Oceans: estuaries, ocean movement, seafloor features

Estuary
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Terms in this set (46)
Estuary
The area where a freshwater stream or river merges with the ocean
Phytoplankton
Photosynthetic algae found near the surface of the ocean
Coastal Plain Estuary
Former river valley now flooded with seawater
Tectonic Estuary
An estuary that results from the sinking of land due to movements of the crust
Subside
The sinking or downward motion of Earth's ground
Bar Built Estuary
An estuary / shallow lagoon separated from the open ocean by a bar deposit such as a barrier island (e.g. Pamlico Sound, NC)
Fjord Estuary
Former glaciated valley now flooded with seawater
Current
Continuous and directed movement of ocean water
Surface currents
10% of water in ocean
Deep water currents
90% of water in ocean
Surface currents are driven byWindDeep water currents are driven byDensity (temperature and salinity)Density CurrentCirculation pattern in the ocean that forms when a mass of more dense seawater sinks beneath less dense seawaterThermohaline CirculationMovement of ocean water caused by density difference brought about by variations in temperature and salinityPrimary ForcesStart water movementSecondary ForcesInfluence where currents goSolar heatingCauses water to expandCoriolis EffectThe effect of Earth's rotation on the direction of winds and currents.GyresHuge circular moving current systems dominate the surfaces of the oceans.Ekman TransportThe water movement 90 degrees from the wind directionUpwellingThe movement of deep, cold, and nutrient-rich water to the surfaceLongshore Currenta current that flows parallel to the shorelineRip Currenta relatively strong, narrow current flowing outward from the beach through the surf zone and presenting a hazard to swimmers.WavelengthHorizontal distance between the crests or between the troughs of two adjacent wavesTroughLowest point of a waveCrestHighest point of a waveWave heightthe vertical distance from the crest of a wave to the troughTidesthe regular rise and fall of the ocean's surface influenced by the moon's gravity pulling on earthLunar TideMore than 2x as high as those caused by the sunSolar TideCan either enhance or diminish lunar tidesSpring TideOccur when the Sun, Moon, and Earth are aligned, causing high tides to be higher than normal and low tides to be lower than normalNeap TidesHigh tides are lower and low tides are higher than normalContinental Marginthe zone of transition between a continent and the adjacent ocean basin floorOcean basin floorbetween the continental margin and mid-ocean ridgeMid-ocean ridgecenter of most ocean basins; underwater mountain rangeSea MountUnderwater mountains below the sea surface, which are made up of rocks and sedimentAbyssal Plaina large, flat, almost level area of the deep-ocean basinSeafloor SpreadingThe formation of new ocean crust as a result of magma pushing upward and outward from Earth's mantle to the surface.Hydrothermal Ventsan opening in the sea floor out of which heated mineral-rich water flows.Guyota seamount with a flat topSedimentationthe process of settling or being deposited as a sediment.JettyA structure that projects into the water and protects the shoreBreakwaterA structure protecting a nearshore area from breaking waves.Groinsshort, artificial walls built perpendicular to the shoreline to trap sand moved by longshore currents.Seawallswalls built parallel to the coast to block waves before they hit the shoreLeveea wall of earth built to prevent a river from flooding its banks