exam 3 ch8 quiz&activity

Arrange the following images from earliest to latest to model the formation of a new fault.

1,2,3

order events chronologically that can lead to a subduction-related tsunami. slip occurs and the overriding plate moves back into position, displacing a large amount of the seafloor the overriding plate deforms, and strain builds a bulge of water is created at the sea surface and spreads out as a series of waves the overriding plate "sticks" to the subducting slab

1. the overriding plate "sticks" to the subducting slab 2. the overriding plate deforms, and strain builds 3. slip occurs and the overriding plate moves back into position, displacing a large amount of the seafloor 4. a bulge of water is created at the sea surface and spreads out as a series of waves

Even though earthquake prediction is not highly reliable, what do geologist know about them?

1. we cannot predict when an earthquake will occur; we can only estimate the probability that an earthquake will occur over a set period of time 2. recurrence intervals can provide a measure of annual earthquake probability 3. earthquakes are more frequent along plate boundaries than at intraplate locations

interpret the travel-time curve shown. If the P-wave arrived at Station 2 at 4:43pm, approximately when did the earthquake occur?

4:36pm

The Interactivity portion of the Earthquake Animation will guide you through the process of analyzing data from different seismic stations to determine the epicenter location and magnitude for an earthquake in the east-central region of the United States. Based on your analysis of the data in this activity, which of the following values is closest to the magnitude of this earthquake? 4.5 6.5 3.5 5.5

5.5

examining sedimentary bedding in a geologic study reveals that disrupted layers formed 260, 820, 1200, 2100, and 2300 years ago. What is the recurrence intervals of the earthquakes that caused the disruption?

510 years

interpret the travel-time curve shown. How far away is the earthquake epicenter from station 3?

6,000km

Identify the true statement. A. An earthquake of magnitude 6 has 1,000 times the amplitude of a magnitude 3 quake. B. Large earthquakes occur more frequently than small ones. C. The Mercalli scale is no longer used because it has been replaced by modern measures of earthquake magnitude. D. An earthquake of magnitude 6 has twice the amplitude of a magnitude 3 quake.

A

Identify statements true of earthquakes. A.An estimated one million earthquakes occur each year, but most of them are small. B.Most earthquakes are large and destructive. C.Most earthquakes occur along plate boundaries. D.Most earthquakes are the consequence of plate tectonics.

A, C, D

Interpret the seismogram shown. What type of features do A,B,C, and D represent?

A: P-wave arrival B: S-wave arrival C: Surface waves D: Aftershock

identify the true statement: A. S-waves are compressional body waves, while P-waves are shear body waves B. Surface waves typically have the largest amplitude C. P-waves and S-waves are seismic surface waves D. Surface waves are the first to show up on a seismogram recording of a quake

B

Watch the Introduction of the Tsunami Initiation and Arrival Animation and then click on the Examples tab under the Topics menu to get information about particular tsunamis. The largest and most destructive tsunamis in human history have been associated with which of the following? A.normal faulting on the seafloor B.subduction-zone earthquakes C.landslides D.iceberg calving E.volcanic eruptions

B, E

Label the hanging wall and footwall show in the image. What is B and what is A? in this type of fault, the hanging wall has moved __________ relative to the footwall

B: footwall A: hanging wall down

Identify the statement that is true about the 2010 Haiti earthquake. A. Faulting occurred along a divergent plate boundary between the Caribbean and North American plates. B. The earthquake generated a tsunami that was responsible for the majority of the lives lost. C. The likelihood of an earthquake was great because stress had been building on the fault for more than 200 years. D. Shaking was amplified as waves passed from weak sediments into harder bedrock.

C

Identify the statement that is true about tsunami events. A. The wavelengths of tsunami waves are often shorter than those of wind-driven waves. B. The velocity of a tsunami wave increases when the wave moves from open ocean to shallower water. C. Tsunami waves that affect the local area around an earthquake's epicenter are called far-field tsunamis. D. Tsunamis may be generated by underwater earthquakes, eruptions of island volcanoes, or submarine landslides.

D

Identify the true statement. A. Earthquake intensity is based on ground motion recorded by a seismometer; magnitude is based on the amount of damage produced. B. Contour lines representing Richter values are used to delimit zones of earthquake intensity; the greater the quake, the higher the intensity values and the wider the zones. C. Earthquakes never have hypocenters (foci) deeper than about 100 km (60 miles). D. Seismic waves become smaller in amplitude with increasing distance from the epicenter.

D

Identify the true statement. A. All of the possible answers are correct. B. Seafloor fracture zones are associated with frequent earthquakes. C. Earthquakes never happen in the interior of plates, only at their boundaries. D. Shallow-focus earthquakes are associated with divergent and transform boundaries; convergent plate boundaries also produce deep earthquakes.

D

Match the following plate boundary characteristics to the corresponding fault type. - associated with divergent plate boundaries - associated with transform boundaries - associated with convergent plate boundaries *place them under normal fault, reverse fault, or strike-slip fault*

Normal fault: associated with divergent plate boundaries Reverse fault: associated with convergent plate boundaries Strike-slip fault: associated with transform boundaries

which of the following statements is true?

R-waves cause the earth's surface to move up and down

cite natural phenomena that can cause tsunami formation

landslides earthquakes volcanic eruptions

The location of major earthquakes and volcanic eruptions

are usually along plate boundaries

Examine the three seismograms. They were recorded by three different stations during the same earthquake. They all have the same x-axis and y-axis scales. Based on what you have learned about wave amplitudes and S-P intervals, assign the seismograms relative distances to the epicenter using the labels to the right. based on graph which is B,C, and A: - intermediate distance from epicenter - closest to epicenter - farthest from epicenter

b: intermediate distance from epicenter c: farthest from epicenter a: closest to epicenter

in this illustration,

block x is the hanging wall

Use the Travel Time function of the Interactivity to find the distance between each of your cities (their respective seismometers) and the epicenter of the earthquake. Compare the S-P values with the distance (km) values. Which of the following are correct? A.The shorter the time interval is between the arrival of the S- and the P-waves, the farther the seismometer is from the epicenter. B.The smaller the S-P value is, the farther the seismometer is located from the epicenter. C.The larger the S-P value is, the farther the seismometer is located from the epicenter. D.The longer the S- and P-waves travel, the farther apart their wave fronts are in kilometers. E.The farther the epicenter is, the greater the time difference in the arrival of the P- and S-waves at a seismometer.

c,d,e

seismometers

can "feel" (or record) large earthquakes that happen on the opposite side of the world

Liquefaction

can cause wet, silty, or sandy sediment to turn into an unstable slurry

The images show the internal structure (left) and finished exterior (right) of the Pearl River Tower, a modern skyscraper recently built in Guangzhou, China. This building most clearly shows which of the following earthquake engineering elements? - crossbeams to increase shear strength - shock absorbers to reduce vibrations - support columns wrapped in cable to provide extra strength

crossbeams to increase shear strength

which term describes the current theory of earthquake formation?

elastic rebound

Which of the following earthquake phenomena is the LEAST likely to directly injure or kill humans?

ground shaking

fault creep

is movement along a fault without an accompanying earthquake

The richter scale

is today termed a local magnitude (Ml) reading

a tsunami

may be just a broad, gentle swelling out at sea but grows as it approaches shore

which tectonic processes are likely to be associated with earthquakes?

plate subduction movement along plate boundaries mountain building formation of ocean basins

This map includes three seismograph stations (1, 2, and 3) and circles showing the calculated distance between the stations and an earthquake epicenter. Which of the four locations (A, B, C, or D) represents the epicenter of the earthquake?

point d

P and S wave arrival times are indicated on seismogram records for three stations. Which of the three stations shown below is farthest from the earthquake that generated the waves?

station 3

what does this figure illustrate? two blocks moving diff ways (divergent)

strike-slip faulting

Using this earthquake hazard map for the united states, determine which area in the list below has the highest earthquake hazard: - the washington coast -minnesota - the gulf coast - the south carolina coast

the washington coast

The tsunami event of December 26,2004

was first noticed as a withdrawal of the sea along the beachfront

which of the following is a good technique for building earthquake-resistant structures?

wrapping bridge supports with steel cables