Unit 2 vocab Flashcards
Pangaea
A name given to a supercontinent that broke apart approximately 200 million years ago
Continental Drift
the gradual movement of the continents across the earth’s surface through
Mid-ocean ridges
a long, seismically active submarine ridge system situated in the middle of an ocean basin and marking the site of the upwelling of magma associated with seafloor spreading. An example is the Mid-Atlantic Ridge.
Ocean trenches
Ocean trenches are long, narrow depressions on the seafloor. These chasms are the deepest parts of the ocean
Seafloor spreading
the formation of new areas of oceanic crust, which occurs through the upwelling of magma at midocean ridges and its subsequent outward movement on either side.
Magma
Lava
hot fluid or semifluid material below or within the earth’s crust from which lava and other igneous rock is formed on cooling.
Plate tectonics
a theory explaining the structure of the earth’s crust and many associated phenomena as resulting from the interaction of rigid lithospheric plates which move slowly over the underlying mantle.
Convergent boundaries
A tectonic boundary where two plates are moving toward each other. If the two plates are of equal density, they usually push up against each other
Divergent boundaries
A tectonic boundary where two plates are moving away from each other and new crust is forming from magma that rises to the Earth’s surface between the two
Transform boundaries
Transform Plate Boundaries are locations where two plates slide past one another
Subduction
the sideways and downward movement of the edge of a plate of the earth’s crust into the mantle beneath another plate.
Volcano
a mountain or hill, typically conical, having a crater or vent through which lava, rock fragments, hot vapor, and gas are being or have been erupted from the earth’s crust.
Fault
(of a rock formation) be broken by a fault or faults.
Volcanic arc
A volcanic arc is a belt of volcanoes formed above a subducting oceanic tectonic plate, with the belt arranged in an arc shape as seen from above.
Earthquake
a sudden and violent shaking of the ground, sometimes causing great destruction, as a result of movements within the earth’s crust or volcanic action.
Fault zone
A fault zone is a cluster of parallel faults. However, the term is also used for the zone of crushed rock along a single fault.
Landslide
the sliding down of a mass of earth or rock from a mountain or cliff.
Tsunami
a long high sea wave caused by an earthquake, submarine landslide, or other disturbance
Impact craters
a crater on a planet or moon caused by the impact of a meteorite or other object, typically circular with a raised rim.
Weathering
the process of wearing or being worn by long exposure to the atmosphere.
Erosion
the process of eroding or being eroded by wind, water, or other natural agents.
“the problem of soil erosion”
Deposition
Deposition is the laying down of sediment carried by wind, flowing water, the sea or ice.
Glacier
A glacier is a large, perennial accumulation of crystalline ice, snow, rock, sediment, and often liquid water that originates on land and moves down slope under the influence of its own weight and gravity.
Rock
a natural substance composed of solid crystals of different minerals that have been fused together into a solid lump
Mineral
A mineral is a naturally occurring inorganic element or compound having an orderly internal structure and characteristic chemical composition, crystal form, and physical properties.
Crystallization
Crystallization can be defined as the solidification of a liquid substance into a highly structured solid whose atoms or molecules are placed in a well-defined three-dimensional crystal lattice
Extrusive rock
Extrusive rock refers to the mode of igneous volcanic rock formation in which hot magma from inside the Earth flows out (extrudes) onto the surface as lava or explodes violently into the atmosphere to fall back as pyroclastics or tuff.
Intrusive rock
igneous rock formed from magma forced into older rocks at depths within the Earth’s crust, which then slowly solidifies below the Earth’s surface, though it may later be exposed by erosion
Lithification
lithification, complex process whereby freshly deposited loose grains of sediment are converted into rock. Lithification may occur at the time a sediment is deposited or later.
Compaction
happens when sediments are deeply buried, placing them under pressure because of the weight of overlying layers. This squashes the grains together more tightly.
Cementation
Cementation is the precipitation of a binding material around grains, thereby filling the pores of a sediment.
Rock cycle
The rock cycle is a web of processes that outlines how each of the three major rock types—igneous, metamorphic, and sedimentary—form and break down based on the different applications of heat and pressure over time. For example, sedimentary rock shale becomes slate when heat and pressure are added.
