Understanding Igneous Rock Formation

What is the primary process through which igneous rocks are formed?

• Sedimentation

• Cooling and solidification of magma or lava

• Metamorphism

• Erosion

Which of the following is an example of an intrusive igneous rock?

• Basalt

• Granite

• Pumice

• Obsidian

What is the main difference between intrusive and extrusive igneous rocks?

• Intrusive rocks form on the Earth's surface, while extrusive rocks form below the surface.

• Intrusive rocks have larger crystals due to slower cooling, while extrusive rocks have smaller crystals due to rapid cooling.

• Intrusive rocks are always darker in color than extrusive rocks.

• Intrusive rocks are formed from lava, while extrusive rocks are formed from magma.

Which of the following is a characteristic of basalt?

• Coarse-grained texture

• Light color

• Fine-grained texture

• High silica content

What is the term used to describe the molten rock beneath the Earth's surface?

• Lava

• Magma

• Sediment

• Ash

Which of the following igneous rocks is known for its glassy texture?

• Granite

• Diorite

• Obsidian

• Gabbro

What is the primary mineral composition of granite?

• Quartz, feldspar, and mica

• Olivine and pyroxene

• Calcite and dolomite

• Halite and gypsum

Which of the following processes can lead to the formation of igneous rocks?

• Melting and cooling

• Weathering and erosion

• Compaction and cementation

• Evaporation and precipitation

What type of igneous rock is formed from lava that cools quickly on the Earth's surface?

• Intrusive

• Extrusive

• Metamorphic

• Sedimentary

Which of the following is a common use for pumice, an extrusive igneous rock?

• Building countertops

• Making jewelry

• Polishing and cleaning

• Road construction