Apes ch 8 vocab

A horizon (topsoil)

Frequently the top layer of soil, characterized by mixing of organic material and mineral material

Acid rain (acid precipitation)

Precipitation high in sulfuric acid and nitric acid from reactions between sulfur dioxide and water vapor and nitrogen oxides and water vapor in the atmosphere

Asthenosphere

The layer of Earth located in the outer part of the mantle, composed of semi-molten rock.

B horizon

Frequently the second major soil horizon, composed primarily of mineral material with very little organic matter.

Base saturation

The proportion of soil bases to soil acids, expressed as a percentage

C horizon

The least-weathered soil horizon, which always occurs beneath the B horizon and is similar to the parent material.

Cation exchange capacity (CEC)

The ability of a particular soil to absorb and release cations

Chemical weathering

The breakdown of rocks and minerals by chemical reactions, the dissolving of chemical elements from rocks, or both

Convergent plate boundary

An area where plates move toward one another and collide

Core

In reference to Earth, the innermost layer.

Crust

In geology, the chemically distinct outermost layer of the lithosphere.

Crustal abundance

The average concentration of an element in Earth's crust

Deposition

The accumulation or depositing of eroded material such as sediment, rock fragments, or soil

Divergent plate boundary

An area beneath the ocean where tectonic plates move away from each other

E horizon

The zone of leaching that forms under the O horizon or, less often, the A horizon.

Earthquake

The sudden movement of Earth's crust caused by a release of potential energy along a geologic fault and usually causing a vibration or trembling at Earth's surface.

Epicenter

The exact point on the surface of Earth directly above the location where rock ruptures during an earthquake.

Erosion

The physical removal of rock fragments from a landscape or ecosystem

Extrusive igneous rock

Rock that forms when magma cools above the surface of Earth

Fault

A fracture in rock caused by a movement of Earth's crust

Fault zone

A large expanse of rock where a fault has occurred

Fracture

In geology, a crack that occurs in rock as it cools

Hot spot

In geology, a place where molten material from Earth's mantle reaches the lithosphere.

Igneous rock

Rock formed directly from magma

Intrusive igneous rock

Igneous rock that forms when magma rises up and cools in a place underground

Lithosphere

The outermost layer of Earth, including the mantle and crust.

Magma

Molten rock

Mantle

The layer of the earth between the crust and the core

Metal

An element with properties that allows it to conduct electricity and heat energy, and perform other important functions.

Metamorphic rock

Rock that forms when sedimentary rock, igneous rock, or other metamorphic rock is subjected to high temperature and pressure.

Mineral

A solid chemical substance with a uniform, often crystalline, structure that forms under specific temperatures and pressures.

Mining spoils (tailings)

Unwanted waste material created during mining

Mountaintop removal

A mining technique in which the entire top of a mountain is removed with explosives

O horizon

The organic horizon at the surface of many soils, composed of organic detritus in various stages of decomposition

Open-pit mining

A mining technique that uses a large pit or hole in the ground, visible from the surface of Earth.

Ore

A concentrated accumulation of minerals from which economically valuable materials can be extracted

Parent material

Rock underlying soil; the material from which the inorganic components of a soil are derived

Physical weathering

The mechanical breakdown of rocks and minerals

Placer mining

A mining technique in which metals and precious stones are sought in river sediments

Plate tectonics

The theory that the lithosphere of Earth is divided into plates, most of which are in constant motion.

Reserve

In resource management, the known quantity of a resource that can be economically recovered

Richter scale

A scale that measures the largest ground movement that occurs during an earthquake

Rock cycle

The continuous formation and destruction of rock on and below the surface of Earth.

Seafloor spreading

The formation of new ocean crust as a result of magma pushing upward and outward from Earth's mantle to the surface.

Sedimentary rock

Rock that forms when sediments such as muds, sands, or gravels are compressed by overlying sediments

Seismic activity

The frequency and intensity of earthquakes

Soil

A mix of geologic and organic components that forms a dynamic membrane covering much of Earth's surface.

Soil degradation

The loss of some or all of a soil's ability to support plant growth

Strip mining

The removal of strips of soil and rock to expose ore

Subduction

The process of one crustal plate passing under another

Subsurface mining

Mining techniques used when the desired resource is more than 100 m (328 feet) below the surface of Earth.

Tectonic cycle

The cycle of processes that build up and break down the lithosphere

Texture

The property of soil determined by relative proportions of sand, silt, and clay

Topography

The arrangement of the natural and artificial physical features of an area.

Transform fault boundary

An area where tectonic plates move sideways past each other

Volcano

A vent in the surface of Earth that emits ash, gases, or molten lava.