Igneous Rocks and Volcanism Review

These flashcards cover key vocabulary and concepts related to igneous rocks and volcanism as discussed in the lecture.

Iwo Jima

Site where 6,821 American soldiers died during World War II.

Plate Tectonics

The theory explaining the structure of the Earth's crust and the movement of its plates.

Igneous Rocks

Rocks formed by the solidification of molten material (magma or lava).

Felsic Composition

Igneous rocks that are rich in lighter colored minerals, typically containing high silica content.

Mafic Composition

Igneous rocks that are rich in darker colored minerals, typically containing low silica content.

Explosive Eruption

A volcanic eruption characterized by the violent expulsion of magma and gases.

Effusive Eruption

A volcanic eruption characterized by the flow of lava without explosive activity.

Bowen’s Reaction Series

A sequence that illustrates the order in which minerals crystallize from cooling magma.

Continuous Series

Refers to the gradual change in composition of plagioclase from calcium-rich to sodium-rich over different temperature zones.

Discontinuous Series

Refers to the crystallization of different minerals at specific temperature ranges.

Magma Generation

The processes by which magma forms, including partial melting, decompression melting, and flux melting.

Fractional Crystallization

The process by which different minerals crystallize from magma at different temperatures.

Partial Melting

The process through which some minerals in solid rock melt while others remain solid, creating magma.

Crystal Size

Determined by the rate at which the magma cools; slower cooling leads to larger crystals.

Intrusive Igneous Rock

Igneous rocks formed from magma that cools slowly beneath the Earth's surface.

Extrusive Igneous Rock

Igneous rocks formed from lava that cools quickly on the Earth's surface.

Fine-Grained Texture

Indicates rapid cooling of magma, resulting in small crystals.

Coarse-Grained Texture

Indicates slow cooling of magma, results in larger crystals.

Pyroclastic Flow

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

Lahar

A destructive mudflow on the slopes of a volcano.

Tephra

Fragmental material produced by a volcanic eruption.

Volcanic Gas

Gases released into the atmosphere during an eruption, which can contribute to explosive activity.

Shield Volcano

A type of volcano characterized by low viscosity lava flows and a broad, gently sloping shape.

Composite Volcano

A steep-sided volcano formed from alternating layers of lava and ash.

Cinder Cone

A small, steep volcano formed from explosive eruptions that deposit tephra around the vent.

Basalt

A common mafic volcanic rock formed from the rapid cooling of lava.

Rhyolite

A common felsic volcanic rock with high silica content.

Andesite

An intermediate volcanic rock, often associated with convergent tectonic plate boundaries.

Volcanic Ash

Fine particles of rock and glass produced during explosive volcanic eruptions.

Columnar Jointing

A geological feature that develops in cooling lava flows characterized by hexagonal columns.

Viscosity of Magma

The measure of a fluid's resistance to flow; affects eruption style.

Mantle Plume

An upwelling of hot rock within the Earth's mantle that can lead to volcanic activity.

Volcanic Eruption

The process through which material from beneath the Earth's crust escapes to the surface.

Volcanic Products

Materials such as lava, ash, volcanic gases, and pyroclastic debris released during an eruption.

Dome Volcano

A volcano formed by the slow eruption of viscous lava, creating a dome-shaped structure.

Subduction Zone

An area where one tectonic plate moves under another, often creating volcanic activity.

Active Volcano

A volcano that has erupted in recent history or is expected to erupt again.

Dormant Volcano

A volcano that is not currently erupting but could potentially erupt in the future.

Extinct Volcano

A volcano that is not expected to erupt again.

Volcanic Hazards

Potential dangers that volcanic activities pose to humans and the environment.