Igneous Rocks and the Rock Cycle

What material is expelled during a volcanic eruption?

Which type of igneous rock is characterized by small crystals?

What is formed when igneous rocks are eroded and their sediments are deposited?

What describes the transformation of rocks from one type to another over millions of years?

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

Igneous Rocks

Formed by volcanic activity
"Ignis" means "fire"
Can be glassy or crystalline
Molten rock material inside Earth is called magma
Magma expelled through vent during volcanic eruption
Molten material called lava
Lava cools and hardens to form igneous rocks
Speed of cooling determines type of igneous rock

Extrusive Igneous Rocks

Formed when lava cools rapidly on Earth’s surface
Have small crystals
Examples include basalt and pumice
Deccan Plateau is largely made of basalt

Intrusive Igneous Rocks

Formed when magma cools slowly before reaching the surface
Have large crystals
Are coarse-grained and hard
Example is granite
Igneous rocks contain holes from gas bubbles

The Rock Cycle

Describes how rocks transform over millions of years
Igneous rocks can be eroded, forming sediments
Sediments deposit on land or in seabeds
Sediments form sedimentary rocks
Over time, sedimentary rocks can be altered by high heat and pressure, forming metamorphic rocks
Metamorphic rocks can melt into magma, completing the cycle

Explore the fascinating world of igneous rocks, formed through volcanic activity. This quiz covers the differences between extrusive and intrusive igneous rocks, their formation processes, and the overall rock cycle. Test your knowledge of magma, lava, and the characteristics of different rock types.