Give an example
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| centimeters per year, so you must convert kilometers to cm and millions of years (m.y.) to years.
1 km = 100,000 cm; 1 million years (1 m.y.) = 1,000,000 years In the example above, the plate velocity is then: 250 km/3 m.y. = 25000000 cm / 3000000 years = 8.3 cm/ year Relative velocities are usually reported as a graph, so many measurements are taken. By reading the coordinates of the line, we can get the relative velocity (see the Lecture Notes on Plate Tectonics for full details). 7. The graph below shows the relative velocities of 2 mid ocean ridges, the Mid Atlantic Ridge at Iceland, and the East Pacific Rise. Using the method described in the Lecture Notes on Plate Tectonics, determine the velocity of each ridge in centimeters per year (cm/yr) 
Plate Velocity for Mid Atlantic Ridge at Iceland =_____________________ cm/yr Plate Velocity for East Pacific Rise = _____________ cm/yr Absolute Plate Velocities use a fixed reference point. A good way to determine absolute velocities is using hotspot data from a fixed hotspot, like the Hawaiian hotspot. Since the active volcano at Kilauea is currently over the hotspot, it is 0 years old. Use the map scale in the lower left corner and determine the plate velocity in cm/yr from Kilauea to Kauai (use a straight line distance). Remember 1 m.y. is 1,000,000 years, so if the age has a decimal, that counts as a place value! For example, 2.3 m.y = 2,300,000 years 
8. distance from Kilauea to Kauai = ______________km = ____________________cm age = _____________________years plate velocity of the Pacific plate over the Hawaiian hotspot = _______________ cm/yr 9. The 4 major tectonic features in western North America we see today are the San Andreas Fault, the Cascades, the Basin and Range Province, and the Rio Grande Rift. Name the type of stress that is responsible for each of these tectonic features. San Andreas : Rio Grande Rift : Basin and Range Province: Cascades: 10. If the Rio Grande Rift continues, what could this area look like in 20 – 30 million years? Name a present day example of this situation. 11. Label the letters A – G on the sketch below (continental crust, oceanic crust, asthenosphere, lithosphere, Moho, trench, volcanic arc) 
A = B = C = D = E = F = G = EXTRA CREDIT: For up to 4 points extra credit on Lab Exam 2, go to the following website EXPLORING THE BASIN AND RANGE to answer questions 12: http://ds.iris.edu/aed2/index.phtml?code=BASIN
How many square km does the Basin and Range cover? Approximately how many mountain ranges are in the Basin and Range? Approximately what is the maximum uplift between the top of these mountains and the down dropped valley? What 3 metals (barite is not a metal) are mined in the Basin and Range? Why are there so many mines in this region?
Why is the Basin and Range crust thin? Why is the Basin and Range Province at a high elevation?
How much are the Basin and Range mountains rising each year? How much is the Basin and Range Province extending each year?
Look at the map with arrows showing plate velocity and movement. In general, which direction is Nevada (NV) moving? In general, which direction is Oregon (OR) moving? Which state on this map has the fastest plate motion (shown by the longest arrows)?  Download 1.41 Mb. Share with your friends:
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