Keywords 3.3

Chile burns

Archipelago

A group of islands

Basalt

Dark, dense volcanic rock that forms from fast-cooling lava; common at ocean floors.

Convection current

Flowing heat in the mantle that moves tectonic plates.

Divergence

When two tectonic plates move away from each other.

Earthquake

Sudden shaking of the ground caused by movement in Earth's crust.

Effusive eruption

A gentle volcanic eruption with runny lava that flows easily.

Explosive eruption

A violent volcanic eruption with thick lava, ash, and gas.

Granite

Light-colored rock that forms slowly underground; found in continental crust.

Hotspot

A weak spot in Earth's crust where magma rises from deep in the mantle.

Igneous rock

Rock formed from cooled lava or magma

Lava

Molten rock that flows out of a volcano onto Earth's surface.

Main vent

The main opening through which magma exits during a volcanic eruption.

Magma

Molten rock beneath the Earth's surface.

Mantle

The thick layer of hot rock between Earth's crust and core.

Mantle plume

A rising column of hot magma from deep in the mantle, often causing hotspots.

Mid-ocean ridge

An underwater mountain range formed by diverging oceanic plates.

Pyroclastic flow

A fast, deadly mix of hot gas, ash, and rock that rushes down a volcano.

Shield volcano

A wide, gently sloping volcano formed by runny lava.

Strato volcano

A tall, steep volcano made from layers of lava and ash; known for explosive eruptions.

Subduction

When one tectonic plate slides under another and sinks into the mantle.

Tectonic plates

A large, moving piece of Earth's crust and upper mantle.