Download Important Oceanography Stuff

Survey
yes no Was this document useful for you?
   Thank you for your participation!

* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project

Document related concepts

Soil salinity control wikipedia , lookup

Geochemistry wikipedia , lookup

Post-glacial rebound wikipedia , lookup

Water pollution wikipedia , lookup

Sea wikipedia , lookup

Anoxic event wikipedia , lookup

Global Energy and Water Cycle Experiment wikipedia , lookup

Geophysics wikipedia , lookup

Air well (condenser) wikipedia , lookup

Marine biology wikipedia , lookup

Deep sea community wikipedia , lookup

Plate tectonics wikipedia , lookup

Marine pollution wikipedia , lookup

Ocean acidification wikipedia , lookup

Geological history of Earth wikipedia , lookup

Nature wikipedia , lookup

Abyssal plain wikipedia , lookup

Paleoflooding wikipedia , lookup

Ocean wikipedia , lookup

Physical oceanography wikipedia , lookup

Transcript
Oceanography
CH1
70.8% earth is ocean.
97% earth water in ocean
observe, hypo, test, theorize
3729m avg. ocean depth
Density Stratification: more dense material migrates to middle of earth
Differentiation: process by which dif layers form, microgomical life.
oceans provide 70% of breathable oxygen
½ earth pop. live coastal
80% Americans hour from water
Pacific, Atlantic, Indian, Arctic, Southern/Antarctica
Mauna Kea: tallest mountain from base to top
Polynesia, Micronesia, Melanesia
nebula: cloud gas/dust
nebular hypothesis: big ass sun, left behind pieces, thus, we are fecal matter of a super
novial basis.
fusion reaction: tens of millions of degrees
solar wind: ionized particles of the sun
radioactivity: spontaneous disintegration of atoms
Crust: granite, basalt.
Oceanic crust: basalt thinner, more dense 5m
continental crust: granite. thicker, less dense 22m
Mantle: lithosphere, aesthenosphere, mesosphere. 1800m
lithosphere: crust, top portion mantle. 62m thick
asthenosphere: plastic, flow if force applied. 62m-430m.
mesosphere: 430m-1800m. rigid, deforms platically.
inner core: rigid
outer core: liquid
Isostatic adjustment: the verticle movement of crust
isostatic rebound: when reduced load causes area to rise
outgassing: when lower density gases from within are expelled from inside. [water vapor
condensed and formed first oceans.
oxygen comprises 21% atmosp
Stanley Miller: conducted first experiment of early atmosphere.
Heretotrophs: earliest forms of life. fed on non-living organic food.
autotrophs: made own food. similar to anaerobic bacteria
chemosynthesis: process by which energy from deep water hydrotherm vents
chlorophyll: green pigment captures sun through photosynthesis.
endothermic: engery got through chemical processes
exothermic: energy released through chem. proc.
autho and hetero need each other
From the very beginning, life depended upon life.
half-life: time it takes for ½ the atoms in a sample to decay to other atoms
radiometric age dating: comparison b/w radioactive material and amount of resulting
decay.
4.6b yrs ago earth created. 4b yrs ago oceans created.
1 degree of lat=60 nautical miles.
1 degree long is variable
60m long at eq, 0 at poles
CH2
Alfred Wegener 1912: continental drift, pangea
200m yrs ago continents one
low lat similarities b/w glacial deposits
did not have good explanation of plate tectonic theory
1960s after WWII new data.
ecosounding:pings
paleomagnetism: to determine original positions of rocks on earth
magnetic field exists b/c convection in earth’s core
lava-no mag field
“currie” temperature=magnetism
field flips now and again
magnetameters: used to measure field
striped ocean floor indicates flipped magnetic field over ages of sea-floor spreading
Harry Hes: Plate Tectonics; subduction theory, sea-floor spreading
200m yrs oldest lithosphere
pacific ocean shrinking, atlantic growing
earthquakes match plate boundaries
Sir Edward Bullard put continents together at 2000m depth instead of at coastlines.
magnetite: naturally magnetic iron material
magnetic dip: degree to which magnetite particle points into earth. Parallel at Equator.
polar wandering curve: curve that shows change of position of poles through time
magnetic anomalies: ocean floor stripes of magnetite frozen in various rocks, showing
change in polarity of magnetic field
convection cell: asthenosphere circular moving loop of matter involved in convective
movement
Fredrich Vine and Drummon Mathews: explained earth’s switching polarity with sea
floor spreading
oldest ocean floor 180m yrs
crust thinner by MOR, thicker by trenches
all plates contain oceanic and continental crust
rift valley 25-50km wide
oceanic ridges and rises are slow spreading and steeper. and narrower
shallow heat source-> upwelling, then movement apart creates rift valley, then linear sea
is formed with increase spreading. millions of yrs later big ocean, continents.
rate of spreading varies along MOR
faster spread, les ruged terrain, b/c undergoes less thermal contraction and subsidence
oceanic rises: gently-sloping, fast spreading parts of MOR
east pacific rise: b/w pacific and Nazca plates; broad, low, gently swelling floor with
indistinct rift valley: 16.5 cm/yr spread rate.
oceanic ridges: steep-sloped slow spread
faster spreading=less energy per earthquake
seismic moment magnitude: measure earthquake intensity Mw.
Mw=6.0 slow spreading mid-atlantic
Mw=4.5 fast spreading east pacif-ridge
volcanic arc; volcanoes above subduction zone
continental arc: oceanic-continental collision [basalt+granite=destructive eruption
island arc: oceanic-oceanic collision; older, denser sea floor subducts
[basalt+baslt=not destructive]
older continental lithosphere no denser than young
continental-continental no subduction, high mountains result
trench earthquakes occur in succession
subducting plate can be traced below surface by measuring seismic activity by depth
factors of convergent boundary earthquakes:
-lithospheric slabs of rock pressing together
-thick crust of convergent boundaries more energy than thinner crust of div
boundaries
-mineral structure changes occur at deeper, higher pressures
transform fault: a fault with side to side motion that offsets segs of MOR
oceanic transform fault: most common, occurring on ocean floor
continental transform fault: cuts across continent
transform faulting: movement of 1 plate past another; shallow, strong quakes in
lithosphere
san andreas fault: continental fault from gulf of cali to n cali. Mw=8.5. Cali will NOT fall
into ocean
intraplane features: features within plate far from boundaries
mantle plumes: columnar areas of hot molten rock that arise from deep within mantle
hotspots; come to surface
Iceland above a 93m wide mantle plume.
Hawaiian Islands-Emperor Seamount chain; NW-ward-SE-ward. 100 volcanoes. Mantle
plume remains, and the plates move
one hotspot created many
Nematath: a chain of extinct volcanoes older as further from hotspot
Hawaiian islands eventually will subduct into Aleutian trench
Loihi: volcano to take place of hawii.
Seamount: tall, volcanic, conical peak [abyssal=<200m]
tablemount: tall, volcanic, flat peak.
-Tablemounts forms by seamounts carried from MOR volcanic centers and sometimes
become islands. Wave erosion flattens seamounts. carried into deep water, taking w/
them evidence of shallow water days
Coral Reef:
Calcareous reef 18 degree C
Darwin theorized firstly about reefs
3 stages of formation:
-fringing reefs; develop along margin of a landmass, where temp, salintity
and turbidity of water suitable for reef-building corals. Volcano lava kills fringing reef
often, so not very developed. If lvl of sea remains constant or land does not sink, then
process stops at fringing reef stage.
-barrier reefs: separated from sunken landmass by well-developed lagoon.
reef grows 3-5m per 1000 yrs. if landmass sinks faster than coral can grow, depth will not
support reef life.
-atoll: atoll encloses lagoon 30-50m deep, channels to open ocean. volcano
completely sunk. Can support human colonization.
Great Barrier Reef- 3000+ indiv reefs. 25m offshore. 90m width. 1200m long.
northerly part oldest, because it reached appropriate water first.
Paleogeography; study of historical changes of continental shapes and positions.
paleoceanography; study of phys shape, compos, char of oceans brought about by
paleogeography changes.
Wilson Cycle: uses plate tectonic processes to show the distinctive life cycle of ocean
basins during their formation, growth, and destruction.
[lecture]
-go N, magnet points down, S points up
-500k yrs in interval of magnetism reversal.
-normal polarity, magnetism leaves S, enters N.
-90% earths field is dipolar
-90% earth’s heat from radioactivity in mantle.
-10% latent heat stored in earth’s core.
-ongoing convection creates differentiation
-iron catastrophy; iron to middle of earth
-early atmosp and oceans created by volcanic activity
-transfer heat 3 ways; radiation, conduction, convection
-Wilson Cycle;
embryonic; uplift
juvenile; divergence [narrow sea]
mature; divergence [ocean basin]
declining; convergence [sub island arc]
terminal; convergence [collision]
suturing; convergence and uplift
CH 3
bathymetry; measure of ocean depths
sounding; weight on a line
fathom; 6th; standard unit of ocean depth
relief; variations in elevation
HMS Challenger; 1872; 1st ship to make systematic soundings
echo sounder; ping
Precise Depth Recorder; sonar tech; high freq sound beam to measure depth
sonar; sound navigation and ranging
seabeam; 1st multibeam echo sounder
Sea MARC; side-scan sonar sys; Sea Mapping and Remote Characterization [towed]
GLORIA; side-scan; Geological Long-Range Inclined Acoustical instrument [towed]
5% of ocean floor mapped as precisely as moon surface
satellite bathymetry measures relief in ocean surface; high sub-contours produce bulges
seismic reflection profiles: sounds which penetrate the sea floor and reflect off of
boundaries b/w different layers of rock/sed
hypsographic curve:relationship b/w height of land and ocean depth
ocean floor:
-continental margins; shelf, slope, rise
-deep-ocean basins; further from land
-MOR; near middle ocean, shallow
continental margins;
passive margins: little tectonic activity, interior of lithospheric plates. [not close to
any plate boundary]
active margins; much activity, close to plate boundary.
convergent; ocean-continent convergent plate, continental arc, narrow
shelf, steep slope, offshore trench
transform; transform plate boundaries. faults that parallel transform plate
boundary create linear islands, banks, and deep basins close to shore.
continental shelf; underlying rock is continental crust. flat zone from shore to sharp slope.
shelf break; marked slope angle increase at end of shelf.
-70km avg width
-largest shelves shores of N sibera, NA
-135m avg. depth
-antarctica shelf break at 350m
-avg slope a 10th of a degree
-continental slope determined by continental margin
-continental borderland; when offshore faults of an active transform margin creat
a CS that is not flat
continental slope; where deep-ocean basins begin
-avg slope 4 degrees, varies 1-25 degrees
Submarine canyons; V-shaped, continental shelf and slope.
-Montery Canyon=grand canyon
-not formed by rivers, by but turbidity currents
turbidity current; underwater avalanche of muddy water w/ rocks
Continental rise; transition zone b/w continental margin and deep-ocean floor, much
debris.
graded bedding; grades in size upward. caused by turbidity currents.
turbite deposits; graded beeding, continental rise is composed
deep-sea/submarine fans; deposits at mouth of submarine canyons.
Indus fan burries Carlsberg Ridge
along convergent active margins, no continental rise.
abyssal plain; plains from rise to ocean-basins. Flat, w/ slopes fraction of degree.
-4500m-6000m deep
-few abyssal plains in pacific b/c of trenches
suspension settling; fine particles accumulate on ocean floor. Covers irregularities.
abyssal hill/sea knoll; less than 1000m high
-most abundant features on planet
abyssal hill prvinces; regions of abyssal hills due to low sed deposition; pacific.
ocean trench; deep linear scars caused by plate collision
Pacific Ring of Fire; along margins of pacific, maj of volcanoes and earthquakes.
MOR; 46,600mile long. avg width;620m, avg 1.5m high. 23% of earths surface, entirely
volcanic.
rift valley; contain fissures and faults
pillow lavas/pillow basalts; frozen lobes of magma when in quick contact with cold
ocean water.
80% earth volcanism on seafloor
3 cubic miles of molten rock erupts on sea floor each year.
hydrothermal vents; feature of central rift valley; hot springs. seawater along fractures in
crust seeps down, becoming heated when close to magma, then rises to floor again.
warm water vents; below 86 degrees F, clear-color water
white smokers; 86-662 degree F, white b/c of light-colored compounds
black smokers; above 662 degrees F, black b/c metal sulfides chimneys up to
200ft. No steam, b/c of pressure
metal sulfides; dark-colored; ion, nickel, copper, zinc
precipitate; solution out of which come the dissolved metal particles
-creates mineral deposits on nearby rocks.
-vents support unusual life
transform faults; cut mid-ocean ridge. Exist b/c spreading on spherical earth. Seismically
active, occur b/w offset segs of mid-ocean ridge
fracture zone; seismically inactive, occur beyond offset segs of MOR.
[lecture]
-earth radially stratified
-convection efficient way of transferring heat
-core; iron/nickel
-mantle; magnesium iron silica
mesosphere stronger than asthenosphere
-ocean water density; 1.028 g/cm3
-sea lvl S of Indian 100m lower than in pacific
-smooth out earth, add all water; 2440m mean earth depth [water world]
-when subducted lithosph reach 100mile depth, pent up water comes up and create
volcano
8 or 9 megathrust earthquakes; when locked plates slip
CH 4
sediment; eroded particles of dirt, dust, other debris scattered at ocean floor
cores; a cylinder of sed material recovered
past climate, geology, biology known by study of cores
more than half rocks on earth surface are sedimentary rocks [lithified sediments]
lithogenous sed; sed derived from weathering of rock and transported to ocean
weather, erosion, transportation, deposition, lithification
erode; picked up
carried to oceans by gravity, wind, streams, glaciers
most lithgen material around continents
minerals; discrete crystals of naturally occurring compounds
quartz; silicon and oxygen SiO2. abundant, chemically stable, durable
large -> small; boulders, cobbles, pebbles, granules, sand, silt, clay
sed size proportional to energy required to lay it down
[clay is exception, because they stick together]
winds carry 11-5m metric tons of sand to ocean per year
sorting; measure of the uniformity of grain sizes
-glaciers leave poorly sorted seds
-better sorting; more alike to surrounding sed
maturity; increases as
-clay cont decrease
-sorting increase
-non-quartz material decrease
-grains of dep more rounded
occurs during transport
beaches mature/glacial deposits immature
Neritic deposits; around continental margins and islands
Pelagic deposits; deep-ocean basin deposits
relict seds; cover the continental shelf
muddy lagoon, sand beach most likely to create litho sed rock
litho sed found in abundance in ocean trenches
grain composition not necessary to describe texture of sed
lithogen found also on abyssal plains, found everywhere
lithogen sed is THICK at cont, shelf, rise, and deep trenches
glacial deps; boulders to clays, poorly sorted. forming around Greenland and ant right
now. in high lat areas of continental shelf.
ice rafting;lithogen particles carried out by glacial ice
abyssal clay; compose deep ocean abyssal plains. 70% clay-sized particles from land
dominates not because clay settles most, but b/c other seds don’t
biogen sed; hard part remains of dead organisms
tests; tiny shells constant rain to ocean floor
ooze; 30% test material, 70% clay; sed on ocean floor
algae; organisms; photosynthetic, from single cells to giant kelp. Have membrane bound
nucleus
protozoans; single-celled, eukraytic, usually microscopic, not photosynthetic
calcium carbonate; forms calcite
silica; hydrated form called opal
diatoms; microscopic algae->give silica->found at surface with sunlight and planktonic
radiolarians; microscopic->gives silica->rely on outside food sources
[planktonic=free floating]
diatomaceous ooze; lightweight white rock of diatom tests and clay that has lithified. At
ocean floor where, above, diatoms are abundant
siliceous ooze; accumulation of siliceous tests of diatoms, radiolarians, and other silicaproducing organisms. [cool, cool surface high lat, upwelling brings cold water, beneath
areas of upwelling and along equator]
foramnifers; relatives of radiolarians. protozoans, planktonic, micro to macro, no photo,
hard tests produced
only foramnifers and coccolithophores are planktonic
coccolithophores; single-cells algae, planktonic, photosyn. produce spherical layer of
calcium carbonate
nannoplankton; 10-100x smaller than diatoms [calcium carbonte]
coccolith; individual plates of coccolithophores
chalk; when coccolith-rich ooze lithifies. England chalk cliffs lifted above sea
cretaceous period!
calcareous ooze; deps rich of foramnifer, coccolith tests [calcium carbonate] [warm,
warm surface, low lat, dissolves after CCD, war surface water, low lat along mid-ocean
ridge]
diatomaceous ooze resistant to heat [space shuttle]
biogen sed found in pelagic deps, rarely in neritic deps, but does exist
distribution of biogen sed depend on;
productivity
destruction
dilution
dilution; when deposition of other sed decrease percentage of biogen seds.
calcite compensation depth [CCD]; point at which sed does not usually contain much
calcite b/c it readily dissolves. usually 15k ft below sea lv, but varies. Siliceous
unaffected
calcareous ooze can survive lower than CCD if formed on MOR, and covered by other
seds, then taken out by sea-floor spreading
modern carbonate oozes rare below 16.4k ft
calcium carbonate rare in deep ocean or cold water
upwelling; when deep ocean water comes up and supplies nutrients
Neritic deps->continental, islandal
carbonate
limestones
most limestone contains fossile marine shells, suggesting biogen origin
ancient marine deps 2% earth’s crust, 25% of a sed rocks on earth
limestone forms bedrock and groundwater-percolated caverns
stromatolites;fine layers of carbonate, from in warm shallow water
cyanobacteria produce these deps; trapped particles in mucous mats
can be big
pelagic deps; oceanic
siliceous ooze 3 kinds; cool waters [cool, cool surface high lat, upwelling brings cold
water, beneath areas of upwelling and along equator]
diatomaceous; diatoms, cold water of poles
radiolarian ooze; radiolarians-> equatorial regions
silicoflagellate ooze; silicoflagellates
calcareous ooze; warm waters [warm, warm surface, low lat, dissolves after CCD, war
surface water, low lat along mid-ocean ridge]
coccolith ooze; colithopres
foramnifer ooze; foraminifer
moist of ocean covered by calcareous ooze, then abyssal clay, then siliceous
lysocline; depth where pressure and CO2 great enough to begin dissolving calcium
carbonate.
Evaporate minerals; form where open ocean circulation restricted and evap rates high.
tektite; small molten pieces of crust ejected into pace by terrestrial impact
oolite; small calcite spheres, shallow tropic water where CaCO3 high in concentration.
layers like onion
Metal sulfies; associated with vents and black smokers MOR. found all over, though;
iron, nickel, copper, zinc, silver
clay is a part of every sediment type
sed are rarely pure
most litho has biogen sed too
tiny amounts of cosmos ed with all types of sed
misc
KT event killed 2/3 plant/animal life [dinosaurs]
Deccan Traps; large outpouring of volcanic basaltic rock in India
Iridium; rock from meteors mainly
Chicxulub crater; Yuctan Penn, MX
99% of particles that fall to ocean floor do so in fecal pellets
dredge; bucket like device used to scoop up sed
gravity corer; hollow steel tube w/ weighted top; used to collect cores
rotary drilling; collect cores from deep ocean
petroleum; leftover remains of microscopic organisms buried and pressured 95% of econ
value of extracted non-living resources
30% of petroleum got from ocean today
gas hydrates; compact strucs of water, nat gas. occur under permafrost land areas and
under ocean floor
methane hydrate; produced my methane, most common nat gas
gas hydrates formed by bacteria breaking down organic matter traped in sea floor
seds
mostly in continental margins
sudden release of methane cause tsunami
sand and gravel; mined. second to petroleum industry. suction dredge.
concrete, beaches, fill material
gems and minerals too
salt deposits; precipitated salts
gypsum-casts, molds, wallboard, sheetrock
Halite; table salt, curring, preserving, dying, de-icing, agriculture, soap, matches,
fireworks
[Roman “salarium” -> salary. Roman soldiers paid in salt. Soldier “not worth his
salt”]
Phosphorite; sed rock of phosphate minerals. plant nutrient.
continental shelf, slope, 1k ft
many deps nodules
Manganese nodules; cobalt only “strategic” metal of the nodule. US uses for strong alloy.
crusts; hard coatings on other rocks
Deep Sea Drilling Project; confirmed sea-floor spreading. Today known as Integrated
Ocean Drilling Program
CH5
[lecture]
avg spread speed; 5cm/yr -> 20km/million yrs -> 20km3/yr of lava
atlantic spreading slow, pacific fast, but atlantic growing while pac shrinking.
water weakens asthenosphere
much life is mostly water 65-95% of bodies
water regulates global temp by
redistr heat
-storing energy /w out large temp variations
water a solvent
makes soil
salt water
atoms
neutrons [neutral]
protons [+]
electrons [-]
covalent bond; saring electrons, strong
angle b/w hydro atoms 105 degrees
unusual bend in geometry
polarity allows water to form weak hydrogen bonds with fellow molecules
b/c of polarity, water sticks to itself and other things
allows water to be universal solvent
hydrogen bonds strong enough to
high surface tension
high solubility of chem. compounds in water
solid, liquid, gas
unusual thermal properties
counter intuitive density
Temp is not heat.
water cools to 4 degree C
high boiling/high freezing
high latent heat; vaporization/condensation, melting/freezing, evaporation
water has high heat capacity
65% human made of water. 83% blood
quarks; smallest thing
atom holds same number prots, elecs
number of prots is what distinguishes elements known
molecule; group of 2+ atoms
dipolar; two poles of dif charges
cohesionl sticking to one another
mercury only thing with higher surface tension than water
water molecule can reduce attration b/w ions of dif charges by as much as 80%
electrostatic attration; creates ionic bond; b/w dif charges ions
hydrationl process by which water molecules completely surround ions
oil has no charge, which is why it is one of only thing water can’t dissolve
50 quadrillion tons of dissolved salt, the ocean has
van der Waals forces; weak interacting attraction significantly only when molecules are
very close togheter [solid, liquid states]. energy must be added to the molecules or ions so
that they can move fast enough to overcome these attractions.
heat; the energy of moving molecules
kinetic energy; energy of motion
combustion=burning
calorie; amount of heat required to raise 1g of water 1 degree C
temp; direct measure of the avg kinetic energy of the molecules that make up a substance
great the temp, greater the kinetic energy
water solid state does not conform to shape of container. Rigid, less dense than liquid
state.
liquid state; KE, so molecules flow past one another. conform to shape of
container.intermolecular bonds form and break at greater rate than in solid state.
vapor; water’s gaseous state. fill volume of container. flow freely, don’t interact except
collisions
melting point/freezing point=0 degrees C/ 32 degrees F
boiling point/condensation point=100 degrees C/ 212 degrees F
water condenses when enough heat is removed from a gas
normal compound melting (-90 degree C) boiling (-68 degree C)
water points higher, b/c more heat req to overcome hydro and van der waals forces
heat capacity; amount of heat req to raise of 1g of any substance 1 degree C
the higher heat capacity, the more temp-concerned it’s heat gain or loss is
metals and oil low heat capacity [change temp fast]
water evap from skin, cools it, because it takes heat with it
WATER HEAT CAP=CALORIE
latent heat of melting; energy needed to break intermolecular bonds that hold water
molecules rigidly in place in ice crystals [melting ice; this latent heat causes a plateau of
temp remaining unchanged until the rigid bonds break]
latent heat of freezing; heat released when freezing
latent heat of vaporization; plateau of 540cal/1g of water; amount of heat must be added
to 1g of sub at its boiling pt to break the intermolecular bonds to form gas.
latent heat of condensation; heat released when water vapor cooled and condenses of liq.
[heat release can cook, power hurricanes and storms]
sea surface avg temp > or = 20 degree C
evaporation; liquid to gas before boiling pt
molecules left behind lose heat to evaporated molecules
latent heat of evaporation; 585 cal/1g water. more heat req, b/c more hydro bonds to be
broken. [at high temps, less bonds, b/c molecules jostling about more]
thermostatic effects; properties that moderate changes in temp. Affect earth’s climate
precipitation, rain, snow, hail. Relase latent heat of condensation
sun eng->ocean->evap->high atoms->condense to clouds->precipitation
HEAT REMOVED FROM LOW LAT AND DEPOS IN HIGH LAT. PRECIP IN HIGH
LAT, EVAP IN LOW LAT
ice forming in high lat, moderates
water prevents vast climate differences
land day/night temp differences greater than ocean day/night differences. DUE TO HIGH
HEAT CAP OF WATER
marine effect; locations that experience moderating influence of ocean; coastlines, islands
continental effect; areas less affected by ocean have greater temp variations daily and
yearly
1g/cm3=water density
DENSITY INCREASES AS TEMP DECREASES
b/c molecules lose eng and slow, so same number of molecules occupy less space
thermal contraction; shrinkage caused by cold temps
-water density- increase to 4 deg C, then it decreases
ice floats- less dense than liquid
4 deg C=39 deg F
ice crystals; form below 4 deg C; bulky, 6-sided, open
water freezes, increases volume by 9%
increase pressure/add dissolved subs=decrease temp of max density for freshwater b/c ice
crystal formation is inhibited
-to produce ice crystals in freshwater, more energy must be removed.
SO! DISSOLVED SUB DECREASE FREEZING PT OF WATER
[lecture]
ophiolite;oceanic crust on land
methane hydr req high pressure, cool temp
dead critter release methane that is trapped in water molecules
physical property; intensive [not depend on size of sample] extensive [depends on how
much of soething there is] Observed/measured with out changing chem. composition
chem. prop; chem. processes
major dissolved constituents of ocean in same proportion regardless of total salinity
salt water more conductive than sea water
3.5% avg. sea salinity. 35%o.
Baltic= 1% [brackish]
Red=4.2% [hypersaline]
Dead=33%
tap=.8% less
ocean is 96.5% pure
ocean salinity highest at 25 degrees N/S lat
density highest at 20-25 deg lat
Chloride, Sodium, Sulfate, Magnesium, Calcium, Potassium, other
pH pure water=7
pH sea water=8.1[slight alkaline]
1%=parts per hundred
1%o=parts per thousand
goiters=insufficient iodine diet
principal of constant proportions; major salinity components occur everywhere in the
ocean in exact same proportion, ind of salin. William Dittmar
Chlorinity; weight of the chloride ion in water sample
19.2% avg chlorinity of ocean
ampulses; contains a measured amount of seawater used as a standard to calibrate
equipment. sent all over the world
salinometer; measures salinity [measures seawater electrical conductivity] Accurate
dissolved subs raise boiling point
1872 HMS Challenger=oceanography
brackish; low salinity due to mix of fresh and seawater
hypersaline; high salinity due to high evap and limited open circulation
Oregon low salin
TDS; total siddolved solids
runoff; stream discharge
precipitation, runoff, melting icebergs, melting sea ice [all decrease salin]
sea ice formed slow and old are mostly fresh water.
icebergs= fresh water
evap, sea ice formation [all increase salin]
hydrologic cycle; cycle of water to land, to ocean, from land, from ocean
fluxes;
ocean-atmos
atmos-ocean
atmos-cont
cont-atmos
cont-ocean
salinity/temp control density of water
temp moreso
salinity moreso only in polar areas high lats
S hemis salin high during N hemis winter
salinity varies in upper ocean 300m. deep ocean salin not varied
cold water in arctic sinks deep down, creates deep ocean currents
salinity increases; river flow, atmso, biological interactions
decreases; salt spray, chem. reac, biological interact, adsorption, evaporation
ions w/ long res time abundant in ocean
more abundant elements in oceans have longer res times, removed slowly
-helps describe the cycling of chem. species [nutrients] rapidly b/w bio pool and
dissolved pool
acid release H+
base release OHpH below 4.5 all fish die
ocean is layered by density
salinity lower in polar regions because of precip and runoff
salinity at surface varies with lat, not deep ocean
high lat low surface salin
density increase with temp decrease
density of poles affected mostly by salinity, because of uniform yearly temp
ocean has a “whispering” gallery
put hydrophones in certain continental shelf place, hear and ident a ship from
across the world.
pycno/thermo-cline only present in low lats. High lats, more uniform
ocean layering
-mixed surface; surface-300m
-upper waters; 300m-1000m
-deep waters; 1000m cold
carbonite ions; most abundant in streams, least in ocean [due to res time]
chloide ions; not so much in streams, but abundant in ocean [due to res time]
3.3b metric tons of salt spray leave the ocean each year.
entire vol of ocean recycled by hydrothermal circulation
sys finishes every 3m yrs
adsorption; ions removed from sea [physical attachment]
buffering; process by which carbonate is involved in keeping seawater neutral
dead organisms are antacids for deep ocean.
salinity low at high lat, highest at cancer and Capricorn, dips at eq.
at high lat sea ice formation/melting not a factor
cancer/Capri are tropical continental and maritime deserts
halocline; layer of rapidly changing salinity
high lat; salin increases with depth
low lat; salin decreases with depth
seawater density is 2-3% greater than pure water.
temp inc, dense dec
salin inc, dense inc
press inc, dense inc
only temp and salin affect surface density
deep ocean water is only 5% denser than surface water.
pycnocline; rapidly changing density
thermocline; rapidly changing temperature
thermoclines can develop in pools, ponds, and lakes also
pycno/thermo not develop much in high lats
isothermal/isopycnal; high lat waters
Ferdinand Magellan made first circumnavigation of earth
subvids of geo time once based on available evidence
lithosphere contains mantle and crust
continental crust rock is slight light
continental crust that is thicker, hotter, rises further out of ocean
lithosphere heated by asthenosphere will rise
most primitive life did not need sunlight
faster spreading, broader mountain range
slow spread equals steep, rigid terrain
earthquakes best describe plate boundaries
abyssal hill avg 200m, less than 1000m, above that, it is a seamount
fracture zones are not transform plate boundaries
continental rise=steep b/w shelf and slope
Aleutian islands due to volcanic activity
well developed shelves along active margins
shelfs relates to sea lvl and erosion
all bathymetry require time at sea
ocean surface height depends on bottom contours
satellites have not mapped entire ocean
there are large areas of ocean floor almost unexplored
hypso curve allows to tell how much water in ocean
maj of ocean floor below 4km deep
maj land below 1km high
can determine % planet covered by ocean
avg depth ocean 4X avgs height land
well developed continental rise; passive margin w/ rivers draining
margin w/ wide shelf, gentle slope
calcareous ooze is warm
as temp dec 20-5 deg C, dense inc
4 deg C dense peaks, then declines
H2O dense greatest at 4 deg C
latent heat can transfer energy from one place to another
evap 585
vap 540
increased salin results in LOWER temp req to freeze
high temp areas more likely to have lower density
COPYRIGHT 2007 BY LITERAL, INC.