Ocean BottomOcean Bottom

The Water PlanetThe Water Planet

Global ocean is consists of all the oceans Global ocean is consists of all the oceans on the Earthon the Earth

A sea is a smaller body of ocean water A sea is a smaller body of ocean water that may be surrounded by landthat may be surrounded by land

OceanographyOceanographyOceanography began when Matthew Maury Oceanography began when Matthew Maury aboard the HMS Challenger explored the aboard the HMS Challenger explored the oceans with limited technology from 1872-oceans with limited technology from 1872-1876.1876.

Today with modern technology ships like the Today with modern technology ships like the JOIDES Resolution and the CHIKYU, both drill JOIDES Resolution and the CHIKYU, both drill the ocean bottom finding out more about the the ocean bottom finding out more about the workings of plate tectonics and workings of plate tectonics and

sediment of the ocean.sediment of the ocean.

SonarSonarSound Navigation and Ranging is a system that Sound Navigation and Ranging is a system that uses sound to determine the depth and features uses sound to determine the depth and features of the ocean bottom. Side scan radar is used to of the ocean bottom. Side scan radar is used to map the bottom of the oceanmap the bottom of the ocean

Under water Submersibles are used to explore Under water Submersibles are used to explore the depth, some with robots to collect samples.the depth, some with robots to collect samples.

Continental slopeContinental slope is at the edge of is at the edge of the continental shelf where the the continental shelf where the sea floor may plunge steeply 4-5 sea floor may plunge steeply 4-5 kilometerskilometers

Marks the boundary between the Marks the boundary between the continental crust and the oceanic continental crust and the oceanic crustcrust

Continental riseContinental rise is the area between the is the area between the continental slope and the ocean floorcontinental slope and the ocean floor

It is made of sediments that wash down It is made of sediments that wash down from the continental shelffrom the continental shelf

Turbidity currentTurbidity current carry large amounts of carry large amounts of these sediments in masses of moving these sediments in masses of moving water, it is like an underwater avalanchewater, it is like an underwater avalanche

Submarine canyons are deep Submarine canyons are deep V shaped valleys cut through V shaped valleys cut through the continental shelf and the continental shelf and slopeslope

Features of the Ocean FloorFeatures of the Ocean Floor

Abyssal PlainAbyssal PlainLarge flat areas on the bottom of the oceanLarge flat areas on the bottom of the ocean

Atlantic and Indian oceans have largest Atlantic and Indian oceans have largest abyssal plains because almost all the worlds abyssal plains because almost all the worlds major rivers flow into them producing a large major rivers flow into them producing a large amount of sediment deposits in the plainsamount of sediment deposits in the plains

Seamounts and GuyotsSeamounts and GuyotsSeamounts are underwater volcanic mountainsSeamounts are underwater volcanic mountains

They have steep sides and narrow summits They have steep sides and narrow summits and rise more than 1000 meters above the sea and rise more than 1000 meters above the sea floorfloor

When seamounts rise above the surface of the When seamounts rise above the surface of the ocean they become islandsocean they become islands

Guyots are seamounts that do not rise to a Guyots are seamounts that do not rise to a peak or have eroded topspeak or have eroded tops

Mid-ocean RidgesMid-ocean RidgesLargest mountain ranges on the Largest mountain ranges on the EarthEarthThese are formed where the plates These are formed where the plates are pulling apartare pulling apartRift valleys run along the middle of Rift valleys run along the middle of the mid-ocean ridgesthe mid-ocean ridges

TrenchesTrenchesThe deepest part of the ocean found along edges The deepest part of the ocean found along edges of sea floorof sea floorLong narrow crevices that can be 11,000 meters Long narrow crevices that can be 11,000 meters deepdeepDeepest trench is the Mariana Trench in the Deepest trench is the Mariana Trench in the Pacific Ocean that is more than 11,000 meters Pacific Ocean that is more than 11,000 meters deepdeep

Hydrothermal VentsHydrothermal VentsOpenings into the mantle of the Earth Openings into the mantle of the Earth where sea water seeps down and where sea water seeps down and returns to the oceanreturns to the ocean

ReefsReefs

Reefs are large masses and ridges of Reefs are large masses and ridges of limestone rocks produced by the shells of limestone rocks produced by the shells of animalsanimals

There are three types of coral reefs: There are three types of coral reefs: fringing fringing reefs reefs touch the shoreline of a volcanic islandtouch the shoreline of a volcanic island

Coral Reefs (cont)Coral Reefs (cont)

Barrier reefs Barrier reefs that are separated from that are separated from the shore by an area of shallow water the shore by an area of shallow water called a lagooncalled a lagoon

Coral Reefs (cont)Coral Reefs (cont)

And an And an atollatoll that is a ring of coral reef that is a ring of coral reef that surrounded an island that has been that surrounded an island that has been worn away or sunkworn away or sunk

Properties of Ocean WaterProperties of Ocean WaterOcean water is a Ocean water is a

mixture of gases and mixture of gases and solids dissolved in solids dissolved in pure waterpure water

Oceanographers Oceanographers believe that ocean believe that ocean water contains all of water contains all of the natural elements the natural elements found on Earthfound on Earth

All but 5 have been All but 5 have been foundfound

Gases in Ocean WaterGases in Ocean WaterNitrogen, carbon dioxide Nitrogen, carbon dioxide

(60 times more than in (60 times more than in atmosphere), and oxygen atmosphere), and oxygen are the most abundant are the most abundant gasses found in ocean gasses found in ocean water cold water has more water cold water has more dissolved gases in itdissolved gases in it

Oxygen and carbon Oxygen and carbon dioxide are essential for dioxide are essential for plant growthplant growth

There is more gas found at There is more gas found at the surface of the water the surface of the water where plant growth occurswhere plant growth occurs

Gases and Ocean FactsGases and Ocean FactsColder temperatures hold more gas.Colder temperatures hold more gas.

The ocean contains 60 times more The ocean contains 60 times more carbon that the atmosphere does.carbon that the atmosphere does.

The oceans are the most important The oceans are the most important factor in regulating climatefactor in regulating climate..

Salts in Ocean WaterSalts in Ocean Water

SalinitySalinity is the amount of is the amount of dissolved salts in ocean dissolved salts in ocean waterwater

Sodium Chloride is the Sodium Chloride is the most common saltmost common salt

Average salinity of the Average salinity of the ocean is 35 o/ooocean is 35 o/oo

Salt comes from volcanic Salt comes from volcanic activity, erosion of the land, activity, erosion of the land, and wave erosion of and wave erosion of beaches beaches

Sea saltsParts per Thousand

chloride 19.3 o/oo

sodium 10.7 o/oo

sulfate 2.7 o/oo

magnesium 1.3 o/oo

calcium 0.4 o/oo

potassium 0.4 o/oo

bicarbonate 0.15 o/oo

bromide 0.07 o/oo

other 0.06 o/oo

Total Salinity

35.08 o/oo

SalinitySalinitySalinity can be greater or Salinity can be greater or

less than the average of less than the average of 35 o/oo35 o/oo

Lower salinity where Lower salinity where freshwater rivers enter the freshwater rivers enter the oceanocean

Salinity is higher where Salinity is higher where there is greater there is greater evaporation and in polar evaporation and in polar regions where only fresh regions where only fresh water freezeswater freezes

Animals using certain Animals using certain salts to build their shells salts to build their shells can lower salinitycan lower salinity

Deep Cold WaterDeep Cold Water

Cold water holds more gas Cold water holds more gas than warm waterthan warm water

When the colder denser When the colder denser water sinks to the bottom it water sinks to the bottom it carries oxygen rich water carries oxygen rich water that aids in the survival of that aids in the survival of deep water species deep water species

Temperature of Ocean WaterTemperature of Ocean WaterThe sun is the major source The sun is the major source

of heat for the oceanof heat for the ocean

Surface zoneSurface zone -100-300 -100-300 meters deep, temperature meters deep, temperature fairly constant, waves and fairly constant, waves and surface winds mix the water surface winds mix the water and transfer the heat and transfer the heat downwarddownward

Temperatures (cont)Temperatures (cont)Thermocline- found Thermocline- found

directly under the directly under the surface zone, surface zone, temperature drops temperature drops rapidly, less dense rapidly, less dense warm water floats on warm water floats on top of the more dense top of the more dense cold watercold water

Temperature (cont)Temperature (cont)

Deep zone- has extremely Deep zone- has extremely cold water, extends from the cold water, extends from the thermocline to depths of thermocline to depths of 4000 meters or more, 4000 meters or more, temperature decreases only temperature decreases only slightlyslightly

Temperature below 1500 Temperature below 1500 meters is only 4°meters is only 4°

TemperatureTemperatureThe three ocean zones are not The three ocean zones are not

found in the Arctic or Antarcticfound in the Arctic or Antarctic

The surface temperatures are The surface temperatures are always very coldalways very cold

Density and ColorDensity and ColorThe density of the The density of the water gets greater water gets greater the deeper and the deeper and colder the water is.colder the water is.

Blue wavelengths of Blue wavelengths of light are reflectedlight are reflected

Phytoplankton can Phytoplankton can affect the color of the affect the color of the ocean can show the ocean can show the health of the oceanhealth of the ocean

UpwellingUpwellingThe movement of deep, cold, and nutrient The movement of deep, cold, and nutrient rich water to the surface to support life.rich water to the surface to support life.

Ocean Life ZonesOcean Life ZonesPlant and animal life in the ocean is Plant and animal life in the ocean is

affect by three factors: amount of affect by three factors: amount of sunlight, temperature, and pressuresunlight, temperature, and pressure

Plants and animals can be classified into Plants and animals can be classified into three major groups according to their three major groups according to their habitats of the water in which they livehabitats of the water in which they live

PlanktonPlankton

Largest group of animals and plants Largest group of animals and plants that float at or near the surfacethat float at or near the surface

These get the most sunlightThese get the most sunlight

Found at depths of 1 to 200 meters Found at depths of 1 to 200 meters deepdeep

Very small organisms (plankton that Very small organisms (plankton that whales eat)whales eat)

NektonNektonContains all forms of organisms Contains all forms of organisms

that swim aroundthat swim around

They can actively search for food, They can actively search for food, prey or predatorsprey or predators

These are found in all areas of the These are found in all areas of the oceanocean

BenthosBenthosOrganisms that live on Organisms that live on

the ocean floorthe ocean floor

Benthic plants live in Benthic plants live in shallow water so they shallow water so they can get the necessary can get the necessary sunlightsunlight

Oysters, crabs, Oysters, crabs, starfish are all benthicstarfish are all benthic

Some even live in the Some even live in the deepest parts of the deepest parts of the oceanocean

Ocean Environments (Zones)Ocean Environments (Zones)The The

classification of classification of the ocean into life the ocean into life zones is based zones is based on the conditions on the conditions of the ocean-of the ocean-conditions that conditions that vary widelyvary widely

Intertidal Zone (Benthic Zone)Intertidal Zone (Benthic Zone)The region that lies between low The region that lies between low

and high tideand high tide

Organisms must be able to live Organisms must be able to live without water some of the timewithout water some of the time

They must find someway to attach They must find someway to attach so they are not washed out when tide so they are not washed out when tide goes outgoes out

Includes anemones, crabs, Includes anemones, crabs, mussels, and plantsmussels, and plants

Neritic Zone (Pelagic Zone)Neritic Zone (Pelagic Zone)Extends from the low tide line to the edge of the Extends from the low tide line to the edge of the continental shelfcontinental shelfDepth of about 200 metersDepth of about 200 metersReceives plenty of sunshineReceives plenty of sunshinePressure is low and temperature is constantPressure is low and temperature is constantPlankton, nekton, and benthos plants and Plankton, nekton, and benthos plants and animals are found hereanimals are found hereRiches part of the sea: contains fish, clams, Riches part of the sea: contains fish, clams, snails, some smaller whales, and lobsterssnails, some smaller whales, and lobstersMuch of the seafood we eat is found here!Much of the seafood we eat is found here!

Open-Ocean ZonesOpen-Ocean Zones

Bathyal zoneBathyal zone begins at the continental begins at the continental slope and ends about 2000 metersslope and ends about 2000 metersSunlight cannot penetrate to the bottomSunlight cannot penetrate to the bottomSquid, octopus, and large whales are Squid, octopus, and large whales are found herefound hereAbyssal zoneAbyssal zone extends to over 6000 meters extends to over 6000 metersNo sunlight can penetrate, high pressure No sunlight can penetrate, high pressure and low temperaturesand low temperaturesMost animals are small and strange!Most animals are small and strange!