CH 5 Geoscience

The elastic rebound theory for the origin of earthquakes was first proposed by ____________ following the ____________ earthquake.

When an earthquake occurs, energy radiates in all directions from its source. The source is also referred to as the __________.

Which one of the following statements is correct?

____________ have the *highest* velocities.

Which one of the following is true regarding tsunamis?

The amount of destruction caused by earthquake vibrations is affected by __________.

On a typical seismogram, ____________ will show the highest *amplitudes*.

Major earthquakes are often followed by somewhat smaller events known as __________.

The ____________ magnitude scale is a measure of the energy released. It does not directly measure the extent of building damage.

The instrument which records earthquake events is termed a __________.

____________ is the maximum possible damage designation on the Mercalli scale.

The position on Earth's surface *directly above* the earthquake source is called the __________.

The mechanism by which rocks store and eventually *release energy* in the form of an earthquake is termed __________.

Overall, this type of seismic wave is the most destructive.

Approximately how much more energy is released in a 6.5 Richter magnitude earthquake than in one with magnitude 5.5?

P waves ____________.

The Mercalli Scale is a scale from ____________.

The distance between a seismological recording station and the earthquake source is determined from the __________.

The Richter magnitude of an earthquake is determined from the __________.

Which one of the following best characterizes tsunamis?

The ____________ earthquake was accompanied by extensive fire damage.

A ____________ refers to the tendency for a foundation material to lose its *internal cohesion* and fail mechanically during earthquake shaking.

The record of an earthquake obtained from a *seismic instrument* is a(n) __________.

Most of our knowledge about Earth's interior comes from __________.

Which one of the following statements about the *crust* is NOT true?

The dense core of Earth is thought to consist predominantly of __________.

The lithosphere is defined as __________.

The average composition of the *oceanic* crust is thought to approximate that of __________.

The average composition of the *continental* crust most closely approximates that of __________.

The Earth's magnetic field originates by ____________.

The asthenosphere is located __________.

A ____________ fault has little or no vertical movements of the two blocks.

In a ____________ fault, the hanging wall block move up with respect to the *footwall* block.

In thrust faulting, ____________.

A graben is characterized by ____________.

The mountains and valleys of the Basin and Range Province of western United States formed in response to ____________.

In a normal fault ____________.

A transform fault is ____________.

Brittle deformation would be favored over plastic deformation in which of the following conditions?

A thrust fault is best described as ____________.

A horst is ____________.

A syncline is ____________.

The Black Hills of South Dakota are a good example of a(n) __________.

Large circular downwarped structures are called __________.

Which of the following combinations should favor folding rather than faulting?

*Tensional forces* normally cause which one of the following?

The ____________ in California is the boundary between the North American and Pacific plates.

A(n) ____________ is a thick accumulation of sediments and small, tectonic blocks formed of material scraped off a descending, lithospheric plate.

The Sierra Nevada, CA, and Teton, WY ranges are examples of ____________.

A good example of a present-day, passive, continental margin is the ____________.

The ____________ are a geologically old mountain range folded and deformed during the Paleozoic.

The term ____________ refers specifically to geologic mountain building.

The ____________ is (are) characterized by terrane accretion that has been active throughout most of Mesozoic and Cenozoic time.

Folded limestones that occur high in the Himalayas were originally deposited as sediments in a ____________.

An earthquake occurred on the Erie fault 5 kilometers beneath *San Gabriel*. Damage from the earthquake was greatest in nearby Fremont. The farthest report of shaking was recorded in Stockton. Where was the earthquake's epicenter?

What type of fault generated the Hebgen Lake earthquake, Montana?

Which figure best illustrates a convergent plate boundary between oceanic and continental plates?

Which point on the graph shown below is most likely a mega-earthquake?

How much would ground motion increase between a magnitude 4.5 and 5.5 earthquakes?

Three sites (L1, L2, L3) record earthquake magnitude and earthquake intensity for the same earthquake. L1 is located closest to the focus and L3 is farthest away. Where is the intensity greatest, and what happens to the earthquake magnitude calculated at the different sites?

A transform fault is___.

Suppose you were near the epicenter and felt the Earth move as if you were in the ocean. What type of seismic wave would you have experienced?

How much more grounds motion does a Richter scale magnitude 5 earthquake generate compared to a richter magnitude 3 earthquake

This earth generated hazard can occur when seismic waves shake saturated soils.

What is the Mercalli Intensity scale based upon?

The ___ in California is the boundary between the North American and Pacific plates.

On a typical seismogram,____ will show the highest amplitudes.

When an earthquake occurs, energy radiates in all directions from its source. the source is also refered to as the___.

P waves____.

Suppose two earthquakes with the same magnitude, depth, and relative motion occur in two cities, A and B. City A is near a plate boundary, city B is far from a plate boundary. Which earthquake would cause the most shaking farthest from the epicenter?