Rock Classification and Properties

The video tutorial covers the classification of rocks based on mineral composition, color, and texture. It explains how geologists use these characteristics to identify rocks, with a focus on the role of silica content in determining rock color. The tutorial also discusses the importance of texture and grain size in rock classification, as well as the different shapes and angularities of grains. Finally, it introduces the three main types of rocks: igneous, sedimentary, and metamorphic, and explains their formation processes.

What are the three main characteristics used by geologists to classify rocks?

• Temperature, pressure, and volume

• Color, texture, and mineral composition

• Weight, size, and shape

• Age, location, and density

Which type of rock is typically light-colored and high in silica content?

• Basalt

• Sandstone

• Granite

• Limestone

What term is used to describe rocks with large, easily visible grains?

• Medium-grained

• Smooth-grained

• Coarse-grained

• Fine-grained

How do geologists refer to the small particles that make up most rocks?

• Pebbles

• Grains

• Fragments

• Crystals

What is the term for rocks with jagged grain shapes?

• Angular

• Rounded

• Smooth

• Flat

Which pattern is characterized by grains lying flat in layers?

• Banding

• Random

• Layering

• Swirling

What type of rock forms from cooling magma?

• Sedimentary

• Metamorphic

• Igneous

• Organic

Which rock type is formed from compressed sediments and remains of plants and animals?

• Metamorphic

• Sedimentary

• Volcanic

• Igneous

What process changes existing rock into metamorphic rock?

• Sedimentation

• Heat and pressure

• Cooling

• Erosion

Which of the following is NOT a major type of rock?

• Crystalline

• Metamorphic

• Sedimentary

• Igneous