Download chapter 5 section 1

Bell Ringer
• For what reasons do people study the ocean
floor?
Exploring the Ocean
• Since ancient times
people have studied the
ocean such as waters
and ocean floor
• It provides food and
services, and serves as a
route for trade and
travel
Sonar
• Stands for Sound
Navigation and Ranging
• Is a system that uses
sound waves to
calculate the distance to
an object
Ocean Floor Makeup
• Ocean floor is made up of continental shelf,
continental slope, abyssal plain, and mid
ocean ridge
Continental shelf
• Is gently sloping, shallow area of the ocean
floor that extends outward from the edge of a
continent
• Depth of 130 meters and gets steeper
Continental Slope
• The steep edge of the continental shelf
Abyssal Plain
• Broad area
covered with
thick layers of
mud and silt
Mid Ocean Ridge
• Is a continuous range of
mountains that winds
around Earth, much as
the line of stitches
winds around a
baseball.
• Has 2 parallel chains of
mountains separated by
valley and trenches
Trench
• Is a steep sided canon in the ocean floor
• Some are so deep you cannot see the bottom
Plates
• Pieces of earths crust along with parts of the upper
mantle are called plates.
• This is what shaped the dramatic features of the ocean
Seafloor Spreading
• Mid ocean ridge is along
boundaries of plates that are
moving apart or diverging
• Magma squeezes up through
cracks
• Magma hardens
• And adds a new floor on the
ocean
• Seafloor spreading is what
produced our ocean floor