-
the ocean floor is blanked with
organic, inorganic matter and non decomposed fossels
-
terrigenous
originated on land. quartz, clay and mud from weather contiental rocks
-
biogenous
remains of marine organims
-
hydrogenous
elements and minerals preciptating from seawater"hardwater rings"
-
cosmogenous
sea craters debris from space
-
terrigenous sediments
- grey and red material
- most abudent materal in volume
- most are deep sea clay
-
how are terrigenous sediments transported
by wind that blows over africa and sends it over the atlantic ocean to the caribean, bahamas and florida
-
how are terrigenous sediments transported #2
- valcano ash blowing out of the atmosphere
- glacially trasport "sand and mud" from an iceburg drifting
-
what colors are iceburgs
brown and black
-
what is a green iceburg
algae
-
abyssal plains accumulation
.5 to 1cm per 10,000 years
-
contiental shelves
1 to 4 cm per 100 years
-
deltas and estuorres
2 to 3 cm per day
-
terrigenous sediments are much less from
distance from the shore increases
-
biogenous sediments
- mainly made of tiny micro shells
- form form the remaing living orgainsms
-
biogenous sediments are most common
by volume and they cover more of the ocan floor
-
2 main sediments
calareous and silicecus
-
calcareous ooze
- most in the sea
- layers of muddy, calcium carbonate (CaCO3) bearing softrock sediment on the seafloor
-
siliceous ooze
made of quartz and siliceous skeletal remains of organisms
-
what are common sources of biogenous sediment on the continental shelf
coral clams oysters etc
-
-
macifica
whats in the water calcium
-
-
hydrogenous sediments
forms from material that precipitate directly out of sea water.
-
Types of hydrofenous sedments
- carbonates (calcite)
- phosphates(deep ocean floor, oil, birdpoop)
- mangnise nodules
- salt
-
polymatallic nodules
htdrogenous sediment usually found in deep ocean areas free from other sediments, common in the pacific ocean.
-
cosmogenous sediments
formed from debris from space (mostly micrometeteorites) 20,000 tons per year silicate and iron/nickle materal.
-
microtektites
form from major impacts, looks like glass beads
-
chesapeak bay is covered by
sediments
-
calcareous ooze distribution
- produced in large amounts but limited in where it accumlates
- disolves in cold acidic water, (acidic water) typically in deep marine area
-
the carbonare compensation depth
- depth below which calcite accumulation is excedeed by calcite dissolution
- deeper in the atlantic then in the pacific
-
calcite skeletons desolve below the
CCD so calcareous ooze dont accumulate in the deep ocean regions , abyssal plains, trenches
-
siliceous ooze distribution
produced in less amounts then calareous ooze
-
distribution does
not disolve easy in cold acidic water
-
siliceous ooze found in
deeper reagons of the polar ocean
-
siliceous ooze percentage cover by ocean floor
-
marine sediment economic value
phosphates, managenese, nodules, gas hydrates( natural gas locked in ice)
-
climate regulation
the ocean is a major part of earths carbon doixide cycle, sediments contain large amounts of it
-
scientfic value
find clues to ancient oceanorgraphy and atmospheric conditions
-
properties of ocean water
- absorbes and releases large amout of heat
- absorbes solar radation( tropics) and retains it long enough for transfer into polar reagons.
-
large bodies of water change temp
very slowly, stablizing global climate and influencing huricans.
-
pressure increase with depth
1 atmosphere for every 10 meters
-
avg shelf pressure
13 atmospheres
-
avg abyssal plain pressure
500 atmospheres
-
deepest trench pressure
1100 atmosphere
-
max depth of a diver
130 ft
-
tendency of heat in the cental atlantic and pacific ocean to be shifted
west
-
wind can
raise or lower ocean temp
-
sunlight is absorbed
quickley in clear water
-
at 1 meter
60% light absorbed
-
10 meters
80% light is absorbed
-
100 meters
93% light is absorbed
-
1 kilometer
100% light is absorbed
-
what type of light is absorbed first
infered light (heat)
-
two other absorbed quick
red light then ultaviolate
-
what is not affected the same
color
-
what deep ocean color goes depest
bluish tint (blue light)
-
what type of sound quickly absorbed
High Frequency
-
what type of much farther and east broadcast
Low Frequency
-
shound travels how many times faster in water then air
5 times
-
how is speed influenced
water temp and water pressure
-
the zone of min sound velocity but greatest efficency slower but more effective
SOFAR Layer
-
what depth for min sound velocity effective sound
1000m
-
used to locate shiprecks and map the landscape of the ocean floor and makes good pictures
side-scan sonar
-
ocean water within avg salt content will freeze at
28F
-
areas of greater salt content the water will
freeze at a lower temp
-
dead sea 9 times salter takes
-18F to freeze
-
when the water freezes what is not included
salt
-
most ice water is
fresh water
-
ocean water freezes at 28 but melt at what
32F
-
frozen seawater allows to be larger and drift
closter to the equater
-
two types of ice
sea ice and icebergs
-
what is sea ice
- forms from frozen sea water
- thin 5 to 30 ft
- brittle
- krill feed on algae beneath the ice
- forms seasonal floes or ice fields
-
ice bergs
- form from glacial ice
- form on land from compacted snow
- more common on costal water
- massive stronger and dence
- not all white, if green, it turned over and alge on it
-
who tracks ice burgs since the titanic sank
international ice patrol
-
pinnacle ice bergs
- from small glaciers
- most common in northern hemisphere (altantic ocean)
- carried long distances by current
-
tabular iceburgs
- form from massive contiental glaciers
- most common in souther hemespher
- stay close to the antartic coast
-
the IIP has expirental demolition of icebergs by
- areal bombing
- naval guns
- thermite charges
- napalm
-
oceans contain trace amounts of
disolved gases
-
salinity
the total quanitiy of disolved inorganic material in the water
-
the avg salinity of the ocean is
3.5% or 35 ppt( part per thousand)
-
virtually everthing is disolved in
seawater (this is part of the oceans 35ppt salinity) (nonliving)
-
what is the dominate salt
NaCL (table salt)
-
what can alter the oceans salinity
any process that adds or removes materals such as calcium iron and patassium
-
regional salinity may be lower because of
- heavy rain
- major rivers
- promixity to melting glaciers and or icebergs
-
reagonal salinity my be raised by
- higher evaporation rates
- isolation
-
salinity also varies on
depth season and latitiude
-
what type of storm can change salt levels
huricans
-
how is salt added to the ocean
rivers and undersea valcanoies
-
rivers transport
disolved materal genterated by chemical beakdown(weathering)
-
rivers add what
patasium iron calcium sofium and allumnum.
-
underwater valcanoes add salt
- seamounds
- midocean ridge
- hydrothermal vents
- add large large amounts of disolved materal
-
underwater valcanoes add
icon mangnes magnesium, sulfer phororus coper
-
the ocean water is relativley stable bc
its constanly removed at roughly the same rate it is beign added
-
salt is removed by the oceans by
- 1.evorapation( creates hydrogenous sediments in areas of high temp high evaporation)
- 2.adsorbition onto pelagic mud and clays (small electrical charges bind large amounts of salt to ocean sediments)
- 3. biologicactivity (the living organisms creat shells and skeletal materals.
-
how low is the materal removed
depends on the burrial of organisms after death.
-
what keeps ocean in balance with salt
marine life
-
most gases are
easily dissolved in sea water
-
atmospheric proportions
- 1 nitrogen (n2)
- 2 oxygen (o2)
- 3 carbon dioxide (co2)
- All shallow water
-
what cycles through air into ocean, exchange is best at upper level
carbon dioxide
Deep layer
-
gases in the sea water
- 1 nitrogen- from the atm, gas exchange
- 2 oxygen - from the atm, gas exchange
- 3 carbon dioxide- from the atm and volcanism
- 4 arson- atm and valcanism
- 5 neon- from undersea volcanism
- 6 helium- from undersea volcanism
-
the deep ocean comsumed by
- higher co2 (carbon dioxide)
- but oxygen higher at upper layers
-
carbon dioxide leads increase with depth
- 1 increase water pressure (water pressure can hold more disolved gases)
- 2 decrease plant activity (algey take out co2, as light levels fall co2 increase.(photothensis)
- 3 presence of animal life( respire co2 and consume o2 wiht no plants the co2 rises)
-
what plays a major part of the chemisty of the deep ocean
single cell organisms
-
ocean 3 layer structure
- the surface zone 2% of ocean water
- the pycnocline -18%
- the deep zone- 80 % most
-
these layer mightnot appear in
polar regions dure to colder temp and icecover
-
Surface zone
- minor part
- the upermost zone
- temp and salintart are constent
- connstant mixing due to wind waves and surface curents
- 1500ft max
-
for the ice it goes from ice to
deep zone
-
the western pacific , w atlantic mainly the gold and caribean and western indian ocean contain warmer water then the eastern counter parts bc
- surface curerents move warm ewuatoral water into these arreas and
- the earths rotation piles up the warm water
-
where is most of of ocean heat located
western pacific
-
what is the key temp for hurricans
80F
-
the central pacific and central atlantic and cnetal indian ocean contail more sallinitic water why
- isolation from the surrounding surface currents
- high evaporation rate and low rainfall
Deeper and colder you go
calcareous ooze
-
a transitional zone where density increase sharpley with increasing depth and sightly more dence
pycnocline
-
what animal can go from zone to zone
whales
-
how is the pycnocline created
the rapid decrease in temp with depth
-
the zone of rapidly changing temp
thermocline
-
pycnocline characterstics
the cold water sinks toward the bottom from the ice in polar reagons.
-
sudden change of salinity with depth
halocline 35ppm to 38 ppm
-
deep zone
- below the pycnochine
- depths below 1000m
- lil change in density wiht increasing depth
-
circulation in the deep ocean
- circulation from top to bottom
- density of sea water is the driving mechanism for deep water circulation
- density changes with temp and salinity change
-
cold water tends the sink beneath warmer water higher salinity water sinks below loner salinity water
thermohaline circulation
-
there are three types of deep water currents
-
antarctic bottom water
- the deepest,densest and coldest int the atlantic.
- drops from the top to the bottom from the antartic (oxygen from the top drops to bottom)
- forms at 60degrees south america and flows to the North.
-
how many years it make toake to cross the equator
600 to 700 years
-
north atlantic deep water
- forms in the artic ocean
- flows south in deep channels near iceland and greenland
- temp 33 to 36F
- water less dense then AABW.
- most of the water stays in the artic due to bottom top supply
-
antarctic indermidiate water
- a warmer mass of water
- forms souther latitudes
- found abouve AABW and NADW
- This is the middle
- it hits the mid ocean ridge and brings nutrients up
-
pressure gradient force
- the driving force of wind
- goes from high pressure to low pressure
-
coriolis effect
the wind curve to the right
-
high and low pressure blow
high out to the right and low in to the right
-
trade wind
blow from east to west, influences huricans
-
the prevailing westerlies
blow from west to east, influences tornatoes
-
polar easterlies
blow east to west
-
low pressure circulating earth equator, moves north in summer and storms can form along this line
the intertropical convergence zone (ITCZ)
-
warm salt water form
clouds so more rainfall and snow then other contiental interiors
-
reagons where cold ocean water near the coast
no clouds form bc low humidity so no rain ( Costal deserts)
-
land is warmer then the sea and land acts like a low pressure
onshore breeze ( wind water to land)
-
winds tends to go to
heat
-
warmer water then land. land is high pressure
onshore breeze ( wind from land to water)
-
are seasonal wind patterns
monsoons
-
large amounts of rain, india land warmer then the ocean
summer monsoon
-
indian land cools and wind from land to ocean, rainy seasons end
winter monsoon
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