Astronomy and earth science chapter 6

In areas where unconsolidated materials are saturated with water, earthquakes can turn stable soil into a fluid during a phenomenon called _____.

liquefaction

Long-range earthquake forecasts are based on the premise that earthquakes are _____.

repetitive

The study of earthquakes is called _____.

seismology

The belt from about 105 to 140 degrees away from an earthquake where no P waves are recorded is known as the _____.

shadow zone

The two most common types of folds are anticlines and _____

synclines

. The epicenter of an earthquake is located using the distances from a minimum of _____ seismic stations.

three

The difference in _____ of P and S waves provides a method for determining the epicenter of an earthquake

velocities

T/F- Most major episodes of mountain building have occurred along DICERGENT plate boundaries.

Convergent

T/F- Earthquakes with a Richter magnitude less that EIGHT are usually not felt by humans.

False- 2

T/F- The lithosphere is situated BELOW the asthenosphere

False- above

T/F- The adjustments that follow a major earthquake often generate smaller earthquakes called FORESHOCKS

False- aftershocks

T/F- P waves arrive at a recording station AFTER S waves.

False- before

T/F- Fluids (gases and liquids) CANNOT transmit P waves.

False- can

T/F- Earthquakes in the central and eastern United States occur MORE frequently than along plate-boundary areas.

False- less

T/F- The boundary that separates the crust from the underlying mantle is known as the SHADOW discontinuity.

False- mohorovicic

T/F- The study of earthquakes is called SEIMOGRAPHY

False- seismology

T/F- Most tsunamis result from HORIZONTAL displacement of the ocean floor during an earthquake

False- vertical

Which of the earthquake body waves cannot be transmitted through fluids?

S waves

T/F- A refined Richter scale is used to describe earthquake MAGNITUDE

True

T/F- Earth's INNER core is a solid metallic sphere

True

T/F- Earthquake BODY waves are divided into two types called primary (P) waves and secondary (S) waves.

True

T/F- Earthquake waves that travel through Earth's interior are called BODY waves.

True

T/F- Most earthquakes occur along faults associated with PLATE boundaries.

True

T/F- Most folds result from COMPRESSIONAL stresses in the crust.

True

T/F- Most of our knowledge of Earth's interior comes from the study of EARTHQUAKES

True

T/F- No reliable method of SHORT-RANGE earthquake prediction has yet been devised.

True

T/F- Strike-slip faults that are associated with plate boundaries are called TRANSFORM faults.

True

T/F- The EPICENTER of an earthquake is the location on the surface directly above the focus.

True

T/F- The continental crust is mostly made of GRANITIC rocks.

True

T/F- The farther a station is from an earthquake, the GREATER the difference in arrival times of the P and S waves.

True

T/F- The mantle is SOLID because both P and S waves travel through it.

True

T/F- To locate an epicenter, the distance from THREE or more different seismic stations must be known

True

T/F- Vibrations known as earthquakes occur as rock slips and ELASTICALLY returns to its original shape.

True

An earthquake with a magnitude of 6.5 releases _____ times more energy than one with a magnitude of 5.5

30

It is estimated that over _____ earthquakes that are strong enough to be felt occur worldwide annually.

30000

Where two oceanic plates converge, _____ subduction zones often occur.

Aleutian-type

Where oceanic crust is being thrust beneath a continental mass, _____ subduction zones often occur

Andean-type

The rock immediately above a fault surface is commonly called the _____.

Hanging-wall

Which one of the following mountain ranges has formed where continental crusts have converged?

Himalaya Mountains

The cool, rigid layer of Earth that includes the entire crust as well as the uppermost mantle is called the_____.

Lithosphere

Which earthquake body wave has the greatest velocity?

P waves

It is assumed that many of the terrains found in the North American Cordillera were once crustal fragments scattered throughout the eastern _____ ocean basin.

Pacific

The San Andreas fault zone separates two great sections of Earth's crust, the North American plate and the _____ plate

Pacific

Dense rocks like _____ are thought to make up the mantle and provide the lava for oceanic eruptions.

Peridotite

Earthquake epicenters are most closely correlated with _____.`

Plate boundaries

Dip-slip faults are classified as _____ faults when the hanging wall moves up relative to the footwall

Reverse

The adjustments of materials that follow a major earthquake often generate smaller earthquakes called _____.

aftershocks

Faults where the movement is primarily vertical are called _____ faults.

dip-slip

The location on the surface directly above the earthquake focus is called the _____.

epicenter

The source of an earthquake is called the _____.

focus