Chapter 9 Quiz

Approximately how much more energy is released in a 6.5 Moment Magnitude earthquake than in one with Mw of 5.5?

30 times

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

Oceanic crust is enriched in potassium, sodium, and silicon.

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

Reid; 1906 San Francisco

Which one of the following statements is correct?

S waves travel through solids and P waves travel through liquids

The ________ earthquake was accompanied by extensive fire damage.

San Francisco, 1906

Which one of the following best characterizes tsunamis?

They have relatively small amplitudes compared to their very long wavelengths.

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

XII

The lithosphere is defined as ________.

a rigid layer of crustal and mantle material

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

aftershocks

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

arrival time of P and S waves

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

design of structures, intensity and duration of the vibrations, and nature of the surface material

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

epicenter

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

focus

The asthenosphere is located ___________.

in the upper mantle

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

iron

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

liquefaction

The ________ Magnitude is a measure of the total energy released. It does not directly measure the extent of building damage.

moment

________ have the highest velocities.

primary waves

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

seismic waves

The instrument that records earthquake events is termed a ________.

seismograph