Volcanic Rock (Igneous)

Volcanic Rock (Igneous) Definition

A “Volcanic Rock” is an igneous rock that is finely crystalline and glassy (or aphanitic). To illustrate, volcanic rocks result from volcanic action at the earth’s surface. Typically, this also includes igneous intrusions that are “near-surface,” which may otherwise be considered plutonic. This action results in a final rock that is different in consistency, texture, and formation, comparing to other igneous rocks that crystalize underground. Moreover, most volcanic rocks are violently ejected or calmly extruded in the form of lava (liquid phase rock).

Examples of Volcanic Rock Types in Igneous Rock Classification

  • alkali-feldspar rhyolite
  • rhyolite (liparite)
  • dacite
  • quartz-alkali (-feldspar) trachyte
  • alkali (-feldspar) trachyte
  • foid-bearing alkali (-feldspar) trachyte
  • quartz trachyte
  • trachyte
  • foid-bearing trachyte
  • quartz latite
  • latite
  • foid-bearing latite
  • andesite
  • calc-alkaline andesite
  • andesite
  • mugearites
  • basalt
  • tephritic phonolite
  • phonolite tephrite (basanite)
  • tephrite
  • basanite
  • phonolitic foidite
  • tephritic foidite
  • foidite

Similar Posts

  • Fault Scarp

    ByGeo Forward

    Fault Scarp Fault Scarp: In the field of geology, a dip-slip fault scarp is a steep slope that is formed directly by fault movement. It occurs along the line of a normal fault, reverse fault, or transform fault. A fault scarp represents the planer surface of the fault before erosion and weathering modify it.

  • |

    Geologic Time Scale

    ByGeo Forward

    Geologic Time Scale The Geologic Time Scale is an international system used by geologists to classify and identify major geologic events and formations. The geologic timescale essentially categories the earth’s entire geologic (and biologic) history, within a series of defined eons, eras, periods, epochs, and ages. Updates & Maintenance The geologic time scale is continuously…

  • De-watering System

    ByGeo Forward

    De-Watering System in Methane Mitigation De-Watering: In accordance with the Los Angeles Department of Building and Safety (LADBS) Methane Code, Ordinance Number 175790, a de-watering system is a permanent water removal system in a methane mitigation system. In the mitigation process, a de-watering system consists of perforated horizontal pipes, gravel pockets, sump areas with pumps,…

  • Consistency

    ByGeo Forward

    Consistency The term “Consistency” in the fields of engineering geology and geotechnical engineering means the degree of adhesion between soil particles within a sample, that are observed to resist deformation or rupture.

  • Rock Stratigraphic Unit

    ByGeo Forward

    Rock Stratigraphic Unit In the field of geology, a rock stratigraphic unit, or a lithostratigraphic unit, is a geologic formation that is identifiable by a specific lithology, as well as a consistent stratigraphic position. For example, the Monterey Formation is a rock stratigraphic unit, as it tends to consistently comprise the same gravel and sand…

  • Silicates

    ByGeo Forward

    Silicates Definition In the fields of geology and mineralogy, the term “silicates” refers to compounds whose crystal structure contains SiO4 tetrahedra. Silicates are either isolated or joined to form groups, rings, single or double chains, sheets, or three-dimensional frameworks.