Geology Lecture: Minerals, Igneous, and Metamorphic Rocks

Vocabulary flashcards covering key terms and concepts regarding mineral classification, Bowen's reaction series, igneous rock textures, and metamorphic processes from Chapter 1 to Chapter 8.

Silicates

The most dominant mineral group in the Earth's crust, characterized by chemical formulas containing silicon and oxygen.

Bowen's reaction series

A arrangement of rock-forming silicate minerals showing the specific order and temperature conditions under which minerals crystallize from cooling magma or melt from solid rock.

Calcite

A non-silicate carbonate mineral composed of calcium, carbon, and oxygen, which forms limestone and serves as the structural material for coral reefs and shells.

Acid mine drainage

An environmental problem caused when sulfide minerals exposed to oxygen react to form sulfuric acid, dissolving and mobilizing toxic heavy metals into liquid solution.

Gypsum

An evaporite sulfate mineral composed of calcium, sulfur, and oxygen that is mined to make wallboard.

Apatite

A phosphate mineral composed of calcium phosphate found in human teeth and extracted to supply essential phosphorus for agricultural fertilizers.

Rhodochrosite

The official state mineral of Colorado, composed of manganese carbonate, which gives it a bright rose-red color.

Alma King

The largest rhodochrosite crystal ever discovered on Earth, originating from a mine near Alma in South Park, Colorado.

Geothermal gradient

A plot or measurement showing the rate at which temperature increases with increasing depth below the Earth's surface.

Phaneritic texture

An intrusive igneous rock texture characterized by visible, coarse-grained interlocking mineral crystals formed by slow cooling beneath the surface.

Aphanitic texture

An extrusive igneous rock texture consisting of fine, microscopic mineral crystals resulting from rapid cooling at or near the surface.

Obsidian

An extrusive igneous rock classified as volcanic glass, formed when magma cools so rapidly that mineral crystals cannot grow.

Porphyritic texture

An igneous rock texture featuring large visible phenocrysts surrounded by a groundmass of microscopic crystals, indicating a two-stage cooling history.

Pyroclastic texture

An extrusive igneous rock texture characterized by broken, fragmental volcanic material produced by violent volcanic eruptions.

Peridotite

An intrusive phaneritic ultramafic rock that comprises the Earth's mantle and represents the most volumetrically abundant rock on Earth.

Protolith

The original parent rock that undergoes physical or chemical changes under elevated heat and pressure to become a metamorphic rock.

Lithostatic pressure

Uniform pressure exerted equally in all directions on a deeply buried rock by the weight of overlying rocks.

Differential stress

Non-uniform stress applied greater in one direction than in others, which creates a foliated texture in metamorphic rocks.

Foliation

A metamorphic rock texture defined by the parallel alignment of mineral grains under differential stress.

Gneiss

A high-grade foliated metamorphic rock displaying distinct alternating bands of dark and light minerals.

Migmatite

A hybrid rock that is part metamorphic and part igneous, formed when the light-colored, high-silica bands of a gneiss melt into granite squiggles.