Reference no: EM133207187 , Length: Word count: 3 Pages

1. What is the name of the plate on which the United States resides?

2. Does this plate consist of continental lithosphere? Oceanic lithosphere? Or both?

3. Where does the lithosphere of the Atlantic Ocean form?

4. What kind of plate boundary occurs along the west coast of South America?

5. Is the west coast of Africa a plate boundary?

6. Look at the map of South America and Africa in the lab, how well do these continents appear to fit together? What are the problem areas, if any?

7. Are the current shorelines of South America and Africa accurate representations of these continents when they were first rifted apart? What factors other than rifting and sea floor spreading could have modified these shorelines?

8. Look at these continents again, do the tan/brown edges of the continents OR the light blue continental shelves fit together more accurately?

9. Based on your answer to question 8 above, where is the true edge of a continent?

10. What is the white arrow in the top center of the figure above pointing to?

11. What is occurring in this region?

12. Using figures in the lab, how does the volcanic and earthquake activity on the west coast of North America compare?

13. Examine the chain of volcanoes and line of earthquakes in the middle of the Atlantic Ocean in figures. What do you believe is causing these events?

14. Do the positive and negative magnetic stripes (anomalies) preserved in the oceanic crust have a distinct pattern or are they oriented randomly? Does seafloor spreading explain these orientations? If so, explain. 

15. Using your knowledge on seafloor spreading, why do you think some magnetic stripes are wider than others?

16. What does this progressive chain of volcanic centers indicate about the possible origin of the active volcanism at Yellowstone?

17. Based on the map, what was the average speed and direction of North American Plate motion at Yellowstone relative to the hotspot since 13.8 million years ago? Add an arrow (vector) and rate label to the map to show this movement.

18. Using the lab, what is the average speed at which BNA drifted away from the ridge at A during the past 67.7 million years expressed in cm/yr.?

19. Using the lab, what is average speed that BAF drifted from A?

20. Based on your answers above, which plate moved faster relative to the ridge over the past 67.7 million years, if either?