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PLATE TECTONICS
SLHS PLATE TECTONICS
| Question | Answer |
|---|---|
| theory proposed by Alfred Wegener that states that the continents were once joined as a super continent | Continental Drift |
| large, ancient landmass that was composed of all the continents joined together | Pangea |
| Hess's theory that new seafloor is formed when magma is forced upward toward the surface at a mid-ocean ridge | Seafloor Spreading |
| theory that Earth's crust and upper mantle are broken into plates that float and move around on a plasticlike layer of the mantle | Plate Tectonics |
| a large section of Earth's oceanic or continental crust and rigid upper mantle that moves around on the athenosphere | Plate |
| Large pieces of earth's crust | plates |
| Theory based on evidence that plates are moving slowly and constantly. | Theory of Plate Tectonics |
| Supercontinent | Pangea |
| Cracks between the plates | plate boundaries |
| force that acts on rock to change its shape or volume | stress |
| stress that pushes a mass of rock in two opposite directions | shearing |
| stress that squeezes rock until it folds or breaks | compression |
| stress force that pulls on the crust, stretching rock to become thinner | tension |
| shaking and trembling that results from the movement of rock beneath Earth's surface | earthquake |
| break in the Earth's crust where slabs of crust pass by each other | fault |
| Shearing creates this type of fault | slip-strike |
| Compression produces this type of fault | reverse |
| Tension forces in Earth's crust produce this type of fault | normal |
| Half the fault that lies above the fault | hanging wall |
| Half the fault that lies below the fault | footwall |
| bends in the rock | folds |
| large area of flat land elevated high above sea level | plateau |
| point beneath surface where rock is under stress and breaks | focus |
| point on surface directly above the focus | epicenter |
| first waves (compressional similar to a slinky) | p waves |
| secondary waves (move perpendicular to direction of movement) | s waves |
| move slower, but produce severe ground movements (making the ground roll like a water wave) | surface waves |
| Rates earthquakes according to intensity | Mercalli scale |
| a rating of the size of seismic waves measured by a seismograph | Richter scale |
| Scale used today by geologists | Moment Magnitude Scale |
| the theory that continents can drift apart from one another and have done so in the past | continental drift |
| the process by which new oceanic lithosphere is created at mid-ocean ridges as older materials are pulled away from the ridge | sea-floor spreading |
| the theory that the Earth's lithosphere is divided into tectonic plates that move around on top of the asthenosphere | plate tectonics |
| the boundary between two colliding tectonic plates | convergent boundary |
| the region where an oceanic plate sinks down into the asthenosphere at a convergent boundary, usually between continental and oceanic plates | subduction zone |
| the boundary between two tectonic plates that are moving away from each other | divergent boundary |
| the boundary between two tectonic plates that are sliding past each other horizontally | transform boundary |
| a break in the Earth's crust along which two blocks of the crust slide relative to one another | fault |
| the bending of rock layers due to stress in the Earth's crust | folding |
| the type of stress that occurs when an object is squeezed | compression |
| the type of stress that occurs when forces act to stretch an object | tension |
| the amount of force per unit area that is put on a given material | stress |
| a layer of hot rock | mantle |
| the part of the mantle that is made of soft rock that bends like plastic | asthenosphere |
| a dense ball of solid metal | inner core |
| the transfer of energy through empty space | radiation |
| heat transfer within a fluid | convection currents |
| the continents were once joined together in a single landmass | continental drift |
| the name of the supercontinent that existed millions of years ago | Pangaea |
| any trace of an ancient organism that has been preserved in rock | fossil |
| are found in all of Earth's oceans | mid-ocean ridges |
| technology used by scientists used in the mid-1900s to map the mid-ocean ridge | sonar |
| the process by which the ocean floor sinks beneath a deep-ocean trench and back into the mantle | subduction |
| the geological theory that states that pieces of Earth's lithosphere are in constant, slow motion | plate tectonics |
| forms at a divergent plate boundary | rift valley |
| molten material rises from the mantle and erupts along mid-ocean ridges | sea-floor spreading |
| produced by a collision between two pieces of continental crust at a converging boundary | mountain range |
| when you touch a hot pot or pan and energy moves from the pot to your hand | heat transfer |
| a place where two plates slip past each other, moving in opposite directions | transform boundary |
| Wegener's hypothesis taht all continents were once connected in a single large landmass that broke apart about 200 million years ago and drifted slowly to their current positions | Continental Drift |
| large, ancient landmass that was composed of all the continents joined together | Pangea |
| Hess's theory that new seafloor is formed when magma is forced upward toward the surface at a mid-ocean ridge | Seafloor Spreading |
| theory that Earth's crust and upper mantle are broken into plates that float and move around on a plasticlike layer of the mantle | Plate Tectonics |
| a large section of Earth's oceanic or continental crust and rigid upper mantle that moves around on the athenosphere | Plate |
| plasticlike layer of Earth on which the lithospheric plates float and move around | Asthenosphere |
| rigid layer of earth about 100 km thick made of the crust and a part of upper mantle | Lithosphere |
| current in Earth's mantle that transfers heat in Earth's interior and is the driving force for plate tectonics | Convection Current |
| vibrations produced when rocks break along a fault | Earthquake |
| seismic wave that moves rock particles back and forth in the same direction that the wave travels | Primary Waves |
| seismic wave that moves rock particles at right angles to the direction of the wave | Secondary Waves |
| seismic wave that moves rock particles up and down in a backward rolling motion and side to side in a swaying motion | Surface waves |
| point on earth's surface directly above an earthquake's focus | Epicenter |
| instrument used to register earthquake waves and record the time that each arrived | seismograph |
| opening in earth's surface that erupts sulfurous gases, ash, and lava, can form at earth's plate boundaries, where plates move apart or together, and at hot spots | volcano |
| opening where magma is forced up and flows out onto earth's surface as lava forming a volcano | vent |
| steep-walled depression around a volcano's vent | crater |
| the result of an unusually hot area at the boundary between earth's mantle and core that forms volcanoes when melted rock si forced upward and breaks through the crust | hot spot |
| broad, gently sloping volcano formed by quiet eruptions of basaltic lava | shield volcano |
| steep-sided, loosely packed volcano formed when tephra falls to the ground | cinder cone volcano |
| volcano built by atlernating explosive and quiet eruptions that produce layers of tephra and lava; found mostly where earth's plates come together and one plate sinks below the other | composite volcano |
| bits of rock or solidified lava dropped from the air during an explosive volcanic eruption; ranges in size from volcanic ash to volcanic bombs and blocks | Tephra |