Exam 3

Question 1
15 / 15 pts
Describe how the “biological pump” in the oceans works, and what happens to the nutrients in this cycle. What brings the nutrients back to the surface again? What would happen if it shut off?

 
Question 2
15 / 15 pts
Describe the pattern of magnetic anomalies across a mid-ocean ridge. Describe how they form, and how they tell us that seafloor is spreading.

 
Question 3
12 / 15 pts
In the video “One Strange Rock: Gasp”, we saw a good example of a biogeochemical cycle. Describe how silica goes from the Sahara Desert in Africa to the Amazon, what it does there, and the rest of the steps of the cycle. Where does the silica finally end up, and what does it do?

 
Andes?
 
Question 4
15 / 15 pts
Describe the three different types of ACTIVE (CONVERGENT) MARGINS (NOT the three types of plate boundaries!), using the names given to them after typical mountain belts that exemplify them. Be sure to indicate whether each plate is continental or oceanic crust.

 
Question 5
15 / 15 pts
What is the CCD? How deep is it, and why is it so much deeper than expected from the actual depth of 1 km, where carbonate becomes undersaturated in seawater?

 
Question 6
15 / 15 pts
Describe how the paths of P and S waves through the earth and their shadow zones tell us about the earth’s interior. What does the S-wave shadow zone tell us about the outer core?

 
Question 7
10 / 10 pts
SHORT ANSWER ID: 2-3 sentences each
REDFIELD RATIO

 
Question 8
10 / 10 pts
CHONDRITIC METEORITE

Question 9
10 / 10 pts
NITROGEN FIXATION

 
Question 10
10 / 10 pts
RESIDENCE TIME

 
Question 11
10 / 10 pts
HOT SPOT

 
Question 12
10 / 10 pts
CORAL BLEACHING