Chapter 25, Problem 15TE

Each of the following statements describes one or more characteristics of a particular metamorphic rock. For each statement, name the metamorphic rock being described.

a) Foliated rock, sometimes derived from granite

b) Hard, nonfoliated, single-mineral, formed under high-to-moderate pressure

c) Foliated rock, possessing excellent rock cleavage; generally used in making blackboards

d) Non-foliated rock composed of carbonate minerals

e) Foliated rock containing $50\%$ platy minerals; named according to the major minerals in the rock

To determine

The type of metamorphic rock.

Answer to Problem 15TE

The type of metamorphic rock is Gneiss.

Explanation of Solution

When the mass of the rock comes in contact with the change in temperature and pressure, it gets transformed. This is known as metamorphism.

Recrystallization of the particles and mineral takes place in the rock, which gives them unique characteristics. When the rock is subjected to pressure, some of its composites get realigned into parallel planes. This leads to a foliated appearance to the rock. Gneiss is a foliated rock that can be derived from granite. This happened under very high pressure when the minerals readjust into dark and light streaks.

Conclusion:

Therefore, the type of metamorphic rock is Gneiss.

To determine

The type of metamorphic rock.

Answer to Problem 15TE

The type of metamorphic rock is Quartzite.

Explanation of Solution

When the rock comes in contact with temperature and pressure variation, a change in their appearance takes place. This process is known as metamorphism.

Metamorphic rocks are defined by their appearance and comprising minerals. Quartzite is a hard, non-foliated, single-mineral, formed under high-to-moderate pressure. It is formed from metamorphosed quartz sandstone, which makes it very hard. Pure quartzite is white in color, but due to impurity, it can vary like pink, green, and many more.

Conclusion:

Therefore, the type of metamorphic rock is Quartzite.

To determine

The type of metamorphic rock.

Answer to Problem 15TE

The type of metamorphic rock is Slate.

Explanation of Solution

Slate is a type of lowest grade foliated metamorphic rock, and it is formed under low temperature. It is made up of very tiny particles and mica flakes and is a metamorphosed shale. It has excellent rock cleavage that is why it is used for making blackboards and pool table. It can be split into thin slabs.

Conclusion:

Therefore, the type of metamorphic rock is Slate.

To determine

The type of metamorphic rock.

Answer to Problem 15TE

The type of metamorphic rock is Marble.

Explanation of Solution

Metamorphic rocks are formed due to the change in temperature and pressure. Due to these conditions, rocks get their unique characteristics. Marble is a crystalline type of metaphoric rock that is metamorphosed from limestone. It is purely white in color due to the presence of calcite. It is soft in nature and is mostly used for constructing a building. Many times, it gets color like green, gray, pink due to the presence of impurities.

Conclusion:

Therefore, the type of metamorphic rock is Marble.

To determine

The type of metamorphic rock.

Answer to Problem 15TE

The type of metamorphic rock is Schist.

Explanation of Solution

Schist is a type of metamorphic rock that can be recognized very easily due to its shiny nature. It is formed under high temperature, and this heat allows the mineral to grow bigger, such that it is visible with naked eyes. Schist is a foliated rock containing $50\%$ platy minerals and is named according to the major minerals in the rocks.

Conclusion:

Therefore, the type of metamorphic rock is Schist.