Metamorf Rock

Definition
Metamorfosisme process is a process that causes changes in mineral composition, texture and structure on the rocks because of heat and high pressure, as well as the active chemical solution. The end result of the process metamorfisme is metamorphic rock. So rocks are igneous rocks formed by processes metamorfisme on pre-existing rocks. Rock (which had existed previously) can be igneous, sedimentary and metamorphic.

Mineral composition
    Compiler minerals metamorphic rocks can be divided into the minerals:

• Cube-shaped minerals: quartz, feldsfar, calcite, garnet and piroksin.
• Not a cube-shaped: mica, chlorite, amphiboles (hornblende), hematite, graphite and minerals talk.Susunan (Fabrik)

    From the appearance of three-dimensional, Fabrik can be divided into:

• Isotropic: the composition of the grain in all directions look the same.
• Anisotropic: the appearance of the composition of mineral grains are not the same in all directions.

Texture
    Based on mineral grain size, can be differentiated into:

• Fanaretik: grains large enough to be recognized with the naked eye.
• Afanitik: grains are too small to be recognized with the naked eye.

Structure
    Structures in metamorphic rocks known there are three:

• Granular: if the grains interlock minerla related (inter-locking).
• Foliasi: when the minerals form a series of flat surfaces subparalel.
• Lineasi: if the minerals formed prismatic appearance at the juxtaposition of rocks, such as a pencil grip.

In nature, the rocks which have only very rarely lineasi structure, and most other berlineasi foliasi also formed. Foliasi may be irregular, curved or folded when deformed.