GEOG 203: Planet Earth

Flashcards covering key concepts related to Earth's structure, rock types, tectonic processes, and geological cycles for GEOG 203.

Core

The innermost layer of the Earth, composed primarily of solid iron and molten iron, which accounts for 1/6 of the Earth's volume and 1/3 of its mass.

Mantle

The layer of the Earth between the crust and the core, making up about 80% of the Earth’s volume and potentially containing water in crystalline form.

Lithosphere

The rigid outer layer of the Earth, comprising the uppermost mantle and the crust, with an average thickness of about 70 km.

Asthenosphere

The semi-fluid layer upon which the lithosphere floats, allowing for plate movement.

Igneous Rocks

Rocks that form from the crystallization of magma or lava; they can be classified as intrusive or extrusive based on their cooling rate.

Sedimentary Rocks

Rocks that result from the compaction and cementation of sediments, which can include mineral grains, boulders, and other organic materials.

Metamorphic Rocks

Rocks that have been transformed due to extreme temperature and pressure, changing their mineral composition and texture.

Seafloor Spreading

The process by which new oceanic crust is created through upwelling magma at mid-ocean ridges.

Subduction

The process where denser oceanic crust sinks beneath less dense continental crust, leading to recycling of crustal material into the mantle.

Plate Boundaries

The edges where two tectonic plates meet, which can be classified as divergent, convergent, or transform boundaries.

Hydrologic Cycle

The continuous cycle of water movement in the Earth’s atmosphere and surface, including evaporation, condensation, precipitation, and runoff.

Tectonic Cycle

The process of creation, movement, and destruction of tectonic plates that shape the Earth's surface over geological time.

Rock Cycle

continuous process through which rocks are formed, broken down, and reformed by geological processes

Magnetic Reversals

Periods when the Earth's magnetic field changes direction, resulting in the north and south magnetic poles switching places.

Hot Spot

A volcanic region where magma rises through the Earth's crust, creating islands or volcanic activity independent of tectonic plate boundaries.

Crust

The outermost layer of the Earth, composed of solid rock, which is divided into continental and oceanic crust.