Download Plate Tectonics, Earthquakes, and Volcanoes Study Guide

Plate Tectonics, Earthquakes, and Volcanoes Study Guide
Name __________________________________ period____
1.Seafloor spreading occurs because ____.
2.In order to complete a convection current, the rising material must eventually ____ Earth.
3.Active volcanoes are most likely to form at ____.
4.According to the diagram, what type of plate boundary occurs between the North American Plate and the Eurasian
Plate?
5.According to the diagram, what type of plate boundary occurs between the Nazca Plate and the South American Plate?
6.Why are there earthquakes, but few volcanoes in the Himalayas?
7.Glacial deposits often form at high latitude near the poles. Explain why glacial deposits have been found in Africa.
8.Which statement is true of P-waves?
9.In the process of sea-floor spreading, where does molten material rise from the mantle and erupt?
10.The difference between the arrival times of ______ waves and ______ waves at a recording station helps scientists
determine the distance from the epicenter of an earthquake.
11.Hollister, California, lies directly over the San Andreas Fault. Every five or six years the streets and sidewalks crack
and have to be repaired. Explain.
12.Describe the Pacific Ring of Fire.
13.Describe the convection currents of Earth’s mantle.
14.Explain why volcanoes do not form along the San Andreas Fault
15.Describe a divergent boundary?
16.Describe the lithosphere and the asthenosphere?
17.Suppose the arrows in the diagram represent patterns of convection in Earth’s mantle. Which type of plate boundary is
most likely to form along the region labeled “A”
18.What is happening at the region marked “B” on the diagram?
19.Describe the outcome of the collision between oceanic and continental crust
20.When Alfred Wegener first proposed his theory of continental drift, most geologists did not immediately accept it.
Many expressed skepticism because the theory did not explain what force was strong enough to move
continents. Later, scientists investigating the ocean floor found evidence that explained how continents were
able to move. Plate tectonics, which grew from the theory of continental drift, now explains how continents
move over time.
How was the initial skepticism of geologists useful to the scientific process?
21.The islands of Hawaii have been produced when hot magma from inside Earth comes to the surface and cools. Many
years after it erupts, the hardened magma becomes home to plants, animals and other living things.
What is the most logical prediction about the newly erupted magma?
Use this diagram to answer the questions below
22.The feature labeled D is part of the continuous underwater mountain range that circles Earth. It is called ___
23.The feature labeled C represents some of the deepest spots on the ocean floor. These areas are called ____
24.If one of Earth’s plates moves 5 centimeters per year, how far will it move in 500 years?
Use this diagram to answer the questions below
25.Which type of boundary is shown at B?
26.Earthquakes would most likely occur ___
27.Volcanic Ash clouds often change climate temporarily, making it colder. Why does this change occur?
28.In October of 2004, Mount St. Helens volcano began to release steam and ash, warning signs of an eruption. An
unmanned vehicle containing cameras was flown over the volcano to photograph and monitor its activity.
Why was unmanned, remote -controlled technology used for this investigation?
29.A news report states that an earthquake occurred in your area yesterday afternoon. Some people commented that the
vibrations felt like those of a passing truck, but no damage occurred. How would you rate this earthquake on
the Mercalli scale?
30.In which location would you most likely find volcanoes?
31.Hot columns of mantle material slowly heat, rise, cool and sink through Earth’s asthenosphere. This type of heat
transfer is called__
32.Most geologists rejected Alfred Wegener’s idea of Continental Drift because___
33.A community has just built a street across a strike-slip (transverse) fault that has frequent earthquakes. How will
movement along the fault affect the street? Movements along the fault affect the street?
34.Geologists know that wherever plate movement stores energy in the rock along faults___
Use the graph to answer the following questions.
35.In what order did the seismic waves arrive at the seismograph station?
36.Which type of seismic wave produced the largest ground movement?
37.What was the difference in arrival times for the P and S waves?
38. What would the seismograph look like several hours after this earthquake? How would it change if an after shock
occurred?
New Madrid Earthquakes
From December 1811 to February 1812, three large earthquakes struck near New Madrid, Missouri.
The earthquakes were felt over an area of at least 2 million square miles, from Canada to New Orleans. The
earthquakes toppled chimneys as far away as Richmond, Virginia, and Cincinnati Ohio. The shaking rang
church bells in Washington D.C. and in Boston 1,100 miles away.
The land surface underwent significant changes over an area of 30,000 to 50,000 square miles. The
ground was observed to move in long, low waves. As these waves rolled across the surface, large parallel
fissures opened in the ground. Some of these were 60 to 700 feet long, with one reported to have a length of
5 miles. The land surface was raised several feet in some areas and lowered in others. Some of the lowered
areas flooded to form lakes. Reel foot Lake in Tennessee is one of these lakes. It is 8-10 miles long and 2-3
miles wide.
Since only about 3,000 people lived in the region, the damage was less that would be expected from
such large quakes. No seismographs recorded the earthquakes, but scientists have estimated the strength from
eyewitness damage reports as measuring 7.2, 7.1 and 7.45 on the moment magnitude scale.
39.Explain how earthquakes that were so high on the moment magnitude scale didn’t cause much property damage
40.What is the best explanation as to why no seismographs recorded the New Madrid Earthquakes?