Igneous Rocks Video

Flashcards covering key concepts related to igneous rocks, their formation, and the rock cycle.

Igneous rocks

Rocks that form from the cooling of magmas and lavas.

Sedimentary rocks

Rocks formed from sediments of various sizes and types.

Metamorphic rocks

Rocks that formed from any rock type undergoing changes due to heat and pressure.

Crystallization

The process where atoms and molecules lose thermal energy and combine to form minerals.

Lithification

The process of turning sediments into sedimentary rock through compaction and cementation.

Weathering

The process of breaking apart rocks into smaller pieces by natural forces.

Magma vs Lava

Magma is molten rock below the surface, lava is molten rock on the surface.

Decompression melting

Melting that occurs when pressure is released from a material, allowing it to liquefy.

Partial melting

When certain minerals in a rock melt at lower temperatures while others remain solid.

Geothermal gradient

The rate at which temperature increases with depth below the Earth's surface.

Bowen's Reaction Series

A concept that explains which minerals crystallize at which temperatures during magma cooling.

Mafic magma

Magmas derived from the melting of the mantle that are high in iron and magnesium.

Felsic magma

Magmas derived from the melting of continental crust that are low in density and silica-rich.

Porphyritic texture

A texture characterized by large crystals (phenocrysts) embedded in a finer-grained matrix.

Vesicular texture

A texture containing gas bubbles formed during the cooling of lava.

Phaneritic texture

A coarse-grained texture in which individual mineral crystals are visible.

Aphanitic texture

A fine-grained texture in which individual mineral crystals are too small to see.

Xenolith

A rock fragment that becomes enclosed in another rock while it's forming.

Batholith

A large, irregularly shaped pluton formed from solidified magma beneath the Earth's surface.

Dike

A vertical or non-horizontal intrusion of magma that cuts across existing rock layers.

Sill

A horizontal or nearly horizontal intrusion of magma between existing rock layers.

Pegmatite

A very coarse-grained igneous rock that forms from slow cooling and is often found in granitic environments.

Obsidian

A natural volcanic glass that has a glassy texture due to rapid cooling.

Pumice

A light, porous volcanic rock that has a vesicular texture.