Physical & Chemical Properties of Magmas

These flashcards cover key vocabulary and concepts related to the physical and chemical properties of magmas based on the provided lecture notes.

Magmas

Molten rock that originates beneath the Earth's surface and can crystallize to form igneous rock.

Temperature (T)

A measure of the average kinetic energy of the particles in a substance, important in defining the state of magma.

Lithostatic pressure

The pressure exerted by rocks above a certain point within the Earth's crust.

Mafic magmas

Igneous magmas containing a high percentage of magnesium and iron, generally hotter than felsic magmas.

Felsic magmas

Igneous magmas rich in silica, aluminum, and light minerals, typically cooler in temperature than mafic magmas.

Viscosity

A measure of a fluid's resistance to flow; higher viscosity indicates a thicker consistency.

Polymerization of silicon tetrahedra

The process by which silicon tetrahedra link together, affecting the viscosity of silicate liquids.

Stoke's Law

A mathematical equation that describes the settling velocity of particles in a fluid, influenced by factors such as viscosity and density.

Solubility of Volatiles

The capacity of magma to dissolve volatile components such as water or carbon dioxide, which affects melting and crystallization.

Crystallization

The process by which a liquid solidifies into a crystal structure, often occurring in cooling magma.

Explosive eruptions

Volcanic eruptions characterized by the violent release of gas and magma, often triggered by high volatile content.

Anhydrous conditions

State in which there is no water present, affecting melting points and crystallization behavior of magmas.

Hydrous conditions

State in which water is present, lowering the melting point of certain rocks and influencing crystallization order.

Eruptive Style

The manner in which a volcano erupts, influenced by the magma's viscosity, gas content, and temperature.

Density of Magma

Mass per unit volume of magma, affected by composition, temperature, and pressure.

Temperature range for magmas

Typically between 650 to 1200°C, but can reach up to approximately 1600°C.

Crystallization rate

The speed at which crystals form from molten material, often dependent on temperature and composition.

What is Bowen's Reaction Series?

Bowen's Reaction Series is a concept in geology that describes the sequence of minerals that crystallize from a cooling magma.

What are the two branches of Bowen's Reaction Series?

Bowen's Reaction Series consists of the discontinuous and continuous branches, each representing different mineral crystallization patterns.

What type of minerals crystallize first in Bowen's Reaction Series?

The minerals that crystallize first in Bowen's Reaction Series are typically silicate minerals like olivine and pyroxene.