GEOL 101 Exam 1 Review

Big Bang Theory

Proposes that all matter and energy in the Universe originated from a single infinitesimally small point.

Stellar Evolution

Describes the life cycle of stars, including the fusion of elements, supernovas, and the formation of heavier elements.

Nebular Theory

Explains the formation of the solar system from a rotating mass of cosmic dust and gas, leading to planet formation.

Differentiation

Process where denser materials sink to the core of a planet, creating layers like the core, mantle, and crust.

Mineral Criteria

Defines a mineral as naturally occurring, formed by geologic processes, inorganic, crystalline solid, and with a definite chemical composition.

Crystal Formation

Minerals are composed of elements bound by chemical bonds, forming crystals with specific atomic arrangements and properties.

Silicate Minerals

Most common rock-forming minerals on Earth, comprising the majority of the crust and mantle, with various structures like isolated tetrahedra or frameworks.

Igneous Rocks

Formed from the cooling and solidification of magma or lava, with different textures (crystalline or cemented) based on the cooling environment.

Volcanic Eruptions

Vary in types like effusive (low viscosity) or explosive (high viscosity), leading to different volcano shapes such as shield, cinder cone, or stratovolcano.

Calderas

Enormous volcanic depressions formed when a magma chamber empties, causing the collapse of the volcano into the void, creating a large circular depression.

Rhyolitic lava

Viscous lava that rarely flows, forming lava domes when it plugs the vent.

Pahoehoe

Basalt lava with a ropy texture, formed from extremely hot basalt cooling and flowing.

A’a’

Basalt lava with a jagged, sharp texture, formed from solidified Pahoehoe lava.

Columnar jointing

Fracturing that creates hexagonal columns in basalt when it cools.

Pillow basalt

Basaltic lava cooling quickly in water, forming glass-encrusted blobs due to pressure.

Pyroclastic

Mix of rock fragments, pumice, and volcanic ash.

Tuff

Volcanic ash and fragmented pumice cemented together, forming glass shards.

Obsidian

Volcanic glass formed from rapidly cooled lava.

Lahar

Rapidly flowing slurry of ash-rich debris becoming very wet.

Debris flow

Wetted debris moving downhill like wet concrete.

Pyroclastic flow

Avalanche of hot ash, gas, and debris, known for the destruction of Pompeii.

Mafic lava

Low silica content, low viscosity, and low volatiles, characteristic of basalt rocks.

Felsic lava

High silica content, high viscosity, and high volatiles, characteristic of andesite and rhyolite.

Mid-ocean ridges

Locations where MOR-generated oceanic crust forms from decompression melting of mantle rock.

Convergent boundaries

Locations where most stratovolcanoes form due to flux melting in the lithosphere.

Continental rift zones

Areas where fractional crystallization and assimilation or heat transfer cause melting of continental crust.

Hot spots

Locations where decompression melting in the asthenosphere and lithosphere creates large volumes of magma.

Iceland

Known for mantle plume hot spots coinciding with mid-ocean ridges.

Yellowstone

Known for mantle plumes cutting through continental crust, creating large volumes of felsic magma.