Transcript Exploring the Ocean

Science EQ: What does the ocean floor look like?
Do Now: 1-28
LG: Descr5ibe the composition, location, and
subsurface topography of the world’s oceans.
HW: Study for Brain Check on 13-1
*Q: What is the average salinity of the oceans?**
1. Take out 13-1 Directed
Reading
Today
~ Ocean Floor
power point w/notes
A: 1000g of water – 35 g salt
The Ocean Floor
Why is the ocean difficult to study?
>It is DEEP! 3.8 km; twice as deep as the Grand Canyon
> It is DARK and COLD! Only a few degrees above
freezing.
> It has extreme PRESSURE! Why??????????
So, how did we map it?
SONAR: Sound Navigation and Ranging
**Ships bounce sounds off the ocean floor and time
how long it takes them to return to the ship.
What did they find?
1.
2.
3.
4.
5.
6.
7.
8.
Continental Shelf
Continental Slope
Continental Rise
Abyssal Plains
Mid-Ocean Ridge
Rift Valleys
Seamounts
Ocean Trenches
1. Continental Shelf
 Looks like a flat shelf on
the edge of a continent
 Ranges from 10km-350km
wide
 Depth can reach 200 m.
 Home of many ocean
plants and animals
because sunlight reaches
the bottom.
2. Continental Slope
 Slope that reaches
from the edge of the
continental shelf to
the ocean bottom.
 Steeper than the
continental shelf.
 Depth is 200-4000
meters
3. Continental Rise
 The base of the continental slope
 Made of piles of sediment
Continental
Rise
4. Abyssal Plains
 Flat seafloor area at the bottom of the continental
slope
 4000-6000 meters deep
 Covered in decayed animal material
5. Mid-Ocean Ridge
 Underwater chain of
volcanic mountains
 Location of seafloor
spreading
 6. Rift valley is between
the ridges
Mid Ocean Ridge – Rift Valley
RIFT VALLEY
7. Seamounts
 Submerged volcanic material on the ocean floor. Some
may be active near the mid-ocean ridge
 Volcanic Islands: Seamounts that rise above the water
8. Ocean Trenches
 Mostly found in the Pacific Ocean.
 Deep valley on the seafloor where crust is returning to
the mantle.
1. ocean/ocean collision
2. ocean/continental collision
 Ex: Marianas Trench
deepest place in the Pacific Ocean
11km deep.
Mount Everest could fit inside it!
Name the features!
H
Here are the answers:
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A: Continental Slope
B: Seamounts
C: Abyssal Plain
D: Rift Valley
E: Volcanic Island
F: Continental Shelf
G: Trench
H: Continental Rise
I: Mid-Ocean Ridge