 Fathom: Six feet down in depth. 1 fathom = 6 feet  Nautical mile: 6,076 feet across the ocean surface.

 Oceanography: The scientific study of the ocean using chemistry, biology, physics, geology and other sciences

US Naval officer who was the father of modern oceanography.

 The first large-scale ocean research project  Onboard lab to measure ocean depths, take water samples record temperatures and study currents.

Note the name of the chief Scientist in your notes Note the name of the chief Scientist in your notes

 Big advances in oceanography  Submarines  Surface ships- More accurate ocean charts  Sonar  Magnetic recorders

 Research vessels ◦ Deep-sea corers- JOIDES Resolution  Alvin: Mini-sub that has explored deep- sea trenches, vents and the Titanic  Argo: Robotic sled that has lights and cameras  Buoys: collect data

◦ Core sampling is used to look at seafloor sediments ◦ Cores can remain intact and easy to study layers ◦ Dredging- scooping up sediment to study

 Depth recorder sends out sound waves that travel to the ocean floor and return  The time is recorded and used to find distance  Intensity of reflected beam can determine sea floor composition and shape of objects.  D= S x t

 Echo sounding is a very slow method of mapping ocean floor  Satellites provide a better range and speed to mapping.  Satellites look for variations in surface elevations to make maps

Salinity-measure of the amount of dissolved salt contained in water

1. Average 35 parts salt dissolved per thousand parts water(35/1000) NaCl, MgCl and MgS most common salts 2. Salt sources could be from wave action, volcanic action or erosion of glaciers and rivers 3. About 85 elements found in the ocean 4. The amount of salt present determines density (high salinity-more dense)

5. Variations in Salinity ◦ Location ◦ How much fresh water is present (low where there is a lot) ◦ Rate of evaporation/ freezing- faster is higher salinity

 The same gases found in air are dissolved in ocean water  Nitrogen, oxygen, carbon dioxide  Ocean animals take in oxygen and give off carbon dioxide  Plants use carbon dioxide and release oxygen THIS YOU SHOULD ALREADY KNOW

 Surface (top)- Warmest layer and varies with location and season. Less dense  Thermocline (middle)- Area of rapid temperature change with depth. Warm and cold do not mix well here  Deep Water (bottom)- Coldest layer. Denser water. Polar water found in all water in all latitudes except for Mediterranean Sea. ***The polar regions of the world do not have these zones

If we look at the ocean, we see miles and miles of water. However, if we were to look under the water, we would see many features that are similar to those found on land. There are two major areas of the ocean.

a. Shoreline-where land and ocean meet b. Continental Shelf- Shallow depth. Flat. Many resources found here (oil & gas) c. Continental slope- Water depth increases. Land drops. Boundary between oceanic and continental crust d. Continental rise- Accumulation of sediment at the bottom of Continental slope.

 Large underwater valleys that have resulted from mudslides from the continent.  Some line up with rivers and some do not  Turbidity currents are also responsible for making the canyons.

 Active (earthquakes, volcanoes): West coast of U.S.  Passive: East Coast of the U.S.

a. Abyssal Plains: Flat areas of ocean floor; Larger in the Atlantic and Indian Ocean. The Pacific ocean has many deep cracks that trap sediments like mud, sand and ooze (remains of organisms) b. Ocean trench-long, narrow, steep-sided clefts or troughs (volcanic and earthquake activity) ◦ Mariana trench is deepest in world

d. Seamount- cone shaped mountain peaks. Lot in Pacific where volcanoes hot spots are **Guyots- Seamounts with tops sliced off by wave action and sinking of ocean crust. e. Volcanic Mountains-underwater volcanoes tall enough to reach the surface of the water

 Occur in tropical waters near the continental shelf  Coral reefs ◦ Masses/ridges of limestone rocks ◦ Contain the shells of animals  3 types  Fringe reefs (Y)-touch the shore of volcanic islands (letter C-already sinking)  Barrier reefs(Z)-separated from shore by a lagoon. Island (F) is eroding and sinking  Atoll (X)-surrounds a sunken island (X above)and forms a  A lagoon (A, E) is water surrounded or trapped by reefs