What is metamorphic foliation quizlet?

What is metamorphic foliation quizlet?

metamorphic foliation (p.235) the parallel alignment of platy minerals (such as mica) and/ or the presence of alternating, light-colored and dark colored layers. metamorphic grade (p.245) a somewhat informal way to indicate the intensity of metamorphism, meaning the amount of degree of metamorphic change.

What are some examples of foliation in a metamorphic rock?

A rock list of types of foliated metamorphic specimens includes gneiss, schist, phyllite and slate. Specific patterns of foliation depend on the types of minerals found in the original rock, the size of the mineral grains and the way pressure is applied to the rock during metamorphosis.

Does this metamorphic rock have foliation?

Schist is a metamorphic rock with well-developed foliation. It often contains significant amounts of mica which allow the rock to split into thin pieces. It is a rock of intermediate metamorphic grade between phyllite and gneiss.

Why is foliation common in metamorphic rocks formed by regional metamorphism?

Figure 2. A foliated metamorphic rock. Rocks change during metamorphism because the minerals need to be stable under the new temperature and pressure conditions. Extreme pressure may also lead to foliation, the flat layers that form in rocks as the rocks are squeezed by pressure (figure 2).

What is foliation quizlet?

What is foliation? The planar (nearly flat) arrangement of mineral grains or crystals within a rock.

Which of the following is not an example of foliation in a metamorphic rock?

Some examples of non-foliated metamorphic rocks are marble, quartzite, and hornfels. Marble is metamorphosed limestone.

What causes foliation?

How Foliation Develops. When a rock is acted upon by pressure that is not the same in all directions, or by shear stress (forces acting to “smear” the rock), minerals can become elongated in the direction perpendicular to the main stress. The pattern of aligned crystals that results is called foliation.

What do you mean by foliation?

foliation, planar arrangement of structural or textural features in any rock type but particularly that resulting from the alignment of constituent mineral grains of a metamorphic rock of the regional variety along straight or wavy planes.

What is foliation and what causes it?

Foliation is caused by the re-alignment of minerals when they are subjected to high pressure and temperature. Individual minerals align themselves perpendicular to the stress field such that their long axes are in the direction of these planes (which may look like the cleavage planes of minerals).

What are foliated and non – foliated rocks?

Foliated metamorphic rocks such as gneiss , phyllite, schist, and slate have a layered or banded appearance that is produced by exposure to heat and directed pressure. Non-foliated metamorphic rocks such as hornfels, marble , quartzite, and novaculite do not have a layered or banded appearance.

What is the difference between foliated and Nonfoliated?

The major differences between foliated and nonfoliated metamorphic rocks are in the areas of texture, appearance and the type of pressure applied during recrystallization. The pressure applied to the reforming rock causes the differences in the way the rock looks once recrystallized and determines whether it will be foliated or nonfoliated.

What is an example of a foliated rock?

Foliated rock is a product of differential stress that deforms the rock in one plane, sometimes creating a plane of cleavage. For example, slate is a foliated metamorphic rock, originating from shale. Non-foliated rock does not have planar patterns of strain.

What is the highest grade metamorphic rock?

Metamorphic Rocks. The next higher grade rock, phyllite, contains grains that are still too small to see easily, but are coarse enough to catch light and so impart a sheen to the rock. Schist, the next higher grade rock, typically contains easily visible crystals of muscovite or biotite. Gneiss, the highest grade metamorphic rock,…