What % of both water and land is Earth consist of?
29% land & 71% water
Out of the four main basins, which one is the largest?
Pacific Ocean
Mapping the ocean floor: Bathymetry
Measurement of ocean depths & topography of ocean floor
Mapping the ocean floor: Sonar
Sound, navigation, & ranging
Echo Sounder
reflects sound from ocean floor
Side-Scan Sonar
develops a picture of seafloor, but doesn't provide depth
Multibeam Sonar
obtains a wide high resolution profile of seafloor & provides depth
Satellites w/ radar altimeters
Mountains produce elevated areas, trenches produce depressions, caused by gravity
Seismic reflection profiles
used to view rock structure below sediments, & sound waves penetrate sea floor & bounce off rock layers & faults
Ocean floor provinces
continental margin, deep ocean basin, MOR
Passive continental margins
along coast of Atlantic Ocean, not associated w/ plate boundaries
Continental Shelf
gently sloping submerged portion of continental margin. May have glacial deposits & may be dissected by shelf valleys
Continental Slope
seaward edge of shelf, boundary between continental & oceanic crust.
Submarine canyons
deep, steep-sided valleys cut into continental slope
Turbidity currents
downslope movements of dense, sediment-laden water, where it deposits turbidites (exhibit gradded bedding)
Continental Rise
Continued slope merges into gradual incline, no trenches, turbidity currents deposit sediment forming deep-sea fans
Active Continental Margins
Around Pacific Ocean, continued slope descends into the deep-ocean trench.
Accretionary wedge
chaotic accumulation of deformed sediments & scraps of ocean crust
Deep Ocean Basin: Deep ocean trenches
long, narrow, deep, Pacific Ocean, associated w/ volcanism
Abyssal plains
Flat leveled, thick sediment
Seamounts
Submarine volcanoes
Guyots
submerged flat-topped seamount
Atoll
continuous or broken ring of coral reef surrounding a central lagoon
Mid-Ocean Ridge
elevated b/c new crust is hot w/ low density
What are the types of sea floor sediments?
Terrigenous, Biogenous, & Hydrogenous sediments
Terrigenous Sediments
Material Wx from continental rock
Ex: Clay
Biogenous Sediments
Shells/skeletons of marine organisms
Ex: Calcareous oozes, Siliceous oozes, & Phosphate-rich
Hydrogenous Sediments
Minerals that crystallize directly from seawater
Ex: Manganese nodules, Calcium Carbonates, & Evaporates
Seafloor Sediments & Climate Change
Seafloor sed. are recorders of climate change, contain remains of near-surface organisms that once lived at ocean-atmosphere interface, & numbers & types of organisms living at surface change w/ climate
Ocean Acidity
Humans increase atmospheric CO2: CO2 dissolved in seawater= carbonic acid (H2CO3), low pH levels makes seawater more acidic.
What % of both water and land is Earth consist of?
29% land & 71% water
Out of the four main basins, which one is the largest?
Pacific Ocean
Mapping the ocean floor: Bathymetry
Measurement of ocean depths & topography of ocean floor
Mapping the ocean floor: Sonar
Sound, navigation, & ranging
Echo Sounder
reflects sound from ocean floor
Side-Scan Sonar
develops a picture of seafloor, but doesn't provide depth
Multibeam Sonar
obtains a wide high resolution profile of seafloor & provides depth
Satellites w/ radar altimeters
Mountains produce elevated areas, trenches produce depressions, caused by gravity
Seismic reflection profiles
used to view rock structure below sediments, & sound waves penetrate sea floor & bounce off rock layers & faults
Ocean floor provinces
continental margin, deep ocean basin, MOR
Passive continental margins
along coast of Atlantic Ocean, not associated w/ plate boundaries
Continental Shelf
gently sloping submerged portion of continental margin. May have glacial deposits & may be dissected by shelf valleys
Continental Slope
seaward edge of shelf, boundary between continental & oceanic crust.
Submarine canyons
deep, steep-sided valleys cut into continental slope
Turbidity currents
downslope movements of dense, sediment-laden water, where it deposits turbidites (exhibit gradded bedding)
Continental Rise
Continued slope merges into gradual incline, no trenches, turbidity currents deposit sediment forming deep-sea fans
Active Continental Margins
Around Pacific Ocean, continued slope descends into the deep-ocean trench.
Accretionary wedge
chaotic accumulation of deformed sediments & scraps of ocean crust
Deep Ocean Basin: Deep ocean trenches
long, narrow, deep, Pacific Ocean, associated w/ volcanism
Abyssal plains
Flat leveled, thick sediment
Seamounts
Submarine volcanoes
Guyots
submerged flat-topped seamount
Atoll
continuous or broken ring of coral reef surrounding a central lagoon
Mid-Ocean Ridge
elevated b/c new crust is hot w/ low density
What are the types of sea floor sediments?
Terrigenous, Biogenous, & Hydrogenous sediments
Terrigenous Sediments
Material Wx from continental rock
Ex: Clay
Biogenous Sediments
Shells/skeletons of marine organisms
Ex: Calcareous oozes, Siliceous oozes, & Phosphate-rich
Hydrogenous Sediments
Minerals that crystallize directly from seawater
Ex: Manganese nodules, Calcium Carbonates, & Evaporates
Seafloor Sediments & Climate Change
Seafloor sed. are recorders of climate change, contain remains of near-surface organisms that once lived at ocean-atmosphere interface, & numbers & types of organisms living at surface change w/ climate
Ocean Acidity
Humans increase atmospheric CO2: CO2 dissolved in seawater= carbonic acid (H2CO3), low pH levels makes seawater more acidic.