Page 84 - Laboratory Manual in Physical Geology

C. The map below shows the distribution of volcanic calderas (sub-circular depressions caused by repeated volcanic explosions
and the associated faulting, tilting, and collapse of the crust) in Wyoming, Idaho, and Nevada. Geologist, Mark Anders
mapped and dated these calderas. He also discovered that all of them are now inactive except for the one located directly over
the Yellowstone National Park region. The hot springs, geysers, and earthquakes at Yellowstone indicate that the site is still
volcanically active.

N
ellowstone
e
Y Y
Yellowstonellowstone Montana
National
National Parkark
National Park
P
0.6
1.3
Oregon Idaho 2.0
Yellowstone Faults
National Park 4.3
6.2
6.6
10.3 Faults
11

12.5
Wyoming
13.8
Idaho
Nevada Utah
0 100 200 km

1. Do you think that Yellowstone National Park could be located over a hot spot? Why?

2. Based on the map, what was the rate in centimeters per year (cm/yr) and direction of North American Plate motion at

Yellowstone since 10.3 Ma?

Add an arrow (vector) and rate label to the USA map above to show this movement.

3. REFLECT & DISCUSS How do hot spots help us understand plate tectonic processes and rates?

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