Download GEO115 - Ocean Bottom

Geology 115 – Ocean Bottom
Name: ________________________________________________________
Wilson Cycles. Most geologists believe that the Earth’s ocean basins open and close
over a periods of several hundred million years. Each of these periods is called what?
Draw the Wilson Cycle. Label the seven major phases of the cycle.
The bedrock of Gorham started as a stable craton. The craton was possibly the
Earth’s 1st continent. The name of the craton was ___________________
Rodina split apart. The early rifting must have been in the form of a __________
valley.
What were the two biggest continents formed when Rodina split?
What was the name of the ocean that formed between Gondwana and Laurentia?
The two continents started to drift back together. What formed on one or both sides
of the Iapetus Ocean?
What formed in the final stage of the Iapetus Ocean?
What’s an orogeny?
What mountain range formed with the closure of the Iapetus Ocean?
What remnant is left of the Iapetus Ocean?
About 150 million years after the Iapetus Ocean closed a new Wilson Cycle started.
What is the name of the new ocean related to the new Wilson Cycle?
What stage of the Wilson Cycle is the Atlantic Ocean in now?
The Ocean Floor. Draw a cross section of the ocean floor. Include and label the midocean ridge, abyssal plain, ocean trench, continental slope, continental shelf,
seamounts, and guyots.
Blue Planet – The Deep (38:30 to end)
http://www.amazon.com/gp/product/B003RZN6VK/ref=avod_yvl_watch_now
Mid-Ocean Ridges. In the middle of an ocean basin is a _____-________________
____________________. This is sometimes referred to as the mid-ocean rift.
Mid-ocean ridges are always at divergent boundaries. What is a divergent boundary?
Draw and label a diagram of a mid-ocean ridge. Include lithosphere, asthenosphere,
magma, crust, and ocean water.
Describe what happens at a mid-ocean ridge.
Reading Segment – Page 405
All of the Earth’s mid-ocean ridges are connected. What is the total length of the
whole interconnected web?
About how wide are the ridges?
Mid-ocean ridges start as rift valleys. What is a rift valley? (page 258)
Continental Margin
Continental Shelf. In some places the ocean bottom rises gently up the adjacent
continent.
What is the abyssal plain? (page 404)
What is the continental slope? (page 403)
What is the continental shelf? (page 402)
Subduction Zone. In other places the ocean bottom dives under the adjacent
continent. Draw a diagram of a subduction zone. Include ocean plate, continental
plate, asthenosphere, ocean trench, magma, and composite volcanic mountain range.
What happens at a subduction zone?
Ocean trenches are always a part of subduction zones. What is the deepest ocean
trench and where is it located?
Features Of The Ocean Floor.
What is a seamount? (page 404)
What is a guyot?
Atolls. What is an atoll? (page 406)
How do atolls start?
What structure forms around the sides of the extinct volcano?
What makes the reefs?
What happens to the volcano?
After the volcano is gone what is left?
What is a lagoon?