Unit 4 - Earth Systems and Resources APES Vocab

Magma

Molten rock beneath Earth's surface.

Asthenosphere

The semi-fluid layer of the mantle on which tectonic plates move.

Lithosphere

The rigid outer layer of Earth, including the crust and upper mantle.

Fault

A fracture in Earth's crust where movement has occurred.

Divergent Boundary

A plate boundary where two plates move apart, creating new crust.

Convergent Boundary

A plate boundary where two plates collide, causing subduction or mountain building.

Transform Boundary

A plate boundary where plates slide past each other horizontally.

Subduction/Subduction Zone

Area where one tectonic plate sinks beneath another into the mantle.

Collision Zone

Area where two continental plates collide, forming mountains.

Hotspots

Areas of volcanic activity caused by plumes of magma rising through the mantle.

Island Arcs

Chains of volcanic islands formed along subduction zones.

Seafloor Spreading

The process of new oceanic crust forming at mid-ocean ridges and moving outward.

Rift Valleys

Deep valleys formed where tectonic plates diverge on land.

Mid-Oceanic Ridges

Underwater mountain chains formed by seafloor spreading.

Ring of Fire

The zone of frequent earthquakes and volcanoes around the Pacific Ocean.

Humus

Decayed organic matter in soil that improves fertility and water retention.

Parent Material

The original rock or sediment from which soil forms.

Topography

The shape and features of Earth's surface, influencing soil and water movement.

Topsoil

The nutrient-rich upper layer of soil where most plant roots grow.

Soil Degradation

The decline in soil quality due to erosion, compaction, or nutrient loss.

Soil Texture

The relative proportion of sand, silt, and clay in soil.

Porosity

The amount of pore space in soil that can hold air or water.

Permeability

The ability of soil to transmit water.

Water Holding Capacity

The ability of soil to retain water for plant use.

Solar Radiation

Energy emitted by the sun reaching Earth.

Insolation

The amount of solar radiation received by a specific area.

Latitude

The distance north or south of the equator, affecting climate and sunlight intensity.

Equinox

The time of year when day and night are equal in length.

Solstice

The time when the sun is at its highest or lowest point in the sky, marking seasonal change.

Convection cycles/current

Circular movement of fluids caused by heat rising and cool material sinking.

Hadley Cells

Atmospheric convection cells that move warm air from the equator to about 30° latitude.

Coriolis Effect

The deflection of moving air and water due to Earth's rotation.

Rainshadow effect

Dry conditions on the leeward side of a mountain caused by moisture loss on the windward side.

ENSO (El Niño Southern Oscillation)

Climate pattern involving changes in Pacific Ocean temperatures and wind patterns.

El Niño

Warming of Pacific waters causing weakened trade winds and global weather changes.

La Niña

Cooling of Pacific waters causing stronger trade winds and opposite weather effects of El Niño.

Upwelling

The rise of cold, nutrient-rich water to the ocean surface.

Thermohaline Circulation

Global ocean circulation driven by differences in temperature and salinity.

Watershed

The land area that drains into a particular river, lake, or ocean.

Riparian Buffer

Vegetated area along waterways that protects against erosion and filters pollutants.