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What are Metamorphic Rocks

Metamorphic rock creates a zebra striped sample in the canyon partitions of Marble Canyon. Death Valley National Park, California and Nevada. NPS image through Dan Kish.

Metamorphic Rocks

Metamorphic rocks structure when excessive temperatures and stress act on a rock to alter its bodily and chemical homes (metamorphism skill 'to alternate form'). These stipulations regularly stretch, twist and fold the rock as it cools. In metamorphic rocks some or all of the minerals in the authentic rock are replaced, atom by means of atom, to structure new minerals. Types of metamorphic rocks consist of gneiss, quartzite, marble, schist, soapstone, and phyllite.

Related: Do you Know What it is Plate Tectonics

Parks with examples of metamorphic rocks include

  • Catoctin Mountain Park, Maryland
  • Death Valley National Park, California and Nevada
  • Grand Teton National Park, Wyoming
  • Rocky Mountain National Park, Colorado
  • Shenandoah National Park, Virginia

Key Terms

  1. Contact Metamorphism: A kind of local, thermal metamorphism prompted with the aid of the intrusion and extrusion of magmas; takes vicinity in rocks at or close to their contact with a physique of igneous rock.
  2. Parent Rock: Rock from which soil, sediment, or different rock is derived.
  3. Regional Metamorphism: A kind of metamorphism that influences a widespread region, as antagonistic to nearby metamorphism that is tremendous solely in an especially restrained area.

Foliated Metamorphic Rocks

As stress squeezes on a father or mother rock at some point of recrystallization it motivates the platy or elongated minerals inside the rock to end up aligned, or foliated. Foliated rocks boost a platy or sheet-like shape that displays the path that strain was once utilized in. Types of foliated metamorphic rocks consist of slate, schist, and gneiss. Gneiss archives the historical beginnings of the Appalachian Mountain belt at:

What are Metamorphic Rocks
- Foliated metamorphic gneiss.
- Photograph by using Tim Connors
  1. Antietam National Battlefield, Maryland
  2. Chesapeake and Ohio Canal National Historical Park, District of Columbia, Maryland, amd West Virginia
  3. Harpers Ferry National Historical Park, West Virginia, Virginia, and Maryland

Non-foliated Metamorphic Rocks

Not all mum or dad rocks have platy or elongated minerals and when these rocks bear metamorphism the character mineral grains do not align. Types of non-foliated metamorphic rocks encompass marble, quartzite and hornfels. Soapstone was once used by using the American Indians for equipment and implements, and is determined in:

What are Metamorphic Rocks
- Non-foliated metamorphic soapstone.
- Photo courtesy of Tina Kuhn
  • Rock Creek Park, District of Columbia

Extensive quartzite deposits are regularly occurring from:

  • City of Rocks National Reserve, Idaho