"Volcanics" redirects here. For Volcanic pistols, see Volcanic Repeating Arms.
For the album, see Volcanic Rock (album).
Ignimbrite, a volcanic rock deposited by pyroclastic flows
Volcanic rocks (often shortened to volcanics in scientific contexts) are rocks formed from lava erupted from a volcano. Like all rock types, the concept of volcanic rock is artificial, and in nature volcanic rocks grade into hypabyssal and metamorphic rocks and constitute an important element of some sediments and sedimentary rocks. For these reasons, in geology, volcanics and shallow hypabyssal rocks are not always treated as distinct. In the context of Precambrian shield geology, the term "volcanic" is often applied to what are strictly metavolcanic rocks. Volcanic rocks and sediment that form from magma erupted into the air are called "pyroclastics," and these are also technically sedimentary rocks.
Volcanic rocks are among the most common rock types on Earth's surface, particularly in the oceans. On land, they are very common at plate boundaries and in flood basalt provinces. It has been estimated that volcanic rocks cover about 8% of the Earth's current land surface.[1]
^Wilkinson, Bruce H; McElroy, Brandon J; Kesler, Stephen E; Peters, Shanan E; Rothman, Edward D (2008). "Global geologic maps are tectonic speedometers—Rates of rock cycling from area-age frequencies". Geological Society of America Bulletin. 121 (5–6): 760–79. Bibcode:2009GSAB..121..760W. doi:10.1130/B26457.1.
Volcanic rocks (often shortened to volcanics in scientific contexts) are rocks formed from lava erupted from a volcano. Like all rock types, the concept...
metamorphic rock, and sedimentary rock. Adakite – Volcanicrock type Andesite – Type of volcanicrock Alkali feldspar granite – Type of igneous rock rich in...
much finer-grained, often resembling volcanicrock. Hypabyssal rocks are less common than plutonic or volcanic rocks and often form dikes, sills, laccoliths...
Extrusive rock refers to the mode of igneous volcanicrock formation in which hot magma from inside the Earth flows out (extrudes) onto the surface as...
laccoliths, and volcanic necks. Intrusion is one of the two ways igneous rock can form. The other is extrusion, such as a volcanic eruption or similar...
A volcanic plug, also called a volcanic neck or lava neck, is a volcanic object created when magma hardens within a vent on an active volcano. When present...
Volcanic ash consists of fragments of rock, mineral crystals, and volcanic glass, produced during volcanic eruptions and measuring less than 2 mm (0.079 inches)...
are clastic rocks composed of rock fragments produced and ejected by explosive volcanic eruptions. The individual rock fragments are known as pyroclasts...
disordered array of liquid. Volcanic glass may refer to the interstitial material, or matrix, in an aphanitic (fine-grained) volcanicrock, or to any of several...
stoner rock with the relentlessly spiralling outro". Buffalo's 1973 sophomore release VolcanicRock has been "heralded as the first great stoner rock record...
rock made of volcanic ash ejected from a vent during a volcanic eruption. Following ejection and deposition, the ash is lithified into a solid rock....
crevices in the rock. All of these processes, illustrated by serpentinization, are an important part of the destruction of volcanicrock. The role of water...
Morro Rock (Salinan: Le'samo; Chumash: Lisamu'; Spanish: El Morro) is a volcanic plug in Morro Bay, California, on the Pacific Coast at the entrance to...
titanium, whose content is low in volcanic arc rocks. Because volcanicrock is easily weathered and eroded, older volcanic arcs are seen as plutonic rocks...
rock, although sometimes used as a synonym, normally now refers specifically to a high-silica-content (greater than 63% SiO2 by weight) volcanicrock...
Vesicular texture is a volcanicrock texture characterized by a rock being pitted with many cavities (known as vesicles) at its surface and inside. This...
Сибирские траппы, romanized: Sibirskiye trappy) is a large region of volcanicrock, known as a large igneous province, in Siberia, Russia. The massive...
Metavolcanic rock is volcanicrock that shows signs of having experienced metamorphism. In other words, the rock was originally produced by a volcano...
Scoria is a pyroclastic, highly vesicular, dark-colored volcanicrock formed by ejection from a volcano as a molten blob and cooled in the air to form...
pumicite in its powdered or dust form, is a volcanicrock that consists of highly vesicular rough-textured volcanic glass, which may or may not contain crystals...
is dominated by volcanicrock. The Canary Islands and some seamounts to the north-east form the Canary Volcanic Province, whose volcanic history started...
the rock, causing volcanism and creating new oceanic crust. Most divergent plate boundaries are at the bottom of the oceans, and so most volcanic activity...
amendment. Rhyolite is an extrusive igneous rock, formed from magma rich in silica that is extruded from a volcanic vent to cool quickly on the surface rather...
very near the surface of a rocky planet or moon. More than 90% of all volcanicrock on Earth is basalt. Rapid-cooling, fine-grained basalt is chemically...
lava, from volcanic craters or vents. Volcanic gases can also be emitted through groundwater heated by volcanic action. The sources of volcanic gases on...
This is a list of volcanic eruptions in the 21st century with a volcanic explosivity index (VEI) of 4 or higher, and smaller eruptions that resulted in...
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