Exam 8: Earthquakes and Earths Interior

An earthquake of magnitude 7.0 has an amplitude ____________________ times as large and releases ____________________ times as much energy, respectively, as a magnitude 6.0 earthquake.

The structural layer of Earth that is liquid is the ____________________ ____________________.

What evidence do scientists use to estimate the density and composition of the core?

The average geothermal gradient near Earth's surface is:

What is Earth's average density, what are the average surface rock densities, and what does this tell us about the interior of Earth?

The opening of large fissures that swallow people is a significant source of danger generated by earthquakes.

Why do we know that the geothermal gradient near the surface cannot continue very deeply into Earth?

On the Richter Scale, an earthquake of 6.0 releases ten times as much energy as an earthquake of 5.0.

The separation of the continental crust and its submergence beneath the oceanic crust are significant sources of danger created by earthquakes.

The most damage from the 1906 San Francisco earthquake was caused by:

The increase of temperature with depth is known as the ____________________.

The composition of the core is:

Why has it been suggested that large earthquakes might be prevented by injecting water along isolated portions of fault zones that have been inactive for an unusually long time? When was this technique discovered?

Why do structures located on thick, soft sediment, especially water-saturated or artificial fill, suffer much greater damage than structures built on bedrock?

Within which belt or zone do the majority of earthquakes occur?

The estimated average geothermal gradient in the mantle is:

What does the Richter Magnitude Scale measure, and why are scales of this type used more frequently than intensity scales?

Seismology has produced a great amount of information about:

The type of building construction and population density in the area of an earthquake are factors that can affect the intensity on the Modified Mercalli Intensity Scale.

The percentage of all earthquakes that occur along a plate boundary is nearly: