Earth's Dynamic Crust

The point of the earths surface directly above the point where an earthquake occurs is called the:

• Focus

• Epicenter

• Fracture

• Fault

Tags

NGSS.MS-ESS3-2

When two tectonics plates collide, oceanic crust usually subducts beneath continental crust because oceanic crust is composed of igneous rocks that has

• low density and is mafic

• low density and is felsic

• high density and is mafic

• high density and is felsic

Alternating parallel bands of normal and reversed magnetic polarity are found in the basaltic bedrock on either side of the

• Mid-Atlantic Ridge

• Yellowstone Hot Spot

• San Andreas Fault

• Peru-Chile Trench

Tags

NGSS.MS-ESS2-3

In which cross section below do the arrows best show the convection occurring within the asthenosphere beneath line XY?

• 1

• 2

• 3

• 4

Tags

NGSS.MS-ESS2-1

Samples of ocean floor bedrock were collected at points A, B, C and D. Which sequence shows the correct order of the age of the bedrock from oldest to youngest?

• D>C>B>A

• A>D>B>C

• C>B>D>A

• A>B>D>C

Tags

NGSS.MS-ESS2-2

NGSS.MS-ESS1-4

The boundary between which two tectonic plates is most similar geologically to the plate boundary at the Mid-Atlantic Ridge?

• Eurasian and Indian-Australian

• Nazca and South American

• Pacific and Nazca

• Cocos and Caribbean

Tags

NGSS.MS-ESS2-3

Active volcanoes are most abundant along the

• edges of tectonic plates

• equatorial ocean floor

• 23.5^oN and 23.5^oS parallels of latitude

• eastern coastlines of continents

Tags

NGSS.MS-ESS2-3

NGSS.MS-ESS3-2

Both P-waves and S-waves were received at seismic stations A and B, but only P-waves were received at seismic stations C and D. Which statement best explains why this occurred?

• S-waves are much weaker than P-waves.

• S-waves travel faster than P-waves.

• The liquid outer core prevents S-waves fromtraveling to seismic stations C and D.

• The solid outer core prevents S-waves fromtraveling to seismic stations C and D

If a seismic station is 3200 km from an earthquake epicenter, which is the time needed for an S-wave to travel from the epicenter to the seismic station?

• 4 min 40 sec

• 6 min 0 sec

• 10 min 40 sec

• 11 min 10 sec

The first P-wave of an earthquake travels 5600 kilometers from the epicenter and arrives at a seismic station at 10:05 a.m. At what time did this earthquake occur?

• 9:49 a.m.

• 10:02 a.m.

• 9:56 a.m

• 10:14 a.m.