucleates at the core-mantle boundary and rises through the Earth's mantle. Such plumes were invoked in 1971 to explain volcanic regions that were not thought to be explicable by the then-new theory of plate tectonics. Some...

 also undergoing decompression melting, producing vast quantities of a tholeiitic basaltic magma
Magma
Magma is a mixture of molten rock, volatiles and solids that is found beneath the surface of the Earth, and is expected to exist on other terrestrial planets. Besides molten rock, magma may also contain suspended crystals and dissolved gas and sometimes also gas bubbles. Magma often collects in...

. These have a very low viscosity
Viscosity
Viscosity is a measure of the resistance of a fluid which is being deformed by either shear or tensile stress. In everyday terms , viscosity is "thickness" or "internal friction". Thus, water is "thin", having a lower viscosity, while honey is "thick", having a higher viscosity...

, which is why they 'flood' rather than form taller volcano
Volcano
2. Bedrock3. Conduit 4. Base5. Sill6. Dike7. Layers of ash emitted by the volcano8. Flank| 9. Layers of lava emitted by the volcano10. Throat11. Parasitic cone12. Lava flow13. Vent14. Crater15...

es. Another explanation is that they result from the release, over a short time period, of melt that has accumulated in the mantle over a long time period.

The Deccan Traps
Deccan Traps
The Deccan Traps are a large igneous province located on the Deccan Plateau of west-central India and one of the largest volcanic features on Earth. They consist of multiple layers of solidified flood basalt that together are more than thick and cover an area of and a volume of...

 of central India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

, the Siberian Traps
Siberian Traps
The Siberian Traps form a large region of volcanic rock, known as a large igneous province, in the Russian region of Siberia. The massive eruptive event which formed the traps, one of the largest known volcanic events of the last 500 million years of Earth's geological history, continued for...

, and the Columbia River Plateau
Columbia River Plateau
The Columbia Plateau is a geologic and geographic region that lies across parts of the U.S. states of Washington, Oregon, and Idaho. It is a wide flood basalt plateau between the Cascade Range and the Rocky Mountains, cut through by the Columbia River...

 of western 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...

 are three regions covered by prehistoric flood basalts. The two largest flood basalt events in historic time have been at Eldgjá
Eldgjá
Eldgjá is a volcanic canyon in Iceland. Eldgjá and the Katla volcano are part of the same volcanic system in the south of the country. Eldgjá means "fire canyon" in Icelandic....

 and Lakagigar, both in Iceland
Iceland
Iceland , described as the Republic of Iceland, is a Nordic and European island country in the North Atlantic Ocean, on the Mid-Atlantic Ridge. Iceland also refers to the main island of the country, which contains almost all the population and almost all the land area. The country has a population...

. The largest and best-preserved continental flood basalt terrain on Earth is part of the Mackenzie Large Igneous Province
Mackenzie Large Igneous Province
The Mackenzie Large Igneous Province is a major Mesoproterozoic large igneous province of the southwestern, western and northwestern Canadian Shield in Canada. It consists of a group of related igneous rocks that were formed during a massive igneous event starting about 1,270 million years ago...

 in Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

. The maria
Lunar mare
The lunar maria are large, dark, basaltic plains on Earth's Moon, formed by ancient volcanic eruptions. They were dubbed maria, Latin for "seas", by early astronomers who mistook them for actual seas. They are less reflective than the "highlands" as a result of their iron-rich compositions, and...

 on the Moon
Moon
The Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...

 are additional, even more extensive, flood basalts. Flood basalts on the ocean floor produce oceanic plateau
Oceanic plateau
An oceanic plateau is a large, relatively flat submarine region that rises well above the level of the ambient seabed. While many oceanic plateaus are composed of continental crust, and often form a step interrupting the continental slope, some plateaus are undersea remnants of large igneous...

s.

The surface covered by one eruption can vary from around 200,000 km² (Karoo
Karoo-Ferrar
Karoo and Ferrar denote a major geologic province consisting of flood basalt, which mostly covers South Africa and Antarctica, although portions extend further into southern Africa and into South America, India, Australia and New Zealand...

) to 1,500,000 km² (Siberian Traps). The thickness can vary from 2000 metres (Deccan Traps) to 12,000 m (Lake Superior
Lake Superior
Lake Superior is the largest of the five traditionally-demarcated Great Lakes of North America. It is bounded to the north by the Canadian province of Ontario and the U.S. state of Minnesota, and to the south by the U.S. states of Wisconsin and Michigan. It is the largest freshwater lake in the...

). These are smaller than the original volume
Volume
Volume is the quantity of three-dimensional space enclosed by some closed boundary, for example, the space that a substance or shape occupies or contains....

s due to erosion
Erosion
Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...

. .

Petrography



Flood basalts have tholeiite and olivine
Olivine
The mineral olivine is a magnesium iron silicate with the formula 2SiO4. It is a common mineral in the Earth's subsurface but weathers quickly on the surface....

 compositions (according to the classification of Yoder
Yoder
Yoder is a surname originating in the Canton of Berne in Switzerland. The surname is a shortened version of St. Theodorus, the first Roman Catholic bishop of Octodurum in present day Martigny, Switzerland. Theodorus—also known as St. Theodore of Grammont, St. Theodule, and St...

 and Tilley
Tilley (surname)
Tilley is a surname, and may refer to:*Arthur Augustus Tilley , academic of the University of Cambridge*Benjamin Franklin Tilley , officer in the United States Navy*Cecil Edgar Tilley*Christopher Tilley*Jack L...

). The composition of the basalts from the Paraná
Parana Basin
The Paraná Basin is a large sedimentary basin situated in the central-eastern part of South America. About 75% of its areal distribution occurs in Brazil, from Mato Grosso to Rio Grande do Sul states. The remainder area is distributed in eastern Paraguay, northeastern Argentina and northern...

 is fairly typical of that of flood basalts; it contains phenocryst
Phenocryst
thumb|right|300px|[[Granite]]s often have large [[feldspar|feldspatic]] phenocrysts. This granite, from the [[Switzerland|Swiss]] side of the [[Mont Blanc]] massif, has large white [[plagioclase]] phenocrysts, [[triclinic]] [[mineral]]s that give [[trapezium|trapezoid]] shapes when cut through)...

s occupying around 25% of the volume of rock, trapped in volcanic glass
Volcanic glass
Volcanic glass is the amorphous product of rapidly cooling magma. Like all types of glass, it is a state of matter intermediate between the close-packed, highly ordered array of a crystal and the highly disordered array of gas...

. These phenocrysts are pyroxenes (augite
Augite
Augite is a single chain inosilicate mineral, 2O6. The crystals are monoclinic and prismatic. Augite has two prominent cleavages, meeting at angles near 90 degrees.-Characteristics:Augite is a solid solution in the pyroxene group...

 and pigeonite
Pigeonite
Pigeonite is a mineral in the clinopyroxene group. It has a general formula of Si2O6. The calcium cation fraction can vary from 5% to 25%, with iron and magnesium making up the rest of the cations....

), plagioclase
Plagioclase
Plagioclase is an important series of tectosilicate minerals within the feldspar family. Rather than referring to a particular mineral with a specific chemical composition, plagioclase is a solid solution series, more properly known as the plagioclase feldspar series...

s, opaque crystal
Crystal
A crystal or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions. The scientific study of crystals and crystal formation is known as crystallography...

s such as titanomagnetite or ilmenite
Ilmenite
Ilmenite is a weakly magnetic titanium-iron oxide mineral which is iron-black or steel-gray. It is a crystalline iron titanium oxide . It crystallizes in the trigonal system, and it has the same crystal structure as corundum and hematite....

, and occasionally some olivine. Sometimes more differentiated volcanic products such as andesite
Andesite
Andesite is an extrusive igneous, volcanic rock, of intermediate composition, with aphanitic to porphyritic texture. In a general sense, it is the intermediate type between basalt and dacite. The mineral assemblage is typically dominated by plagioclase plus pyroxene and/or hornblende. Magnetite,...

s, dacite
Dacite
Dacite is an igneous, volcanic rock. It has an aphanitic to porphyritic texture and is intermediate in composition between andesite and rhyolite. The relative proportions of feldspars and quartz in dacite, and in many other volcanic rocks, are illustrated in the QAPF diagram...

s and rhyodacite
Rhyodacite
Rhyodacite is an extrusive volcanic rock intermediate in composition between dacite and rhyolite. It is the extrusive equivalent of granodiorite. Phenocrysts of sodium rich plagioclase, sanidine, quartz, and biotite or hornblende are typically set in an aphanitic to glassy light to intermediate...

s have been observed, but only in small quantities at the top of former magma chamber
Magma chamber
A magma chamber is a large underground pool of molten rock found beneath the surface of the Earth. The molten rock in such a chamber is under great pressure, and given enough time, that pressure can gradually fracture the rock around it creating outlets for the magma...

s.

Structures


Subaerial flood basalts can be of two kinds :
  • with a smooth or twisted surface : very compact surface; vesicles
    Vesicular texture
    Vesicular texture is a volcanic rock texture characterised by a rock being pitted with many cavities at its surface and inside. The texture is often found in extrusive aphanitic, or glassy, igneous rock...

     (gas bubbles) are rare. Degassing was easy (magma maintained at a high temperature
    Temperature
    Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...

     and more fluid
    Fluid
    In physics, a fluid is a substance that continually deforms under an applied shear stress. Fluids are a subset of the phases of matter and include liquids, gases, plasmas and, to some extent, plastic solids....

     in a chamber of a size such that confining pressure
    Pressure
    Pressure is the force per unit area applied in a direction perpendicular to the surface of an object. Gauge pressure is the pressure relative to the local atmospheric or ambient pressure.- Definition :...

    s did not confine gases to the melt before expulsion). Such lava flows may form underground rivers; when degassing fractures and conduits are present, very large flows may reach the surface.
  • with a chaotic surface : the basalt flood is very rich in bubbles of gas, with an irregular, fragmental surface. Degassing was difficult (less fluid magma expelled from a rift with no chance of progressive expansion in a hot chamber; the degassing took place closer to the surface where the flow forms a crust which cracks under the pressure of the gases in the flow itself and during more rapid cooling).

In the Massif Central
Massif Central
The Massif Central is an elevated region in south-central France, consisting of mountains and plateaux....

 in Auvergne
Auvergne (région)
Auvergne is one of the 27 administrative regions of France. It comprises the 4 departments of Allier, Puy de Dome, Cantal and Haute Loire.The current administrative region of Auvergne is larger than the historical province of Auvergne, and includes provinces and areas that historically were not...

, there is a good example of chaotic lava flow, produced by eruptions from Puy de la Vache and Puy de Lassolas
Puy de Lassolas
The Puy de Lassolas is a volcano in the Chaîne des Puys in France, peaking at 1187 metres. It forms, with the Puy de la Vache, a group of volcanic craters. Together, they thus form two half craters...

.

At depth, flows can crystallise more slowly, producing columnar jointing.

Geochemistry



Geochemical analysis of the major oxide
Oxide
An oxide is a chemical compound that contains at least one oxygen atom in its chemical formula. Metal oxides typically contain an anion of oxygen in the oxidation state of −2....

s reveals a composition close to that of 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...

 basalts (MORB) but also close to that of ocean island basalt
Ocean island basalt
Ocean island basalts or OIBs are basaltic rocks found on many volcanic islands away from tectonic plate boundaries typically associated with hot spots. Islands hosting ocean island basalts lie always above oceanic crust and are not limited to volcanic islands but occur also on volcanoes of any size...

s (OIB). These are in fact tholeiite
Tholeiite
The tholeiitic magma series is one of two main magma series in igneous rocks, the other magma series being the calc–alkaline. A magma series is a series of compositions that describes the evolution of a mafic magma, which is high in magnesium and iron and produces basalt or gabbro, as it...

s with a silicon dioxide
Silicon dioxide
The chemical compound silicon dioxide, also known as silica , is an oxide of silicon with the chemical formula '. It has been known for its hardness since antiquity...

 percentage close to 50%.

Two kinds of basaltic floods basalts can be distinguished :
  • those poor in P2O5 and in TiO2, called LPT
    LPT
    LPT is the original, and still common, name of the parallel port interface on IBM PC-compatible computers. It was designed to operate a text printer that used IBM's 8-bit extended ASCII character set. The name derives from the fact that "line printer" was a common generic term at the time for any...

     (low phosphorus
    Phosphorus
    Phosphorus is the chemical element that has the symbol P and atomic number 15. A multivalent nonmetal of the nitrogen group, phosphorus as a mineral is almost always present in its maximally oxidized state, as inorganic phosphate rocks...

     and titanium
    Titanium
    Titanium is a chemical element with the symbol Ti and atomic number 22. It has a low density and is a strong, lustrous, corrosion-resistant transition metal with a silver color....

    )
  • those rich in P2O5 and in TiO2, called HPT (high phosphorus and titanium)


The isotopic ratios 87Sr/86Sr and 206Pb/204Pb are different from that observed in general, which shows that the basalt flood magma was contaminated as it passed through the continental crust
Continental crust
The continental crust is the layer of igneous, sedimentary, and metamorphic rocks which form the continents and the areas of shallow seabed close to their shores, known as continental shelves. This layer is sometimes called sial due to more felsic, or granitic, bulk composition, which lies in...

. It is this contamination that explains the difference between the two kinds of basalt mentioned above. The LPT type has an excess of elements from the crust
Crust (geology)
In geology, the crust is the outermost solid shell of a rocky planet or natural satellite, which is chemically distinct from the underlying mantle...

 such as potassium
Potassium
Potassium is the chemical element with the symbol K and atomic number 19. Elemental potassium is a soft silvery-white alkali metal that oxidizes rapidly in air and is very reactive with water, generating sufficient heat to ignite the hydrogen emitted in the reaction.Potassium and sodium are...

 and strontium
Strontium
Strontium is a chemical element with the symbol Sr and the atomic number 38. An alkaline earth metal, strontium is a soft silver-white or yellowish metallic element that is highly reactive chemically. The metal turns yellow when exposed to air. It occurs naturally in the minerals celestine and...

.

The content in incompatible element
Incompatible element
An incompatible element is a term used in petrology and geochemistry to describe an element that is unsuitable in size and/or charge to the cation sites of the minerals, and is defined by the partition coefficient between rock-forming minerals and melt being much smaller than 1..During the...

s of basaltic floods is lower than that of ocean island basalts, but higher than that of mid-ocean ridge basalts.

Other occurrences and implications

  • Flood basalt volcanism
    Volcanism
    Volcanism is the phenomenon connected with volcanoes and volcanic activity. It includes all phenomena resulting from and causing magma within the crust or mantle of a planet to rise through the crust and form volcanic rocks on the surface....

     has been implicated (along with the impact of large asteroid
    Asteroid
    Asteroids are a class of small Solar System bodies in orbit around the Sun. They have also been called planetoids, especially the larger ones...

    s and/or comet
    Comet
    A comet is an icy small Solar System body that, when close enough to the Sun, displays a visible coma and sometimes also a tail. These phenomena are both due to the effects of solar radiation and the solar wind upon the nucleus of the comet...

    s, as well as disease
    Disease
    A disease is an abnormal condition affecting the body of an organism. It is often construed to be a medical condition associated with specific symptoms and signs. It may be caused by external factors, such as infectious disease, or it may be caused by internal dysfunctions, such as autoimmune...

     and long-term climate change
    Climate change
    Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions or the distribution of events around that average...

    s) in major mass extinction events in the past.

  • Basalt floods on the planet Venus
    Venus
    Venus is the second planet from the Sun, orbiting it every 224.7 Earth days. The planet is named after Venus, the Roman goddess of love and beauty. After the Moon, it is the brightest natural object in the night sky, reaching an apparent magnitude of −4.6, bright enough to cast shadows...

     are larger than those on Earth (see: Volcanism on Venus
    Volcanism on Venus
    The surface of Venus is dominated by volcanism and has produced more volcanoes than any other planet in the solar system. It has a surface that is 90% basalt, and about 80% of the planet consists of a mosaic of volcanic lava plains, indicating that volcanism played a major role in shaping its surface...

    ). Their study may help understand the mechanisms responsible for these major geological events.

List of flood basalts



All major continental flood basalts (also known as traps) and oceanic plateaus, together forming a listing of large igneous province
Large igneous province
A Large Igneous Province is an extremely large accumulation of igneous rocks—intrusive, extrusive, or both—in the earth's crust...

s, which is provided below. The listing ranges from the smallest Columbia flood basalts to the largest, although not yet well characterized remnants of a possible trap in eastern Siberia:
  1. The Columbia
    Columbia River
    The Columbia River is the largest river in the Pacific Northwest region of North America. The river rises in the Rocky Mountains of British Columbia, Canada, flows northwest and then south into the U.S. state of Washington, then turns west to form most of the border between Washington and the state...

    -Snake River
    Snake River
    The Snake is a major river of the greater Pacific Northwest in the United States. At long, it is the largest tributary of the Columbia River, the largest North American river that empties into the Pacific Ocean...

     flood basalts (see Columbia River Basalt Group
    Columbia River Basalt Group
    The Columbia River Basalt Group is a large igneous province that lies across parts of the Western United States. It is found in the U.S. states of Washington, Oregon, Idaho, Nevada, and California...

    )
  2. The Ethiopian and Yemen traps
    Arabian-Nubian Shield
    The Arabian-Nubian Shield is an exposure of Precambrian crystalline rocks on the flanks of the Red Sea. The crystalline rocks are mostly Neoproterozoic in age. Geographically - and from north to south - the ANS includes the nations of Israel, Jordan. Egypt, Saudi Arabia, Sudan, Eritrea,...

     in the Ethiopian Highlands
    Ethiopian Highlands
    The Ethiopian Highlands are a rugged mass of mountains in Ethiopia, Eritrea , and northern Somalia in the Horn of Africa...

  3. The North Atlantic Volcanic Province
    Brito-Arctic province
    The Brito-Arctic province is a major flood basalt province of the North Atlantic Ocean. Basaltic volcanism flowed in two main pulses. The first which occurred ~61 million years ago was of 2 x 106 km³ in total volume, into the current western and southeastern Greenland and northwestern Britain...

  4. The Deccan Traps
    Deccan Traps
    The Deccan Traps are a large igneous province located on the Deccan Plateau of west-central India and one of the largest volcanic features on Earth. They consist of multiple layers of solidified flood basalt that together are more than thick and cover an area of and a volume of...

     (India) 65 million years ago (end of Cretaceous
    Cretaceous
    The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

     period)
  5. The Caribbean large igneous province
    Caribbean large igneous province
    The Caribbean large igneous province consists of a major flood basalt, which created this large igneous province. It is the source of the current large eastern Pacific oceanic plateau, of which the Caribbean-Colombian oceanic plateau is the tectonized remnant. The deeper levels of the plateau have...

  6. The Kerguelen Plateau
    Kerguelen Plateau
    The Kerguelen Plateau is an underwater volcanic large igneous province , also the microcontinent and submerged continent in the southern Indian Ocean. It lies about 3,000 km to the southwest of Australia and is nearly three times the size of Japan...

  7. The Ontong Java–Manihiki–Hikurangi Plateau
  8. The Paraná and Etendeka traps
    Paraná and Etendeka traps
    The Paraná-Etendeka traps comprise a large igneous province which includes both the main Paraná traps as well as the smaller severed portions of the flood basalts at the Etendeka traps in Namibia and Angola. The original basalt flows occurred 128 to 138 million years ago...

     (Brazil-Namibia)
  9. The Karoo and Ferrar provinces
    Karoo-Ferrar
    Karoo and Ferrar denote a major geologic province consisting of flood basalt, which mostly covers South Africa and Antarctica, although portions extend further into southern Africa and into South America, India, Australia and New Zealand...

     (South Africa-Antarctica)
  10. The Central Atlantic Magmatic Province
    Central Atlantic Magmatic Province
    The Central Atlantic magmatic province is a large connected magma flow formed during the breakup of Pangaea during the Mesozoic Era. The initial breakup of Pangaea in early Jurassic time provided a legacy of basaltic dikes, sills, and lavas over a vast area around the present central North...

  11. The Siberian Traps
    Siberian Traps
    The Siberian Traps form a large region of volcanic rock, known as a large igneous province, in the Russian region of Siberia. The massive eruptive event which formed the traps, one of the largest known volcanic events of the last 500 million years of Earth's geological history, continued for...

     (Russia) 251 million years ago (end of Permian
    Permian
    The PermianThe term "Permian" was introduced into geology in 1841 by Sir Sir R. I. Murchison, president of the Geological Society of London, who identified typical strata in extensive Russian explorations undertaken with Edouard de Verneuil; Murchison asserted in 1841 that he named his "Permian...

    )
  12. The Emeishan Traps
    Emeishan Traps
    The Emeishan Traps constitute a flood basalt volcanic province, or large igneous province, in southwestern China, centered in Sichuan province. It is sometimes referred to as the Permian Emeishan Large Igneous Province or variations of that term....

     (western China)
  13. The Viluy traps
  14. The Pre-Devonian traps
  15. The Coppermine River Group (Canada) part of the larger 1,270 million year old (Mesoproterozoic
    Mesoproterozoic
    The Mesoproterozoic Era is a geologic era that occurred between 1600 Ma and 1000 Ma . The Mesoproterozoic was the first period of Earth's history with a respectable geological record. Continents existed in the Paleoproterozoic, but we know little about them...

    ) Mackenzie Large Igneous Province
    Mackenzie Large Igneous Province
    The Mackenzie Large Igneous Province is a major Mesoproterozoic large igneous province of the southwestern, western and northwestern Canadian Shield in Canada. It consists of a group of related igneous rocks that were formed during a massive igneous event starting about 1,270 million years ago...

  16. The Strand Fiord Formation
    Strand Fiord Formation
    The Strand Fiord Formation is a Late Cretaceous volcanic component, located on northwestern and west-central Axel Heiberg Island, Nunavut, Canada. The formation contains flood basalts which are found on western Axel Heiberg Island at Dragon Cliffs tall....

  17. The Chilcotin Group (south-central British Columbia, Canada)
  18. The North Mountain Basalt
    North Mountain (Nova Scotia)
    North Mountain is a narrow southwest-northeast trending volcanic mountain range on the mainland portion of southwestern Nova Scotia, stretching from Brier Island to Cape Split...


See also

  • Large igneous province
    Large igneous province
    A Large Igneous Province is an extremely large accumulation of igneous rocks—intrusive, extrusive, or both—in the earth's crust...

  • Oceanic plateau
    Oceanic plateau
    An oceanic plateau is a large, relatively flat submarine region that rises well above the level of the ambient seabed. While many oceanic plateaus are composed of continental crust, and often form a step interrupting the continental slope, some plateaus are undersea remnants of large igneous...

  • Supervolcano
    Supervolcano
    A supervolcano is a volcano capable of producing a volcanic eruption with an ejecta volume greater than 1,000 cubic kilometers . This is thousands of times larger than most historic volcanic eruptions. Supervolcanoes can occur when magma in the Earth rises into the crust from a hotspot but is...

  • Volcanic plateau
    Volcanic plateau
    A volcanic plateau is a plateau produced by volcanic activity. There are two main types: lava plateaus and pyroclastic plateaus.-Lava plateau:...