A report on Lava

10 m lava fountain in Hawaii, United States
Lava flow during a rift eruption at Krafla, Iceland in 1984
Pāhoehoe and ʻaʻā lava flows side by side in Hawaii, September 2007
Toes of a pāhoehoe advance across a road in Kalapana on the east rift zone of Kīlauea Volcano in Hawaii, United States
Columnar jointing in Giant's Causeway in Northern Ireland
Lava entering the sea to expand the big island of Hawaii, Hawaii Volcanoes National Park
Lava enters the Pacific at the Big Island of Hawaii
Glowing aā flow front advancing over pāhoehoe on the coastal plain of Kilauea in Hawaii, United States
Pāhoehoe lava from Kīlauea volcano, Hawaii, United States
Block lava at Fantastic Lava Beds near Cinder Cone in Lassen Volcanic National Park
Pillow lava on the ocean floor near Hawaii
Arenal Volcano, Costa Rica, is a stratovolcano.
A forested lava dome in the midst of the Valle Grande, the largest meadow in the Valles Caldera National Preserve, New Mexico, United States
Shiprock, New Mexico, United States: a volcanic neck in the distance, with a radiating dike on its south side
450 m-high lava fountain at Kilauea
Lava can easily destroy entire towns. This picture shows one of over 100 houses destroyed by the lava flow in Kalapana, Hawaii, United States, in 1990.

Molten or partially molten rock that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface.

- Lava
10 m lava fountain in Hawaii, United States

58 related topics with Alpha

Overall
Bromo volcano in Indonesia. This country has more than 130 active volcanoes, one of which is a supervolcano, making Indonesia the country with the most active volcanoes in the world.

Volcano

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Bromo volcano in Indonesia. This country has more than 130 active volcanoes, one of which is a supervolcano, making Indonesia the country with the most active volcanoes in the world.
Cordillera de Apaneca volcanic range in El Salvador. The country is home to 170 volcanoes, 23 which are active, including two calderas, one being a supervolcano. El Salvador has earned the epithets endearment La Tierra de Soberbios Volcanes, (The Land of Magnificent Volcanoes).
Sabancaya volcano erupting, Peru in 2017
Cleveland Volcano in the Aleutian Islands of Alaska photographed from the International Space Station, May 2006
An eruption of Mount Pinatubo on June 12, 1991, three days before its climactic eruption
Fountain of lava erupting from a volcanic cone in Hawaii, 1983
Aerial view of the Barren Island, Andaman Islands, India, during an eruption in 1995. It is the only active volcano in South Asia.
Map showing the divergent plate boundaries (oceanic spreading ridges) and recent sub-aerial volcanoes (mostly at convergent boundaries)
Lakagigar fissure vent in Iceland, the source of the major world climate alteration of 1783–84, has a chain of volcanic cones along its length.
Skjaldbreiður, a shield volcano whose name means "broad shield"
Izalco volcano, the youngest volcano in El Salvador. Izalco erupted almost continuously from 1770 (when it formed) to 1958, earning it the nickname of "Lighthouse of the Pacific".
Cross-section through a stratovolcano (vertical scale is exaggerated):
Satellite images of the 15 January 2022 eruption of Hunga Tonga-Hunga Haʻapai
Pāhoehoe lava flow on Hawaii. The picture shows overflows of a main lava channel.
The Stromboli stratovolcano off the coast of Sicily has erupted continuously for thousands of years, giving rise to its nickname "Lighthouse of the Mediterranean"
Columnar-jointed basalt lava erupted from a volcano, South Penghu Marine National Park in Taiwan
Light-microscope image of tuff as seen in thin section (long dimension is several mm): The curved shapes of altered glass shards (ash fragments) are well preserved, although the glass is partly altered. The shapes were formed around bubbles of expanding, water-rich gas.
Fresco with Mount Vesuvius behind Bacchus and Agathodaemon, as seen in Pompeii's House of the Centenary
Narcondam Island, India, is classified as a dormant volcano by the Geological Survey of India
Fourpeaked volcano, Alaska, in September 2006 after being thought extinct for over 10,000 years
Mount Rinjani eruption in 1994, in Lombok, Indonesia
Shiprock in New Mexico, US
Capulin Volcano National Monument in New Mexico, US
Koryaksky volcano towering over Petropavlovsk-Kamchatsky on Kamchatka Peninsula, Far Eastern Russia
Schematic of volcano injection of aerosols and gases
Solar radiation graph 1958–2008, showing how the radiation is reduced after major volcanic eruptions
Sulfur dioxide concentration over the Sierra Negra Volcano, Galapagos Islands, during an eruption in October 2005
Comparison of major United States supereruptions (VEI 7 and 8) with major historical volcanic eruptions in the 19th and 20th century. From left to right: Yellowstone 2.1 Ma, Yellowstone 1.3 Ma, Long Valley 6.26 Ma, Yellowstone 0.64 Ma . 19th century eruptions: Tambora 1815, Krakatoa 1883. 20th century eruptions: Novarupta 1912, St. Helens 1980, Pinatubo 1991.
The Tvashtar volcano erupts a plume 330 km (205 mi) above the surface of Jupiter's moon Io.
Olympus Mons (Latin, "Mount Olympus"), located on the planet Mars, is the tallest known mountain in the Solar System.

A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.

Lava flow on Hawaii. Lava is the extrusive equivalent of magma.

Magma

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Molten or semi-molten natural material from which all igneous rocks are formed.

Molten or semi-molten natural material from which all igneous rocks are formed.

Lava flow on Hawaii. Lava is the extrusive equivalent of magma.
Phase diagram for the diopside-anorthite system
Schematic diagrams showing the principles behind fractional crystallisation in a magma. While cooling, the magma evolves in composition because different minerals crystallize from the melt. 1: olivine crystallizes; 2: olivine and pyroxene crystallize; 3: pyroxene and plagioclase crystallize; 4: plagioclase crystallizes. At the bottom of the magma reservoir, a cumulate rock forms.
A single silica tetrahedron
Two silica tetrahedra joined by a bridging oxygen ion (tinted pink)

Following its ascent through the crust, magma may feed a volcano and be extruded as lava, or it may solidify underground to form an intrusion, such as a dike, a sill, a laccolith, a pluton, or a batholith.

Rhyolite

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Most silica-rich of volcanic rocks.

Most silica-rich of volcanic rocks.

QAPF diagram with rhyolite field highlighted
TAS diagram with rhyolite field highlighted

This favors explosive eruptions over effusive eruptions, so rhyolitic magma is more often erupted as pyroclastic rock than as lava flows.

Mount Rainier, a 14411 ft stratovolcano, the highest point in the US state of Washington

Stratovolcano

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Mount Rainier, a 14411 ft stratovolcano, the highest point in the US state of Washington
Exposed internal structure of alternating layers of lava and pyroclastic rock in the eroded Broken Top stratovolcano in Oregon
Cross-section of subduction zone and associated stratovolcanoes
Mount Etna on the island of Sicily, in southern Italy
Snow-like blanket of Mount Pinatubo's ashfall deposits in a parking lot on Clark Air Base (June 15, 1991)
Mayon Volcano extruding lava flows during its eruption on December 29, 2009
Paluweh eruption as seen from space

A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava and tephra.

Mauna Loa, a shield volcano in Hawaii

Shield volcano

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Type of volcano named for its low profile, resembling a warrior's shield lying on the ground.

Type of volcano named for its low profile, resembling a warrior's shield lying on the ground.

Mauna Loa, a shield volcano in Hawaii
An Ancient Greek warrior's shield–its circular shape and gently sloping surface, with a central raised area, is a shape shared by many shield volcanoes
Skjaldbreiður is a shield volcano in Iceland, whose name means broad shield in Icelandic.
Scaled image showing Olympus Mons, top, and the Hawaiian island chain, bottom. Martian volcanoes are far larger than those found on Earth.
{{okina}}A{{okina}}a advances over solidified pāhoehoe on Kīlauea, Hawai{{okina}}i
A pāhoehoe lava fountain on Kīlauea erupts
A lava lake in the caldera of Erta Ale, an active shield volcano in Ethiopia
Pāhoehoe flows enter the Pacific Ocean on Hawai{{okina}}i island
Puʻu ʻŌʻō, a parasitic cinder cone on Kīlauea, lava fountaining at dusk in June 1983, near the start of its eruptive cycle
Nāhuku, a famous lava tube on Hawai{{okina}}i island, now a tourist attraction in the Hawaiʻi Volcanoes National Park

It is formed by the eruption of highly fluid (low viscosity) lava, which travels farther and forms thinner flows than the more viscous lava erupted from a stratovolcano.

Basalt

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QAPF diagram with basalt/andesite field highlighted in yellow. Basalt is distinguished from andesite by SiO2 < 52%.
Basalt is field B in the TAS classification.
Vesicular basalt at Sunset Crater, Arizona. US quarter (24mm) for scale.
Columnar basalt flows in Yellowstone National Park, USA
Columnar basalt at Szent György Hill, Hungary
Large masses must cool slowly to form a polygonal joint pattern, as here at the Giant's Causeway in Northern Ireland
Columns of basalt near Bazaltove, Ukraine
Photomicrograph of a thin section of basalt from Bazaltove, Ukraine
An active basalt lava flow
The Giant's Causeway in Northern Ireland
Columnar jointed basalt in Turkey
Columnar basalt at Cape Stolbchaty, Russia
Pillow basalts on the Pacific seafloor
Paraná Traps, Brazil
Lunar olivine basalt collected by Apollo 15 astronauts
Kaolinized basalt near Hungen, Vogelsberg, Germany
Metamorphosed basalt from an Archean greenstone belt in Michigan, US. The minerals that gave the original basalt its black colour have been metamorphosed into green minerals.
The Code of Hammurabi was engraved on a 2.25m tall basalt stele in around 1750 BC.

Basalt is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the surface of a rocky planet or moon.

Some of the eruptive structures formed during volcanic activity (counterclockwise): a Plinian eruption column, Hawaiian pahoehoe flows, and a lava arc from a Strombolian eruption

Types of volcanic eruptions

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Some of the eruptive structures formed during volcanic activity (counterclockwise): a Plinian eruption column, Hawaiian pahoehoe flows, and a lava arc from a Strombolian eruption
Diagram showing the scale of VEI correlation with total ejecta volume
Diagram of a Hawaiian eruption. (key: 1. Ash plume 2. Lava fountain 3. Crater 4. Lava lake 5. Fumaroles 6. Lava flow 7. Layers of lava and ash 8. Stratum 9. Sill 10. Magma conduit 11. Magma chamber 12. Dike) [[:File:Hawaiian Eruption-numbers.svg|Click for larger version]].
Ropey pahoehoe lava from Kilauea, Hawaii
Diagram of a Strombolian eruption. (key: 1. Ash plume 2. Lapilli 3. Volcanic ash rain 4. Lava fountain 5. Volcanic bomb 6. Lava flow 7. Layers of lava and ash 8. Stratum 9. Dike 10. Magma conduit 11. Magma chamber 12. Sill) [[:File:Strombolian Eruption-numbers.svg|Click for larger version]].
An example of the lava arcs formed during Strombolian activity. This image is of Stromboli itself.
Diagram of a Vulcanian eruption. (key: 1. Ash plume 2. Lapilli 3. Lava fountain 4. Volcanic ash rain 5. Volcanic bomb 6. Lava flow 7. Layers of lava and ash 8. Stratum 9. Sill 10. Magma conduit 11. Magma chamber 12. Dike) [[:File:Vulcanian Eruption-numbers.svg|Click for larger version.]]
Tavurvur in Papua New Guinea erupting
Diagram of Peléan eruption. (key: 1. Ash plume 2. Volcanic ash rain 3. Lava dome 4. Volcanic bomb 5. Pyroclastic flow 6. Layers of lava and ash 7. Stratum 8. Magma conduit 9. Magma chamber 10. Dike) [[:File:Pelean Eruption-numbers.svg|Click for larger version]].
Diagram of a Plinian eruption. (key: 1. Ash plume 2. Magma conduit 3. Volcanic ash rain 4. Layers of lava and ash 5. Stratum 6. Magma chamber) [[:File:Plinian Eruption-numbers.svg|Click for larger version]].
21 April 1990 eruptive column from Redoubt Volcano, as viewed to the west from the Kenai Peninsula
Lahar flows from the 1985 eruption of Nevado del Ruiz, which totally destroyed Armero in Colombia
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Diagram of a Surtseyan eruption. (key: 1. Water vapor cloud 2. Compressed ash 3. Crater 4. Water 5. Layers of lava and ash 6. Stratum 7. Magma conduit 8. Magma chamber 9. Dike) [[:File:Surtseyan Eruption-numbers.svg|Click for larger version]].
Diagram of a Submarine eruption. (key: 1. Water vapor cloud 2. Water 3. Stratum 4. Lava flow 5. Magma conduit 6. Magma chamber 7. Dike 8. Pillow lava) [[:File:Submarine Eruption-numbers.svg|Click to enlarge]].
A diagram of a Subglacial eruption. (key: 1. Water vapor cloud 2. Crater lake 3. Ice 4. Layers of lava and ash 5. Stratum 6. Pillow lava 7. Magma conduit 8. Magma chamber 9. Dike) [[:File:Subglacial Eruption-numbers.svg|Click for larger version]].
Herðubreið, a tuya in Iceland
Diagram of a phreatic eruption. (key: 1. Water vapor cloud 2. Magma conduit 3. Layers of lava and ash 4. Stratum 5. Water table 6. Explosion 7. Magma chamber)
Pyroclastic flows at Mayon Volcano, Philippines, 1984
The lava spine that developed after the 1902 eruption of Mount Pelée
Mount Lamington following the devastating 1951 eruption
Surtsey, erupting 13 days after breaching the water. A tuff ring surrounds the vent.
The fissure formed by the 1886 eruption of Mount Tarawera, an example of a fracture zone eruption

Several types of volcanic eruptions—during which lava, tephra (ash, lapilli, volcanic bombs and volcanic blocks), and assorted gases are expelled from a volcanic vent or fissure—have been distinguished by volcanologists.

Rhyolitic lava dome of Chaitén Volcano during its 2008–2010 eruption

Lava dome

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Rhyolitic lava dome of Chaitén Volcano during its 2008–2010 eruption
One of the Inyo Craters, an example of a rhyolite dome
Nea Kameni seen from Thera, Santorini
Lava domes in the crater of Mount St. Helens
The bulging cryptodome of Mt. St. Helens on April 27, 1980
Soufrière Hills lava spine before the 1997 eruption
Chao dacite coulée flow-domes (left center), northern Chile, viewed from Landsat 8

In volcanology, a lava dome is a circular mound-shaped protrusion resulting from the slow extrusion of viscous lava from a volcano.

Komatiite lava at the type locality in the Komati Valley, Barberton Mountainland, South Africa, showing the distinctive "spinifex texture" formed by dendritic plates of olivine (scale shown by a hammer on the right edge of photo)

Komatiite

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Komatiite lava at the type locality in the Komati Valley, Barberton Mountainland, South Africa, showing the distinctive "spinifex texture" formed by dendritic plates of olivine (scale shown by a hammer on the right edge of photo)
Komatiite sample collected from the Abitibi greenstone belt near Englehart, Ontario, Canada. Specimen is 9 cm wide. Bladed olivine crystals are visible, though spinifex texture is weak or absent in this sample.
Graph of komatiite geochemistry MgO% vs Cr ppm, from basal flows, Wannaway, Western Australia
Photomicrograph of a thin section of komatiite showing spinifex texture of pyroxene needle-like crystals
A2 facies dendritic feathery olivine crystals, drill hole WDD18, Widgiemooltha, Western Australia
A3 facies bladed olivine spinifex, drill hole WDD18, Widgiemooltha Komatiite, Western Australia

Komatiite is a type of ultramafic mantle-derived volcanic rock defined as having crystallised from a lava of at least 18 wt% MgO.

Pillow lava on the ocean floor of Hawaii

Pillow lava

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Pillow lava on the ocean floor of Hawaii
Pillow lava near Oamaru, New Zealand
Weathered Archean pillow lava in the Temagami Greenstone Belt of the Canadian Shield
Pillow lava formations from an ophiolite sequence, Northern Apennines, Italy
Pillow lava at Boatman's Harbour near Oamaru, New Zealand.

Pillow lavas are lavas that contain characteristic pillow-shaped structures that are attributed to the extrusion of the lava underwater, or subaqueous extrusion.