Volcanic and Geological Concepts

Intrusive & Extrusive Igneous Rocks

• Intrusive rocks form from lava cooling quickly on the surface, while extrusive rocks form from magma cooling slowly beneath the surface.

• Intrusive rocks form from magma cooling slowly beneath the surface, while extrusive rocks form from lava cooling quickly on the surface.

• Intrusive rocks are formed from sedimentary processes, while extrusive rocks are formed from metamorphic processes.

• Intrusive rocks are always found on the Earth's surface, while extrusive rocks are found deep underground.

Lahars

• A type of volcanic eruption

• A destructive volcanic mudflow on the slopes of a volcano.

• A type of lava flow

• A volcanic gas emission

Subduction Zone

• A region where one tectonic plate moves under another, sinking into the mantle as the plates converge.

• A place where tectonic plates slide past each other horizontally.

• An area where tectonic plates are moving apart, creating new crust.

• A zone where tectonic plates collide and form mountains.

Tephra

• Fragments of volcanic rock and ash ejected during an eruption.

• A type of sedimentary rock formed from compressed sand.

• A volcanic gas that contributes to acid rain.

• A mineral found only in igneous rocks.

Pyroclastic Flows

• A slow-moving stream of lava that flows down the side of a volcano.

• A fast-moving current of hot gas and volcanic matter that moves away from a volcano at high speed.

• A type of volcanic eruption that produces only ash and gas.

• A solid mass of rock that forms inside a volcano.

Stratovolcanoes

• A type of volcano characterized by a steep profile and periodic explosive eruptions.

• A type of volcano that is primarily formed by lava flows and has a broad, gently sloping profile.

• A type of volcano that erupts only once and then becomes dormant.

• A type of volcano that is formed by the accumulation of ash and small fragments of rock.

Magma

• Molten rock beneath the Earth's surface, which can form lava when it erupts.

• A type of sedimentary rock found on the Earth's surface.

• A solid form of rock that is found in the Earth's crust.

• A gas released during volcanic eruptions.

Shield Volcanoes

• A type of volcano with a broad, domed shape and gentle slopes, formed by the eruption of low-viscosity lava.

• A type of volcano that erupts explosively and has steep slopes, formed by the accumulation of thick lava flows.

• A type of volcano that is primarily formed by the accumulation of ash and tephra, resulting in a conical shape.

• A type of volcano that is characterized by a series of fissure eruptions, leading to a flat landscape.

Hot Spot

• A location where magma from deep within the mantle melts through the crust, often forming a chain of volcanoes.

• A region where tectonic plates meet and cause earthquakes.

• An area with high temperatures due to geothermal activity.

• A place where ocean currents converge and create storms.