Banded gneiss with dike of granite orthogneiss

A dike or dyke in geology is a type of sheet intrusion referring to any geologic body that cuts discordantly across

• planar wall rock structures, such as bedding or foliation
• massive rock formations, like igneous/magmatic intrusions and salt diapirs. Geology (from Greek γη gê, "earth" and λόγος Logos, "speech" lit A diapir (ˈdaɪəpɪər) ( French, from Greek diapeirein, to pierce through is an Intrusion caused by Buoyancy and Pressure

Dikes can therefore be either intrusive or sedimentary in origin. In Geology, an intrusion is a body of Igneous rock that has Crystallized from molten Magma below the surface of the Earth. Sediment is any particulate matter that can be transported by fluid flow and which eventually is deposited as a layer of solid particles on the bed or bottom of a body of

Magmatic dikes

A small dike on the Baranof Cross-Island Trail, Alaska

Dikes in the Black Canyon of the Gunnison National Park, Colorado, USA

An intrusive dike is an igneous body with a very high aspect ratio, which means that its thickness is usually much smaller than the other two dimensions. The Baranof Cross-Island Trail is an informal trail located across Baranof Island, Alaska from the community of Sitka to Baranof Warm Springs Alaska ( Аляска Alyaska) is a state in the United States of America, in the northwest of the North American continent Igneous rocks (etymology from Latin ignis, fire are rocks formed by solidification of cooled Magma (molten rock The aspect ratio of a Shape is the ratio of its longer Dimension to its shorter dimension Thickness can vary from sub-centimeter scale to many meters and the lateral dimensions can extend over many kilometers. A dike is an intrusion into an opening cross-cutting fissure, shouldering aside other pre-existing layers or bodies of rock; this implies that a dike is always younger than the rocks that contain it. A fissure vent, also known as a volcanic fissure or simply fissure, is a linear Volcanic vent through which Lava erupts usually without any Dikes are usually high angle to near vertical in orientation, but subsequent tectonic deformation may rotate the sequence of strata through which the dike propagates so that the latter becomes horizontal. This article discusses the geologic usage for the philosophical or architectural usage see Architectonics ' Or see Plate tectonics. Near horizontal or conformable intrusions along bedding planes between strata are called intrusive sills. In Geology and related fields a stratum (plural strata) is a layer of rock or Soil with internally consistent characteristics that distinguishes In Geology, a sill is a tabular Pluton that has intruded between older layers of Sedimentary rock, beds of Volcanic

Sometimes dikes appear as swarms, consisting of several to hundreds of dikes emplaced more or less contemporaneously during a single intrusive event. The world's largest dike swarm is the Mackenzie dike swarm in the Northwest Territories, Canada. A dike swarm or dyke swarm in Geology is a major group of parallel linear or radially oriented dikes intruded within Continental crust The Mackenzie dike swarm, also called the Mackenzie dikes, form a Large igneous province in the western Canadian Shield of Canada. The Northwest Territories (ˌnɔrθˌwɛstˈtɛrɨtɔriz ( NWT or NT; French, les Territoires du Nord-Ouest) is a territory Country to "Dominion of Canada" or "Canadian Federation" or anything else please read the Talk Page ^[1]

Shiprock, New Mexico a volcanic neck in the distance, with radiating dike on its south side. Shiprock, ( Tsé Bit'a'í, "rock with wings" or "winged rock" is a rock formation rising nearly above the high-desert plain on the Navajo Nation New Mexico ( is a state located in the southwestern region of the United States of America. Photo credit: USGS Digital Data Series

Dikes often form as either radial or concentric swarms around plutonic intrusives, volcanic necks or feeder vents in volcanic cones. The United States Geological Survey ( USGS) is a scientific agency of the United States government. A volcanic plug, also called a volcanic neck or lava neck, is a volcanic landform created when Lava hardens within a Vent on Volcanic cones are among the simplest Volcano formations in the world The latter are known as ring dikes. A ring dike or ring dyke in Geology refers to an intrusive Igneous body

Dikes can vary in texture and their composition can range from diabase or basaltic to granitic or rhyolitic, but on a global perspective the basaltic composition prevails, manifesting ascent of vast volumes of mantle-derived magmas through fractured lithosphere throughout Earth history. Diabase (ˈdaɪəbeɪs or Dolerite is a Mafic, Holocrystalline, Igneous rock equivalent to Volcanic Basalt or plutonic Basalt (bəˈsɔːlt ˈbeisɔːlt ˈbæsɔːlt is a common Extrusive Volcanic rock. Granite (ˈɡrænɪt is a common and widely occurring type of intrusive, Felsic, igneous rock. This page is about a volcanic rock For the ghost town see Rhyolite Nevada, and for the satellite system see Rhyolite/Aquacade. Pegmatite dikes are extremely coarse crystalline granitic rocks often associated with late stage granite intrusions or metamorphic segregations. Pegmatite is a very coarse-grained Igneous rock that has a grain size of 20 mm or more such rocks are referred to as pegmatitic. Metamorphic rock is the result of the transformation of an existing rock type the protolith, in a process called Metamorphism, which means "change Aplite dikes are fine grained or sugary textured intrusives of granitic composition.

Sedimentary dikes

Sedimentary dikes or clastic dikes are vertical bodies of sedimentary rock that cut off other rock layers. A clastic dike is the geological term used to describe a seam of 'foreign' sedimentary material (often Breccia) that fills cracks in sedimentary strata They can form in two ways:

• When a shallow unconsolidated sediment is composed of alternating coarse grained and impermeable clay layers the fluid pressure inside the coarser layers may reach a critical value due to lithostatic overburden. Permeability in the Earth sciences (commonly symbolized as κ, or k) is a measure of the ability of a material (typically a rock or unconsolidated Clay is a naturally occurring material composed primarily of fine-grained Minerals which show plasticity through a variable range of Water content, and Fluid pressure is the Pressure at some point within a Fluid, such as water or air Overburden pressure, lithostatic pressure, and vertical stress are terms that denote the Pressure or stress imposed on a layer of Soil Driven by the fluid pressure the sediment breaks through overlying layers and forms a dike.
• When a soil is under permafrost conditions the pore water is totally frozen. This article is about frozen ground For other meanings see Permafrost (disambiguation. Groundwater is Water located beneath the Ground surface in Soil pore spaces and in the Fractures of lithologic formations When cracks are formed in such rocks, they may fill up with sediments that fall in from above. The result is a vertical body of sediment that cuts through horizontal layers: a dike.

Magmatic dikes radiating from West Spanish Peak

See also

• Batholith
• Ring dike
• Fissure vent
• Laccolith
• Runamo, formerly interpreted as a runic inscription. West Spanish Peak is a high mountain peak in the US state of Colorado. A batholith (from Greek bathos, depth + lithos, rock is a large emplacement of Igneous intrusive (also called plutonic rock that forms A ring dike or ring dyke in Geology refers to an intrusive Igneous body A fissure vent, also known as a volcanic fissure or simply fissure, is a linear Volcanic vent through which Lava erupts usually without any A laccolith is an Igneous intrusion (or concordant Pluton) that has been injected between two layers of Sedimentary rock. Runamo is a cracked Dolerite dike that was for centuries held to be a Runic inscription and gave rise to a famous scholarly controversy in the 19th century
• Dike swarm
• Sill

References