UNIT 3 GEOLOGY VOCABULARY FLASHCARDS THESE KEY VOCABULARY WORDS AND PHRASES APPEAR ON THE UNIT 3 CBA
A map that shows Earth s Topographic Map surface topography, which is Earth s shape and features
Contour Lines A line on a topographic map that connects points of equal elevation
Contour interval The elevation difference between contour lines
Elevation The height above sea level of any point on Earth s surface
Cross Section The profile (side) view that shows a vertical slice through rocks below the surface.
Slope A measure of the steepness of the land
Relief The difference in elevation between the highest and lowest point in an area.
Weathering The process by which a rock is worn down and broken apart.
Chemical Weathering Weathering due to chemical breakdown of rocks, such as reacting to acid rain or rusting
Physical (Mechanical) Weathering The physical breaking or rock due to physical processes, such as water, ice, wind, plant roots, or abrasion.
Erosion The process of sediment moving from one place to another due to gravity, water, or wind.
Deposition The process by which eroded materials are dropped off, or deposited, in a new location.
Landform A natural structure on Earth s surface, such as a mountain, rift valley, or a trench.
The part of a rock formation that appears above the surface of the surrounding land Outcropping
Delta A landform formed at the mouth of a river from the deposition of eroded sediments
Canyon A deep valley with very steep sides - often carved from the Earth by river erosion.
Sand Dune A large hill or ridge made of sand that is shaped and reshaped by wind.
Sediments Small pieces of minerals, rocks, sand, organic material, and/or shells.
Sedimentary Rocks Rocks that are formed under a body of water when sediments are compacted and cemented together.
Metamorphic Rocks A type of rock formed from intense heat and pressure when an existing rock is morphed or changed into a new rock within Earth s interior.
Igneous Rock A type of rock formed when lava cools and hardens
The gradual movement of the continents across the earth's surface over a long period of time due to convection currents in the mantle Continental Drift
Continental Crust thick part of the earth's crust that forms the large landmasses. It is generally older and more complex than the oceanic crust.
Oceanic Crust Thin part of the earth's crust that underlies the ocean basins. It is geologically young compared with the continental crust and consists of basaltic rock overlain by sediments.
Convergent Plate Boundary The boundary between two colliding tectonic plates.
Transform Plate Boundary The boundary between two tectonic plates that sliding past each other (neither colliding nor pulling apart)
Divergent Plate Boundary The boundary between two tectonic plates that are pulling apart.
The process of denser oceanic crust colliding with either oceanic crust or continental crust and plunging downward into the mantle. Subduction
Shear stress is experienced at transform boundaries where two plates are sliding past each other. Shearing
Compression Compressive stress happens at convergent plate boundaries where two plates move toward each other.
Island Arc A curved chain of volcanic islands located at plate boundaries along subduction zones. An example is the Aleutian Islands.
Trench A long, deep depression in the ocean floor along a subduction zone at a plate boundary
Mid-Ocean Ridge A long underwater ridge system that occurs where two plates are diverging in the middle of an ocean basin resulting in the upwelling of magma associated with seafloor spreading. (An example is the Mid- Atlantic Ridge)
A valley with steep sides; formed by a rift, or large split, occurring along divergent plate boundaries. Rift Valley
The landform created from two continental crustal plates colliding Folded Mountain
Volcanic Mountain An opening, or rupture, in the surface or crust of the Earth which allows hot lava, volcanic ash and gases to escape from the magma chamber below the surface. On Earth, volcanoes are generally found where tectonic plates are diverging or converging