Earth Science

Regents Questions: Plate Tectonics

Name:_______________________________________________________Date:_____________Period:___

Due Date: _____________

August 2015

16 Earth’s magnetic field has reversed itself several times during the past. This pattern of magnetic reversal is best

preserved in

(1) metamorphic bedrock in mountain ranges (3) layers of sedimentary bedrock of the Grand Canyon

(2) bedrock with fossils containing radioactive carbon-14 (4) igneous bedrock of the oceanic crust

17 Which two features are commonly found at divergent plate boundaries?

(1) mid-ocean ridges and rift valleys (3) ocean trenches and subduction zones

(2) wide valleys and deltas (4) hot spots and island arcs

Base your answers to questions 38 through 40 on the diagram below and on your knowledge of Earth science. The

diagram represents a cut-away view of Earth’s interior and the paths of some of the seismic waves produced by an

earthquake that originated below Earth’s surface. Points A, B, and C represent seismic stations on Earth’s surface.

Point D represents a location at the boundary between the core and the mantle.

38 Seismic station A is 5000 kilometers from the epicenter. What is the difference between the arrival time of the

first P-wave and the arrival time of the first S-wave recorded at this station?

(1) 2 minutes 20 seconds (3) 8 minutes 20 seconds

(2) 6 minutes 40 seconds (4) 15 minutes 00 second

39 Which process prevented P-waves from arriving at seismic station B?

(1) refraction (2) reflection (3) convection (4) conduction

40 Only P-waves were recorded at seismic station C because P-waves travel

(1) only through Earth’s interior, and S-waves travel only on Earth’s surface

(2) fast enough to penetrate the core, and S-waves travel too slowly

(3) through iron and nickel, while S-waves cannot

(4) through liquids, while S-waves cannot

Base your answers to questions 59 through 61 on the map of Haiti’s location and portion of the Modified

Mercalli Intensity Scale below, on the Haiti Earthquake Intensity Map in your answer booklet, and on your

knowledge of Earth science. The map shows the location of Haiti in the Atlantic Ocean. The Modified Mercalli

Intensity Scale describes the amount and type of damage caused by an earthquake on a scale from I to XII.

A portion of this scale is shown below. Modified Mercalli intensity values for the January 12, 2010, earthquake

in Haiti are represented on the Haiti Earthquake Intensity Map in your answer booklet.

59 On the earthquake intensity map below, boundary lines have been drawn between the

Modified Mercalli intensity values of IV and V. On the map below, draw boundary lines

between the Modified Mercalli intensity values of V and VI. [1]

60 State the latitude and longitude of Savane Baptiste. Include the units and compass directions in your

answer. [1]

61 Haiti is located at a transform boundary between which two tectonic plates? [1]

Iceland Volcano Eruption Spreads Ash Cloud over Europe

On April 14, 2010, Eyjafjallajökull volcano, located in southern Iceland, explosively erupted, sending large volumes of

volcanic ash high into the atmosphere. Much of the ash fell quickly to Earth, as seen in the map, but large quantities

remained airborne and spread over Europe. Most of the ash was transported within the atmosphere below 10 kilometers.

Air traffic across the Atlantic and throughout Europe was severely

disrupted, as airlines were forced to keep jet aircraft on the ground.

85 Explain why the lithosphere in the vicinity of Eyjafjallajökull is more volcanically active than most other

regions of Earth’s surface. [1]

June 2015

11 What is the approximate P-wave travel time from an earthquake if the P-wave arrives at the seismic station 8

minutes before the S-wave?

(1) 4 minutes 20 seconds (3) 10 minutes 0 seconds

(2) 6 minutes 30 seconds (4) 11 minutes 20 seconds

Base your answers to questions 43 through 45 on the passage and cross section below and on your knowledge of

Earth science. The cross section represents one theory of the movement of rock materials in Earth’s dynamic

interior. Some mantle plumes that are slowly rising from the boundary between Earth’s outer core and stiffer

mantle are indicated.

Hot Spots and Mantle Plumes

Research of mantle hot spots indicates that mantle plumes form in a variety of sizes and shapes. These

mantle plumes range in diameter from several hundred kilometers to 1000 kilometers. Some plumes rise as blobs

rather than in a continuous streak; however, most plumes are long, slender columns of hot rock slowly rising in

Earth’s stiffer mantle. One theory is that most plumes form at the boundary between the outer core and the stiffer

mantle. They may reach Earth’s surface in the center of plates or at plate boundaries, producing volcanoes or large

domes.

43 Compared to the surrounding material, mantle plumes rise toward Earth’s surface from the core-mantle

boundary because they are

(1) cooler and less dense (3) hotter and less dense

(2) cooler and more dense (4) hotter and more dense

44 At which depth below Earth’s surface is the boundary between Earth’s outer core and stiffer mantle located?

(1) 700 km (2) 2000 km (3) 2900 km (4) 5100 km

45 The basaltic rock that forms volcanic mountains where mantle plumes reach Earth’s surface is usually

composed of

(1) fine-grained, dark-colored felsic minerals (3) coarse-grained, light-colored felsic minerals

(2) fine-grained, dark-colored mafic minerals (4) coarse-grained, light-colored mafic minerals

Base your answers to questions 72 through 76 on the modified Mercalli scale of earthquake intensity below,

on the map of Japan in your answer booklet, and on your knowledge of Earth science. The modified Mercalli

scale classifies earthquake intensity based on observations made during an earthquake. The map indicates the

modified Mercalli scale intensity values recorded at several locations in Japan during the March 11, 2011

earthquake, which triggered destructive tsunamis in the Pacific Ocean.

72 On the map in your answer booklet, a line has been drawn to separate regions with Mercalli values of V

from regions with Mercalli values of VI. Draw another line to separate regions with Mercalli values of VI

from regions with Mercalli values of VII. [1]

73 Your answer booklet lists some observations that might be made during an earthquake according to the

modified Mercalli scale. In your answer booklet, place a check mark (�) in the box if that observation most

likely was recorded at Yamagata during the March 11, 2011 earthquake. More than one box may be

checked. [1]

74 The epicenter of this earthquake was located at 38° N 142° E. Identify the type of tectonic plate boundary

that is located nearest to the epicenter of this earthquake. [1]

75 Describe one way the P-waves and S-waves recorded on seismograms at Ishinomaki and Nagano were used

to indicate that Ishinomaki was closer to the earthquake epicenter than was Nagano. [1]

76 A 25-foot high tsunami hit the Japanese city of Ishinomaki. Describe a precaution the city could take now

to protect citizens from tsunamis in future years. [1]

January 2015

15 Which tectonic feature is associated with a complex or uncertain plate boundary?

(1) Southwest Indian Ridge (2) East African Rift (3) Mariana Trench (4) Galapagos Hot Spot

Base your answers to questions 45 through 47 on the cross section of Earth below and on your knowledge

of Earth science. The cross section represents the pattern of seismic wave movement away from an earthquake.

Point W represents a location at the boundary between two layers of Earth’s interior. Points X, Y, and Z

represent seismic stations on Earth’s surface.

45 Which data best describe the depth below Earth’s surface and the density of Earth’s interior at location W?

(1) Depth: 600 km Density: changes from 3.4 g/cm3 to 5.6 g/cm3

(2) Depth: 1000 km Density: averages 4.5 g/cm3

(3) Depth: 2900 km Density: changes from 5.6 g/cm3 to 9.9 g/cm3

(4) Depth: 5100 km Density: averages 11.1 g/cm3

46 Which statement best explains why no S-waves were received directly from this earthquake at some

seismic stations?

(1) An interior Earth layer absorbs S-waves. (3) S-waves travel slower than P-waves.

(2) Earth’s mantle reflects S-waves. (4) S-waves travel only on Earth’s surface.

47 The diagram below represents the seismograms of this earthquake recorded at seismic stations X, Y, and Z.

Which table best matches each seismic station with its likely seismogram?

Base your answers to questions 62 through 65 on the map below and on your knowledge of

Earth science. The map shows the generalized ages of surface bedrock of Iceland, an island located on the

Mid-Atlantic Ridge rift. The location of the Mid-Atlantic Ridge rift is indicated. Points A and B represent

locations on the surface bedrock, which is igneous in origin. The ages of the surface bedrock, in million years

(my), are indicated in the key.

62 On the map above, identify the two tectonic plates, one on each side of the Mid-Atlantic Ridge rift at Iceland, by

writing their names on the lines provided on the map. [1]

63 On the map, draw one arrow through point A and one arrow through point B to

indicate the relative direction that each plate is moving to produce the Mid-Atlantic Ridge rift. [1]

64 Identify one dark-colored, mafic igneous rock with a vesicular texture that is likely to be found on the

surface of Iceland. [1]

65 Identify one feature in the mantle beneath Iceland that causes larger amounts of magma formation in

Iceland than at most other locations along the rest of the Mid-Atlantic Ridge rift. [1]

August 2014

16 Rifting of tectonic plates in eastern North America during the Jurassic Period was responsible for the

(1) formation of the Catskill delta (3) Alleghenian orogeny

(2) first uplift of the Adirondack Mountains (4) opening of the Atlantic Ocean

21 Oceanic crust is sliding beneath the Aleutian Islands in the North Pacific Ocean, forming the Aleutian Trench

at a

(1) convergent plate boundary between the Pacific Plate and the North American Plate

(2) convergent plate boundary between the Pacific Plate and the Juan de Fuca Plate

(3) divergent plate boundary between the Pacific Plate and the North American Plate

(4) divergent plate boundary between the Pacific Plate and the Juan de Fuca Plate

35 On the map below, points A through D represent locations on Earth’s surface.

Which location is positioned over a mantle hot spot?

(1) A (2) B (3) C (4) D

Base your answers to questions 83 through 85 on the maps and table below and on your knowledge of

Earth science. The maps show earthquake intensities (IV to IX), according to the table of the Modified Mercalli

Intensity Scale, for the 1906 and 1989 earthquakes at several locations in California.

The asterisk( * ) on each map is the location of each epicenter. The dashed line represents the location of a major

fault.

85 Explain why Santa Rosa experienced a lower Modified Mercalli intensity shaking than Salinas experienced

during the 1989 earthquake. [1]

83 Name the major fault along which both of these earthquakes occurred and identify the type of plate tectonic

boundary that is located along this fault. [1]

84 Based on the Modified Mercalli Intensity Scale, identify the perceived shaking and the observed damage

that occurred in the San Francisco area during the 1906 earthquake. [1]

85 Explain why Santa Rosa experienced a lower Modified Mercalli intensity shaking than Salinas experienced

during the 1989 earthquake. [1]

June 2014 18 The map below shows California and a section of the San Andreas Fault.

19 Compared to the oceanic crust, the continental crust is usually

(1) thicker, with a less dense granitic composition

(2) thicker, with a more dense basaltic composition

(3) thinner, with a less dense granitic composition

(4) thinner, with a more dense basaltic composition

20 Which mantle hot spot is located directly below a mid-ocean ridge plate boundary?

(1) Yellowstone (2) Iceland (3) Canary Islands (4) Hawaii

Base your answers to questions 32 and 33 on the cross section below and on your knowledge of Earth

science. The cross section represents the distance and age of ocean-floor bedrock found on both sides of the

Mid-Atlantic Ridge.

What is the primary geologic process occurring

along the San Andreas Fault?

(1) transform movement (3) subduction

(2) spreading movement (4) convergence

32 According to the cross section, every 1 million years, the ocean floor bedrock moves approximately

(1) 20 km toward the Mid-Atlantic Ridge (3) 40 km toward the Mid-Atlantic Ridge

(2) 20 km away from the Mid-Atlantic Ridge (4) 40 km away from the Mid-Atlantic Ridge

33 Which map best represents the pattern of magnetic polarity in the minerals of ocean-floor bedrock on each side

of the Mid-Atlantic Ridge?

Base your answers to questions 81 through 83 on the data table below, on the graph in your answer booklet, and on

your knowledge of Earth science. The data table shows the velocity of seismic S-waves at various depths below

Earth’s surface. The graph shows the velocity of seismic P-waves at various depths below Earth’s surface. Letter A

is a point on the graph.

81 On the graph below, plot the S-wave velocity at each depth given on the data table. Connect the plots with a

line. [1]

82 What property of Earth’s interior causes the S-waves to stop at 2900 km, but allows the P-waves to

continue? [1]

83 State the pressure and temperature of Earth’s interior at the depth indicated by point A on the graph. [1]

January2014 19 A P-wave takes 5 minutes to travel from the epicenter of an earthquake to a seismic station.

Approximately how many minutes will it take an S-wave to travel that same distance?

(1) 15 min (2) 12 min (3) 9 min (4) 4 min

20 Which two Earth layers are separated by the Moho boundary?

(1) rigid mantle and plastic mantle (3) stiffer mantle and asthenosphere

(2) outer core and stiffer mantle (4) crust and rigid mantle

31 The map below shows changes in the position of the tsunami wave front produced by the 1964 Alaskan

earthquake. The numbers indicate the time, in hours, for the wave front to reach the positions indicated by

the isolines.

If the wave front reached the Hawaiian Islands at 10:30 p.m., at approximately what time did the

earthquake occur?

(1) 1:30 p.m. (2) 5:30 p.m. (3) 3:30 a.m (4) 4:30 a.m.

32 The diagram below represents the analysis of a seismogram used to calculate an earthquake’s magnitude on

the Richter Scale. This seismogram shows the difference in arrival times, in seconds, of the first P-wave and

S-wave and the amplitude of the S-wave in millimeters.

The diagram below represents how the earthquake’s magnitude is determined by drawing a line connecting

the difference in arrival times of the P-wave and the S-wave, and the S-wave amplitude.

What is the magnitude of a recorded earthquake if the difference in arrival times of the first P-wave and

S-wave is 2 seconds and the S-wave amplitude is 20 millimeters?

(1) 3.8 (2) 2.0 (3) 3.0 (4) 4.8

Base your answers to questions 36 through 38 on the passage and map below and on your knowledge of

Earth science. The map shows the locations of the Mt. Redoubt volcano and Anchorage, Alaska.

Mt. Redoubt Volcano

In Anchorage, Alaska, scientists are monitoring sensors located on nearby Mt.

Redoubt. The sensors measure seismic activity at the top of the volcano. No one lives

near the volcano itself, so there is no danger to humans from lava flows, but ash can be

dangerous when breathed in, and can damage airplanes and automobiles if the ash is

drawn into their engines. When Mt. Redoubt erupted in 1989, a huge ash cloud

reached an approximate height of 7.6 miles above sea level, and spread ash across

Alaska for five months. The ash was composed largely of silica, which cooled rapidly as

the ash rose into the atmosphere. In March 2009, Mt. Redoubt erupted again.

36 Mt. Redoubt’s seismic activity is due to the interaction of which two tectonic plates?

(1) Pacific Plate and Eurasian Plate (3) North American Plate and Pacific Plate

(2) Eurasian Plate and North American Plate (4) Philippine Plate and Eurasian Plate