The magma in a dike may or may not have reached the surface. If the magma pours out onto the surface then it becomes a volcanic or extrusive rock. All extrusive rocks must of necessity have intrusive feeders, usually dikes or plugs. Colorado is home to examples of every type of known dike structure.
http://coloradogeologicalsurvey.org/colorado-geology/igneous-rocks/plutonic-rocks/dikes/
The magma in a dike may or may not have reached the surface. If the magma pours out onto the surface then it becomes a volcanic or extrusive rock. All extrusive rocks must of necessity have intrusive feeders, usually dikes or plugs.
http://coloradogeologicalsurvey.org/colorado-geology/igneous-rocks/plutonic-rocks/dikes/
Dikes are formed when magma (a mixture of molten material and crystals) rises from below and cuts across pre-existing strata. The magma may follow pre-existing cracks or faults, or may create its own path upward.
http://coloradogeologicalsurvey.org/colorado-geology/igneous-rocks/plutonic-rocks/dikes/
The magma crystallizes underground and becomes a dike, which is a plutonic or intrusive rock. Erosion cuts into the earth and allows us to observe the dikes. The magma in a dike may or may not have reached the surface. If the magma pours out onto the surface then it becomes a volcanic or extrusive rock.
http://coloradogeologicalsurvey.org/colorado-geology/igneous-rocks/plutonic-rocks/dikes/
Dikes. Dikes are formed when magma (a mixture of molten material and crystals) rises from below and cuts across pre-existing strata. The magma may follow pre-existing cracks or faults, or may create its own path upward.
http://coloradogeologicalsurvey.org/colorado-geology/igneous-rocks/plutonic-rocks/dikes/
In earth science, a dike is the channel (or fissure in the earth) through which magma is flowing up under pressure toward the surface. Dikes tend to widen in the direction of least resistance. They may be actively injected with magma even when there is no apparent volcanic activity at the surface.
https://answers.yahoo.com/question/index?qid=20081113151345AAjDeIF
An active dike is a body of magma moving through a sheet-like, vertical or nearly vertical fracture. An important aspect of magma flow not dealt with in the gelatin activity is the heat lost during eruption. Magma, ascending as a dike begins to cool and solidify and the flow may become localized in the dike.
https://answers.yahoo.com/question/index?qid=20081113151345AAjDeIF
When the magma solidifies, a dike forms. Dikes cut across rock layers rather than lying parallel to the rock layers. Dikes are common in areas of volcanic activity.
http://www.answers.com/Q/What_is_a_dike
Best Answer: Some previous answers fail to mention that by definition, a dike is a sheet-like intrusive igneous rock body which cuts across adjacent rock layers. A sill, is a similar body of intrusive igneous rock which intrudes along adjacent rock layers. Dikes and sills are commonly associated with volcanoes.
https://answers.yahoo.com/question/index?qid=20081113151345AAjDeIF
When magmas reach the surface of the Earth they erupt from a vent called a volcano. They may erupt explosively or non-explosively. 1  Non-explosive eruptions are favored by low gas content and low viscosity magmas (basaltic to andesitic magmas and sometimes rhyolitic magma).
http://www.tulane.edu/~sanelson/eens1110/igneous.htm
what is a magma dike
A dike is the channel through which magma is flowing up under pressure toward the surface. A dike is the channel or fissure in the earth through which magma is flowing up under pressure toward the surface.