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

  • Environmental Geology

    ByGeo Forward

    Environmental Geology Environmental Geology: (en·vi·ron·men·tal ge·ol·o·gy) a branch of geology that relates to the impact of human activity on Earth, and the pollution of geologic formations, reserves, and resources. Common focus points of environmental geology are contaminated soil, groundwater aquifers, lakes, rivers, and the ocean. Professional geologists assess and remediate contamination plumes in all media,…

  • Reverse Fault Definition

    ByGeo Forward

    Reverse Fault Reverse Fault: In the field of geology, a reverse fault is a dip-slip fault in which the hanging wall moves upwards, relative to the footwall. The average dipping angle of a reverse fault ranges from 45 to 90 degrees. However, if less than 45 degrees, it becomes a “thrust fault.” Reverse faults are…

  • Volcanology

    ByGeo Forward

    Volcanology Volcanology: Volcanology is a branch of geology that focuses on the study of volcanos. In volcanology, geologists conduct field and laboratory investigations to learn about continental, coastal, and submarine volcanic activities. In fact, volcanology ties into many other branches of geology. For instance, a volcanologist may study the geochemistry of igneous rocks, such as…

  • Translational Slide Definition

    ByGeo Forward

    Translational Slide Landslide Translational Slide: In the seismology branch of geology, a translational slide is a type of landslide movement that occurs predominantly along a planar surface. Alternatively, this movement can occur along gently undulating surfaces. For instance, the Palona Schist metamorphic bedrock on the eastern embankment of the former St. Francis Dam comprises an…