APES Ch 8 Vocab

the innermost layer of the Earth.
the layer of the Earth above the core, containing magma.
Molten rock.
the layer of the Earth located in the outer part of the mantle, composed of semi-molten rock.
the outermost layer of Earth, including the mantle and crust.
the chemically distinct outermost layer of the Lithosphere.
a place where molten material from the Earth's mantle reaches the Lithosphere.
plate tectonics
the theory that the Lithosphere of Earth is divided into plates, most of which are constantly in motion.
tectonic cycles
the cycle of processes that build up and break down the Lithosphere.
the process of one crustal plate passing under another.
a vent in the surface of the Earth that emits ash, gases, or molten lava.
divergent plate boundaries
an area beneath the ocean where tectonic plates move away from each other.
seafloor spreading
the formation of new ocean crust as a result of magma pushing upward and outward from Earth's mantle to the surface.
convergent plate boundaries
an area where plates move towards one another and collide.
transform fault boundary
an area where tectonic plates move sideways past each other.
a fracture in rock caused by the movement of earth's crust.
fault zones
a large expanse of rock where a fault has occurred.
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.
seismic activity
the frequency and intensity of earthquakes.
the exact point on the surface of the Earth directly above the location where rock ruptures during an earthquake.
Richter scales
scales used to measure the magnitude of an earthquake.
Rock cycle
the continuous formation and destruction of rock on and below the surface of the Earth.
a solid chemical substance with a uniform, often crystalline, structure that forms under specific temperatures and pressures.
igneous rocks
formed through the cooling and solidification of magma.
Igneous rock that forms when magma rises up and cools in place underground.
Igneous rock that forms when magma cools above the surface of the Earth.
a crack that occurs in rock as it cools.
sedimentary rocks
rock that is formed when layers of sediments, such as sand, mud, or gravels, is compressed under other layers of sediment.
metamorphic rocks
rock that forms when igneous, sedimentary, or other metamorphic rock is subjected to high temperature and pressure.
physical weathering
the mechanical breakdown of rocks and minerals.
chemical weathering
the breakdown of rocks and minerals from chemical reactions, the dissolving of chemical elements from rocks, or both.
acid rain
sulfuric acid + rainwater
the physical removal of rock fragments from a landscape or ecosystem.
the accumulation or depositing of eroded minerals, such as sediment, rock fragments, or soil.
a mix of geologic and organic components that forms a dynamic membrane covering much of Earth's surface.
parent material
rock underlying soil; the material from which the inorganic components of soil are derived.
basically the layers of soil.
O horizon
undecomposed organic debris, decomposed organic material, and humus.
A horizon
a leached mineral horizon with a high proportion of organic matter. (topsoil).
same thing as A Horizon.
E horizon
A light colored layer representing an area of maximum leaching.
B horizon
Maximum zone of accumulation of weathering products such as silicate, clay, iron, aluminum, humus, carbonates, gypsum, or silica.
C horizon
Relatively unaltered unconsolidated parent material.
the property of soil determined by proportions of sand, silt, and clay.
Cation exchange capacity
the ability of a particular soil to absorb and release cations.
soil bases
Base-richness in ecology is the level in water or soil of chemical bases, such as calcium or magnesium ions. Many organisms are restricted to base-rich environments. Chemical bases are alkalis, and so base-rich environments are neutral or alkaline.
soil acids
Soil pH or soil reaction is an indication of the acidity or alkalinity of soil and is measured in pH units. Soil pH is defined as the negative logarithm of the hydrogen ion concentration. The pH scale goes from 0 to 14 with pH 7 as the neutral point.
base saturation
the proportion of soil bases to soil acids, expressed as a percentage.
soil degradation
the loss of some or all of a soil's ability to sustain plant growth.
crustal abundance
the average concentration of an element in the crust of the Earth.
a concentrated accumulation of minerals from which economically valuable materials can be extracted.
an element that can conduct electricity and heat energy.
resource that can be economically recovered.
strip mining
the removal of strips of soil and rock to remove ore.
mining spoils (tailings)
unwanted waste material
open-pit mining
uses a large pit or hole in the ground.
mountaintop removal
they blow off the top of the mountain top to get to the inside.
placer mining
mining of river sediments,
subsurface mining
mining techniques when the desired resource is more than 100 m below surface of Earth.