Oceans Final

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Most trenches are in which ocean?: Pacific
Sediment is delivered to the deep ocean floor via...: -avalanches in submarine canyons -wind blown clay/dust -dead bits of marine animals
Hydrothermal Vents on the MOR result from...: Circulating groundwater in the oceanic crust is heated (usually) by a volcanic system underlying the ridge axis
Trenches are found at...: active continental margins.
The Gulf Stream is an example of heat transfer via: by convection (advection)
Waves on the surface of the ocean are what type of wave?: Orbital waves
The dispersion of waves is caused by ___________.: The relationship between wave speed and wavelength
How do prokaryotes and eukaryotes differ?: Eukaryotes have a nucleus in the cell that contains genetic material.
What produces longshore currents?: Waves approach the beach at a consistent angle.
What do drowned estuaries and Fjords have in common?: They are â€˜carvedâ€™ out of the coast during times of glaciation and low seawater levels.
Are there more animals in the oceans or plants/protists?: Animals
T/F Sunlight is required for trophic pyramid: FALSE - nutrients and autotrophs are required though
Alfred Wegener: first to propose that the continents were once all joined in a supercontinent called Pangaea, CONTINENTAL DRIFT THEORY
Erth\'s magnetic field is caused by: convection in the outer core
Vine and Matthews: showed that sea floor spreading operates in the oceans by examining the magnetic patern preserved in the oceanic crust
Hydrotectonic cycle: Transfer of water between Earths deep interior (asthenosphere) and exterior. Water is transferred to teh asthenosphere during subduction. Powered by heat from the core.
Tuzo Wilson: Plate tectonics - he predicted that earthquakes would ccur along transform boundaries, and not along fracture zones
What causes the change in elevation or topography across the fracture zones?: Teh difference in age of the plate across teh fracture zone (older sinks deeper)
Subduction action to drive plate motions: subducting slab pulls the trailing plate down the subduction one as it sinks under the force of gravity into the asthenosphere
Tuzo wilson correctly reasoned that if subduction rates exceed spreading rates, then...: the ocean basin will shrink or close
Hydrothermal vents on MOR are from...: circulating groundwater in the oceanic crust that is heated by a volcanic system underlying the ridge axis
Where on the continental margins is teh transition from continental to oceanic lithosphere?: Under the continental slope
Why are abyssal plains so flat?: b/c thick accumulation of pelagic sediment cover the original topography of ocean floor
Atolls: coral reefs growing around completely submerged seamounts
Pacific ocean has thin layer of calcareous ooze preserved, (compared to the atlantic) because....: a)the pacific has lower productivity of calcareous organisms, and b) the east pacific rise spreads fast so not much ooze can accumulate before it moves below the CCD and dissolves or is covered
Sediment deposited on the shelf is from...: marine pelagic sediment, terrestrial sedimentd from coastline, wind blown terrestrial sediment, terrestrial sediment from rivers.
biogenous sediments: includes coral growing in warm shallow seas, accumulate everywhere in the oceans where critters live, include outer skeletons from small photosynthetic orgs. and DO NOT only accumulate on the ocean floor in pelagic settings (open ocean)
Calcareous oozes are generally not present below 4500m water because: CaCO3 (mineral that makes calcareous ooze) dissolves below 4500 m
Siliceous diatomaceous sediments are: oozes found below 4500m in cold wter
Basic assumption in Science is: Physical laws are constant and do not change over time.
Uniformitarianism allows geologists to: evaluate rocks to determine the physical processes and conditions in Earth history
Nebular hypothesis tells us that the shape of the solar system results from: gravitational attraction of matter in teh nebula, internal pressure of gasses in the nebula, and the spinning nebula
difference in size (mass) and density between terrestrial and Jovian planets is from: temperature across the solar system and relative strength of teh solar wind
Origin of water in Earth\'s hydrosphere: Water was released through the earth\'s mantle via volcanoes
two factors prevented free water (h20) from existing on the surface of early earth: Distance from sun, mass of the Earth
which sources of heat caused the Earth to melt during accretion?: Compressional heat, collisional heat, radiogenic heat, NOT solar radiation
The Earth\'s core: formed from the segregation of iron liquid from silicate liquid during the magma ocean stage
Age of the Earth: 4.55 billions years
fossils help determine relative age of rocks because: they ocur in groups (assemblages) tht are distinctive of a time period
3 billion years ago, the only thing existing in the oceans would be: Bacteria!
how do we know the age of the earth: isotopic age dating of meteorites
When did oceans first appear on earth: 4.4 ga when tectonics began to operate on Earth
Patterson: Used marine sediment to date earth and compare to isotopic age dating of meteorites
oldest fossil evidence for life on Earth: 3.5 billions years old
Radioactive decay is used to measure absolute age because...: ratio of daughter to parent isotopes changes with time
What is produced during radioactive decay of an unstable isotope?: Heat, radiation (particles expelled from nucleus), a new nucleus (daughter atom)
Rutherford: First understood the process of radiogenic decay and described it with equations, suggested it could be used to date the earth
Bacquerel: first to observe radiation
The rate of decay of radioactive isotopes is: a function of the number of parent isotopes present
who won a noble prize for the study of radioactivity?: Bacquerel, m. curie, p. curie, rutherford
what direction does the earth rotate?: EAST
What source of Energy powers the Hydrologic Cycle?: Solar Radiation
Most of Earth\'s fresh water exists where?: as solid ice in glaciers
Hydrologic cycle: transfer of water between the atmosphere, oceans and continents
What percent of hydrosphere is contained in the oceans?: 97%
What represents the roughness/topographic relief of the Earth?: A Basketball
What are factors influencing the shape of the Earth?: Newton\'s Frist Law and momentum from rotation, Earth spins on its axis, location of continents on the globe, gavity, NOT Atmospheric pressure
Which ocean has greatest surface area, volume and depth?: Pacific
Smallest ocean by volume and area: Arctic Ocean
Average Depth of the oceans: 3.7 km
Which map best depicts greenland?: a conical, North pole projection map
What helps determine longitude?: time in greenwich England, the time where you are, fact that the Earth rotates 15degrees an hour or 360 degrees every day
Gas hydrates: contain more than twice the organic carbon stored in all other fossil fuels combined
How might methane gas hydrates effect climate change?: Melting gas hydrates may combat global cooling when shringking oceans expose the contintntal shelf, and melting methane gas hydrates may enhance global warming when expanding oceans melt arctic tundra
What happens to heat as sea ice melts in the arctic ocean during spring?: Heat from the ocean and atmosphere is consumed by the ice as it melts.
Greenhouse effect: heart is radiated to the atmosphre where it is absorbed by greenhouse gasses. This heat is the reradiated back to the surface where it is then reradiated back to the atmosphere
burning of fossil fuels would release fast amounts of co2 and affect marine ecosystems how?: cause increase in ocean acidity and damage many species of phytoplankton, disrupting food webs
Coriolis Effect: results in teh Easterly Trade winds, causes deflection of atmospheric circulation patterns both aloft and over the surface, results from teh decrease in linear spee of rotation iwth incresing latitude and DOES NOT result in humid tropical regions and arid mid-latitudes
Rotation of a tropical cyclone is: CAUSED BY THE CORIOLIS EFFECT
T/F Water vapor increases the density of air in the atmosphere: FALSE
Ekman flow in the southern hemisphere is: 90 degrees to the left of the wind direction
Western boundary currents: strong currents on the western side of oceans, caused in part by easterly trade winds piling surface water against a continent, found in all major oceans, exemplified by gulf stream which is the strongest and largest of all western boundary currents
increase in seawater density can be caused by: caballing (mixing of seawater in isopycnals), cold air blowing over the open ocean, formation of sea ice
Thermohaline circulation is driven by: variations in seawater density
formation of Anatarctic Bottom Water is due to: Formation of antarctic sea ice
cause of El Nino is linked to: flow of abnormally warm water from the western pacific to easter pacific
Common surface waves are caused by: wind
TF the speed of a shallow water wave changs with depth, but the length of a wave does not change: FALSE
In an orbital wave, why does the diameter of an orbit decrease with depth?: Because energy is not transferred efficiently with depth
A: A
Why do waves approach beaches consistently from one direction?: Because atmospheric circulation is consistent and thus waves are too
Today is sea level high or low and why?: High! We are at an interglacial period with reduced glaciers
What are Coast Circulation Cells: length of beach where supply of sediment balances the amount lost - sediment is supplied by rivers or coast erosion, and the deflection of longshore current disrupts the balance. Creates canyons or dams
Describe beaches in summer: low energy; gentle waves and winds. Sand is deposited on the beach and beaches grow
Describe beaches in winter: big storms, high winds and waves (high energy). Beaches erode, sand moves to offshore region
Barrier islands: dunes from last glacial maximum during low sea level. Now partly submerged as sea level rises. In constant motion.
What are the factors influence sea level?: glaciation, tectonics, global warming
Headland erosion: (Refraction of waves) wave energy focused onto headland, causing erosion. Causes straightening of shorelines, creates stacks and arches.
Beach drift: sediment is transported down the beach; swash and backwash
Longshore current: produced by waves approaching at an angle. Transports sediment along the coast in large bars within the offshore and nearshore regions
Groins and jetties, seawalls: attempts to stabilize beaches and protect from erosion; trap longshore transports of sand, starve down current beaches of supply and causes erosion
Beach replenishment: Expensive, fine sand washes away. doesn\'t stay very long.
Drowned estuary: during glacial maximum, rivers channel move onto shelf, they are flooded now that sea level is high; Chesapeake bay
Fjords: glacial cut valleys, still, protected from open ocean
Bar-built: spit or bar encloses bay
Tectonic: Plate motions (faulting) blocks sound
How do natural coastlines and estuaries benefit us??: estuaries Protect the coastline; Grasses and mangroves prevent storm damage to coast
Biodiversity vs. time: biodiversity of important marine ecosystems is declining. This trend is projected to result in complete collapse of commercial seafood fisheries by 2048. Time remains to fix this problem
Prokaryotes: no discrete nucleus material
Archaeobacterea: Prokaryote â€¢ Some are extremophiles â€“ Live in hot springs, hydrothermal vents, glacial ice; Some are Chemotrophic â€“ S- or CH4- reducing
Eubacteria: Prokaryote, \'true bacteria\', includes cyanobacteria
How much of all organic matter do euacteria and archea make up?: 50%!!!!
Protista: Eukaryotes-have nucleus with genetic material. Unicellular to simple multicellular. Most Algae and phytoplankton
Plantae: Eukaryote, multicellular, reproduce sexually, photosynthetic
Where do plants and protists mainly reside?: 96% terrestrial, 4% (11,000) marine (mostly algae/plankton)
Fungi/Mycota: Eukaryotes; feed on decaying organic matter; genetically closer to animalia than plantae
Animalia: Eukaryotes, multicellular; Consumer other oranisms, 80% terrestrial
Autotrophs: synthesize own food; primary production; photosynthetic/ chemotrophic; base of food web!
Photosynthetic: combine solar energy with nutrients to grow tissue
Chemotrophic: extract energy from chemical reactions.
Phytoplankton: protists; autotrophic component of the plankton community; protists/eukaryotes
Heterotrophs: eat other oranisms, herbivores omnivors
Pelagic: live in water; planktonic = float, nektonic = swim
Benthic organisms: live in substrate (coral and shiz) epifannal live on surface like starfish; enfaunal live/burrown in substrate (clam and oysters)
Oldest fossils: 3.5 billion years old
first evidence for life: 3.9 Ga - organic molecules in sediment, rich in carbon, a poduct of photosynthesis
Early atmosphere: reducing environment, no ozone,
Traditional concept of origins of life: Miller & Urey; simulated reduced atmosphere and primordial ocean, added energy; --formed amino acids, organic molecules. Later FOX created similar experient-created polymers of amino acids, proteins, RNA, fatty acids adn lipids required for cells. also found in meteroites.
Wacky idea about meterorites: added amino acids/lipids to the atmosphere and help bring life here.
Problem with traditional concept of origins of life: UV-B would destroy life because there is no ozone
Newer concept of origin of life on Earth: Heterotrophs liveing off primary producer (chemotrophic bacteria which get energy from reducing methane and sulfur) that is independent of the sun
Stromatolites: oldest macrofossil, 1.75 b.y., communities of cyanobacteria
Oxygen comes into atmosphere: 2 billions years ago; oxygen is \'great electron thief\'= oxidation. BUT after so much of the crust was oxydized, oxygen became concentrated in the atmosphere.
Great Oxygen Holocaust: oxygen is toxic to most life before 1.9 Ga (anaerobic) so it\'s concentration in the atmosphere killed many bacteria---leads to rise of Eukaryotes!
First Eukaryote fossils: 1.85 b.y. old, acritarchs (simple unicellular, photosynthetic), formed from symbiosis from bacteria
origins of Multicellular life: 600 Ma, Cambrian Time - caused by..global glaciation, rise in o2, first plate spreading?? likely reasons
Oldest evidence of life on Earth: Carbon-bearing minerals with isotopic composition indicative of organic matter
Primary Producers â€“ synthesize organic molecules from inorganic nutrients (phytoplankton) â€“ Feed other organisms (zooplankton) â€¢ Most are photosynthetic - previous map of chlorophyll = map primary production: â€“ synthesize organic molecules from inorganic nutrients (phytoplankton) â€“ Feed other organisms (zooplankton) â€¢ Most are photosynthetic - previous map of chlorophyll = map primary production
What does photosynthesis produce?: Glucose and oxygen
What is meant by primary productivity: The conversion of inorganic molecules into organic molecules.
Productivity increases in summer in High latitudes because: Nutrients brought to surface during winter overturn â€“ Stable upper water column during summer â€¢ Melting sea ice â€¢ No vertical mixing â€“ Perfect for phytoplankton bloom
productivity in Mid-latitudes: Nutrients brought to surface during winter overturn ⬢ Spring bloom - solar radiation increases ⬢ Grazing lowers productivity in late spring -----Nutrients are high in winter b/c of vertical mixing, and low in summer due to consumption by producers ⬢ Notice biomass lags behind nutrients - b/c of required solarradiation
Productivity in the Tropics: Small summer bloom -productivity is low b/c : Nutrients are limited! ⬢ No vertical mixing during change of seasons ⬢ Thus, nutrients are not cycled to photic zone.
Greatest productivity in the oceans: Upwelling zones (high latitudes and coastal); concentrated in space and time
Lowest productivity in oceans: open ocean,
Marine productivity vs. terrestrial productivity: upwelling zones and estuaries have similar amount of productivity as rain forests; dense with life
HAB (Harmful Agal Blooms) / Nutrients and Dead Zones: Over abundance of nutrients - too many phytoplankton which die/sink, and are consumed by bacteria. Bacteria consume all 02 during respiration, killing aerobic organisms; during summer dead zone increases; annual dead zone; fertilizers flow from mid-continent through river to gulf of mex.
Zooplankton: primary consumers, herbivore plankton, most massive pop. of herbivores on Earth, - convert all plant life to animal tissue; feed all carnivores
How much energy is transferred between trophic levels?: 10%. 90% is lost to metabolism, life, and decay
Chemosynthetic communities: base is chemosynthetic bacteria - use sulfur compounds to make organic molecules from co2 and o2. Live in water and crust

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