1. The Ocean Floor Why is it important to study the sea floor?
How did we find out about the ocean floor?
How did we learn about things like rift valleys, trenches, and hydrothermal vents?
How is the sea floor being explored today?

2. to further our understanding of the seafloor and the natural (or human) factors that shape it
assist in the navigation of ships
Even the sophisticated guidance systems on submarines, airplanes and intercontinental missiles require an understanding of the shape of the Earth in order to travel an accurate course.
Global shipping and communications industries depend on this information for the safe, speedy exchange of goods, people and information.
Why?
environmental assessments
solving the mysteries of the earth's formation.
determine fish habitats
locate minerals

3. SONAR-
SOund NAvigation and Ranging
As the ship moves across the sea surface, a sound is transmitted every few seconds with each trans-mission resulting in an echo from the seafloor.

4. Using multi-beam sonars, oceanographers can "illuminate" a swath of the seafloor many miles wide. 
With multi-beam mapping technique, shown here, thousands of measurements of the water depth are collected every few seconds or every time the ship travels 25 meters or so forward, over ten's of thousands of square kilometers (or miles).

6. Using Satellites to Map the Sea Floor
This map of the seafloor was produced by a technique called satellite altimetry where satellites use radar to measure the distance to the sea surface. False coloring shows different depths.

7. What does the shape of the sea surface tell us about the seafloor?
Electromagnetic energy (radar), is transmitted from a sensor on the satellite, travels to the ocean surface and bounces back to the satellite.
What does the shape of the sea surface tell us about the seafloor?
The Earth's gravity field piles up water over top a seamount causing the sea surface to mimic the shape of the seafloor,
In general, the sea surface bows upward 1 meter for every rise in the seafloor of 1000 meters (a ratio of 1 to 1000). 

8. F 1 2
Two major regions of sea floor: Continental Margin (1) and Deep-Ocean Basin (2)
Extending out from a continent's edge and lying between the shoreline and the continental slope (A) is a gently sloping, shallow area called the continental shelf (F). 
The continental slope (A), a steep drop, marks the true edge of the continent, where the rock that makes up the continent stops and the rock of the ocean floor begins. 
Beyond this slope is the abyssal plain (C), a smooth and nearly flat area of the ocean floor. 
A trench G) runs parallel to a chain of volcanic islands or continental mountains.

9. In some places, deep, steep-sided canyons called trenches (G) cut into the abyssal plain. 
A continuous range of mountains called the mid-ocean ridge (D) winds around Earth. 
There are mountains on the abyssal plain, too.  Some reach above the ocean surface to form volcanic islands (E). 
Others, called seamounts (B), are completely under water.

10. The sea floor below the break is the continental slope
The sea floor below the break is the continental slope. Below the slope is the continental rise, which finally merges into the deep ocean floor, the abyssal plain. The continental shelf and the slope are part of the continental margin.

12. Piloted Submersibles ALVIN
Alvin has made more than 3,700 dives for a wide variety of scientific endeavors. The submersible’s most famous exploits include locating a hydrogen bomb accidentally dropped into the Mediterranean Sea in 1966, exploring deep-sea hydrothermal vents discovered some two decades ago, and surveying the sunken ocean liner Titanic.

13. The Deep Flight 1 is a radical new submarine designed for underwater filming and fast descent in the underwater environment. The craft does not depend upon ballast to adjust its depth. The use of stubby inverted wings pulls the craft down to dive, so it 'flies' underwater like a conventional plane in air

14. Jason/Medea is a remotely operated vehicle (ROV) system designed for scientific investigation of the deep ocean and seafloor. Jason explores the sea floor while tethered to Medea by a 35 meter cable.
Together they offer wide area survey capabilities with Jason as a precision multi-sensory imaging and sampling platform. Both Medea and Jason are designed to operate to a maximum depth of 6,500 meters (21,385 feet), are transportable, and can be operated from a variety of vessels.
Robotic Submersibles
The Jason/Medea operation requires six people per watch section (3 DSL, 3 science) to maintain round-the-clock operation. Watch sections are generally four hours on, eight hours off.