stress the amount of force per unit area that acts on a rock strain any change in a rock's shape or volume caused by stress Faults

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1 Section 1 Review! deformation the bending, tilting, and breaking of Earth's crust; the change in the shape of rock in response to stress: fault a break in a body of rock along which one block slides relative to another; a form of brittle strain fold a form of ductile strain in which rock layers bend, usually as a result of compression isostasy a condition of gravitational and buoyant equilibrium between Earth's lithosphere and asthenosphere stress the amount of force per unit area that acts on a rock strain any change in a rock's shape or volume caused by stress 1. Compare Complete the Venn diagram below to compare folds and faults. Faults 2. Apply Concepts What would you expect a rock that has expelienced tension to look like? 3. Infer About 20,000 years ago, many areas in northern North Amelica were covered with glaciers. Since then, the glaciers have melted. The lithosphere in many of these areas is now expeliencing uplift. Why is this? 4. Describe How can a geologist tell if a fold is a syncline or an anticline? Copyright Holt McDougal. All rights reselved. Holt McDougal Earth Science 168 Deformation of the Crust -.. _

2 Name Class Date Section 2 Review dome mountain a circular or elf,jptical, almost symmetrical elevation or structure In which the stratified rock slopes downward gently from the central point of folding faull-block mountain a mountain that forms where faulting breaks Earth's crust into large blocks, which causes some blocks to drop down relative to other blocks folded mountain a mountain that forms when rock layers are squeezed together and uplifted mountain range a series of mountains that are closely related in orientation, age, and mode of formation 1. Describe What characteristics do the mountains in a mountain range have in common? 2. Identify What are three types of plate collisions that can form mountains? 3. Compare What are the main differences between mountains that form where two continents collide and mountains that form where an oceanic plate collides with a continental plate? 4. Describe What is one difference between the way that folded mountains and fault-block mountains form? 5. Apply Concepts A geologist is studying a mountain. The mountain is small and round. Its sides are not very steep. How did the mountain most likely form? Explain your answer. Holt McDougal Earth Science 174 Deformation of the Crust

3 Section 1 Review 0 t-\ PT,~\ body wave a seismic wave that travels through the body of a medium earthquake a movement or trembling of the ground that is caused by a sudden release of energy when rocks along a fault move elastic rebound the sudden return of elastically deformed rock to its undeformed shape epicenter the point on Earth's surface directly above an earthquake's starting point, or focus fault zone a region of numerous, closely spaced faults focus thelocation within Earth along a fault at which the first motion of an earthquake occurs P wave a primary wave, or compression wave; a seismic wave that causes particles of rock to move in a back-and-forth direction parallel to the direction in which the wave is traveling shadow zone an area on Earth's surface where no direct seismic waves from a particular earthquake can be detected surface wave a seismic wave that travels along the surface of a medium and that has a stronger effect near the surface of the medium than it has in the interior S wave a secondary wave, or shear wave; a seismic wave that causes particles of rock to move in a side-to-side direction perpendicular to the direction in which the wave is traveling 1. Describe Relationships How is elastic rebound related to eruihquakes? 2. Explain Why do most earthquakes happen at plate boundaries? 3. Compare Describe three differences between P waves and S waves. 4. Describe What are shadow zones, and why do they exist? Holt McDougal Earth Science 180 Earthquakes

4 , Section 2 Review intensity inearth science, the amount of damage caused by an earthquake magnitude a measure of the strength of an earthquake seismogram a tracing of earthquake motion that is recorded by a seismograph seismograph an instrument that records vibrations in the ground 1. Describe Relationships How are a seismograph and a seismogram related? 2. Explain Two different cities experienced the same earthquake. In one city, scientists said that the earthquake had a level V intensity. In the other city, scientists said that the earthquake had a level VII intensity. Explain how this could be true. 3. Describe How do scientists find the location of an earthquake's epicenter? 4. Apply Concepts An earthquake affected the towns of Quakeville and Shaketown. Quakeville was closer to the epicenter than Shaketown was. The seismogram on the left is from Quakeville. The picture on the right shows part of the seismogram from Shaketown. Complete the seismogram from Shaketown. P waves arrive~ Seismogram from Quakeville Seismogram from Shaketown waves arrive /Surface. waves arnve ri ~~~ I I I I I I I I I I I I I I I I I o Time in minutes after earthquake Time in minutes after earthquake Holt McDougal Earth Science 184 Earthquakes

5 Section 3 Review ~ ~PT \ ~ seismic gap an area along a fault where relatively few earthquakes have occurred recently but where strong earthquakes are known to have occurred in the past tsunami a giant ocean wave that forms after a volcanic eruption, submarine earthquake, or landslide 1. Explain What causes a tsunami? 2. Describe What are seismic gaps, and why are they important? 3. Identify What are two ways an earthquake can damage a building? 4. Infer Scientists examined the rocks at a fault zone, and they predicted that an earthquake might happen there. What do you think they found? 5. Identify In the table below, list steps that people who live in areas that have high earthquake-hazard levels should take. List at least two steps in each box. Before an Earthquake During an Earthquake After an Earthquake Holt McDougal Earth Science 188 Earthquakes

6 , Section 1 Review hot spot a volcanically active area of Earth's surface, commonly far from a tectonic plate boundary lava magma that flows onto Earth's surface; the rock that forms when lava cools and solidifies magma liquid rock produced under Earth's surface volcanism any activity that includes the movement of magma toward or onto Earth's surface volcano a vent or fissure in Earth's surface through which magma and gases are expe'lled 1. Define In your own words, define volcanism. 2. Describe Complete the table below to describe how volcanoes form in different areas. Place Where Volcanoes Form Subduction zones Description Why Magma Forms There A mantle plume rises to the surface. Two plates move apart. As the plates move apart, the pressure on the rock below decreases. The decreased pressure causes the rock to melt. 3. Compare What is the main difference between how a pluton forms and how a volcano forms? 4. Apply Concepts The map below shows the locations of many volcanoes. On the map, circle three volcanoes that are probably found at hot spots. ~~"-/ _,_,/", /., -- Plate boundary Holt McDougal Earth Science 194 Volcanoes

7 Name Class Date Section 2 Review ~\40T 13 caldera a large, circular depression that forms when the magma chamber below a volcano partially empties and causes the ground above to sink felsic describes magma or igneous rock that is rich in feldspars and silica and that is generally light in color mafic describes magma or igneous rock that is rich in magnesium and iron and that is generally dark in color pyroclastic material fragments of rock that form during a volcanic eruption 1. Explain Why does felsic lava produce explosive eruptions more often than mafic lava does? 2. Compare Give one similarity and one difference between lapilli and volcanic blocks. 3. Describe How do calderas form? 4. Infer Which would be more likely to increase the steepness of a volcanic cone--a quiet eruption or an explosive eruption? Explain your answer. 5. Explain Scientists today are studying many active volcanoes around the world. They are even studying volcanoes that have not erupted for hundreds or thousands of years. What is the most likely reason they are studying these volcanoes? Holt McDougal Earth Science 200 Volcanoes