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Definition
| consists of thick accumulations of sediments that were deposited atop the low, rough portions of the ocean floor by turbidity currents. |
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| sediment from oceanic plate is plastered against the coninent to form a collection of sediment. |
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| active continental margin |
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Definition
| located around Pacific Ocean where edges are overunned by oceanic lithosphere. |
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Definition
(bathos=depth;metry=measurement)
measuremnt of ocean depths and the charting of the shapre or topography of the ocean floor. |
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| a hydrothermal vent on the ocean floor that emits a black cloud of hot, metal rich water. |
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Definition
| subduction in which the angle of descent is small because the oceanic lithosphere is still warm and buoyant. it occurs where a spreading center is near a subduction zone. |
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Definition
| portions of the seafloor adjacent to the continents. |
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| linear zone along which continental lithosphere stretches and pulls apart. its creation may mark the beginning of a new ocean basin. |
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regions where trenches do not exist, relatively steep slope merging into a gradual incline. consist of sediments that move downslope into the continental shelf to the deep ocean floor.
passive continental margin. |
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Definition
gently sloping, submerged surface extending from the shoreline toward a deep ocean basin.
passive continental margin. |
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Definition
true edge of the continent has a steep slope that leads from the continental shelf into deep water.
passive continental margin. |
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Definition
| loacted between continental margins and oceanic ridge systems. features include deep ocean trenches, abyssal plains, seamounts & oceanic plateaus. |
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Definition
| long narrow depressions that are the deepest part of the ocean and located where moving crustal plates descend back into the mantle. |
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| a cone-shaped deposit at the base of the continental slope. the sediment is transported to the fan by turbidity currents that follow submarine canyons. |
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Definition
| signals bounced off the ocean floor that measure water depth. |
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Definition
| a submerged, flat-topped seamount. |
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Definition
| site of seafloor spreading. foudn in all major oceans and represents more than 20% of Earth's surface. characterized by: elevated position, extensive faulting, & volcanic structures developed on newly formed oceanic crust. various segmentss of oceanic ridge is controlled by rate of seafloor spreading. |
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Definition
| an extensive region on the ocean floor composed of thick accumulations of pillow basalts and other mafic rocks that in some cases exceed 30 km in thickness. |
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Definition
| area where uppercrust is composed of pillow lavas of basaltic composition. layer below are interconnected dikes called sheet dike complex underlain by a thick layer of gabbro. |
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Term
| passive continental margin |
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Definition
| margin that consists of a continental shelf, continental slope, and continental rise. they are not associated with plate boundaries and therefore experience little volcanism and few earthquakes. |
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Definition
| basaltic lava that solidifies in an underwater environment and develops a structure that resembles a pile of pillows. |
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Definition
| long narrow trough bounded by normal faults. it represents a region where divergence is taking place. |
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Definition
| volcanic peaks on the ocean floor that originates near oceanic ridges or in association with volcanic hot spots. |
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Term
| seismic reflection profile |
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Definition
| profile of strong low-frequency sounds produced by explosions (depth charges) or air guns. the sound waves penetrate beneath seafloor and reflect off the contacts between rock layers and fault zones. |
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Definition
| layer below the pillow lavas of a ophiolite complex of interconnected dikes underlain by a thick layer of gabbro. |
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Definition
| acronym for sound navigation and ranging. helps in measuring water depths. |
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Definition
| a submerged, flat-topped seamount. |
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