Geology Chapter 12 Practice Quiz

Earthquakes and Volcanoes

• Volcanic explosions generate seismic waves that can cause earthquakes.
• Volcanoes exert pressure on the crust, leading to faulting.
• Steep, unstable slopes of volcanoes can result in landslides that create ground shaking.
• Movement of magma within or beneath a volcano can trigger earthquakes.

Earthquake Localization Evidence

• Seismograms from three monitoring stations are essential for pinpointing earthquake locations.

Earthquake Causes

• The formation of an oceanic trench is a common cause of earthquakes.

P-wave Velocity Influences

• The rigidity, density, and compressibility of geological materials affect the velocity of P-waves.

Earthquake Forecasting Techniques

• Long-range forecasting relies on historical data, tectonic settings, and seismic activity patterns.
• Short-term predictions are complex and still evolving.

Importance of Prehistoric Earthquakes

• Studying prehistoric events aids in understanding recurrence intervals and potential magnitude, providing critical information for future seismic risk planning.

Tsunami Generation

• Sudden fault movements that uplift or downdrop the seafloor can lead to tsunami formation.

Christchurch vs. Canterbury Earthquakes

• The 2011 Christchurch earthquake inflicted more damage due to proximity to cities and prior structural damage from earlier quakes.

1906 San Francisco Earthquake Damage

• A tsunami was not a contributing factor in the damage from the 1906 San Francisco earthquake.

1964 Alaskan Earthquake

• One of the largest recorded earthquakes, caused by thrusting along a subduction zone.

Deaths from Earthquakes

• The majority of earthquake-related fatalities result from building collapses.

Damage Aftershocks

• Extensive post-event destruction can occur from tsunamis, fires, and flooding caused by dam failures or ground subsidence.

Building Safety in Earthquake-Prone Areas

• Constructing rigid concrete or masonry buildings is not advisable in high-risk earthquake zones.

Earthquake Location Determination

• The position of recent earthquakes is identified through seismic records from three or more monitoring stations.

Characteristics of S-waves

• S-waves cannot travel through liquids and displace rock perpendicularly to their travel direction.

Characteristics of P-waves

• P-waves compress and expand rock in the same direction as their propagation.

Earthquake Generation Mechanisms

• Earthquakes within continental plates can result from magma intrusion, rifting, normal faulting, transform faults, or stress on preexisting faults.

Earthquake Occurrence

• The majority of earthquakes are concentrated along tectonic plate boundaries.

Earthquake Depth Insights

• An area with shallow, intermediate, and deep earthquakes indicates proximity to a subduction zone, where shallow quakes are often closer to trenches.

Stress in Faults

• Maximum stress and elastic strain in rocks along a fault occur just before an earthquake strikes.

Main Cause of 2004 Indonesian Earthquake Deaths

• The significant loss of life from the 2004 Indonesian earthquake resulted from the tsunami it generated.

Subduction of the Indian-Australian Plate

• The December 26, 2004 Indonesian earthquake was triggered by the subduction of this tectonic plate.

S-wave Shadow Zone

• The S-wave shadow zone is attributed to S-waves being unable to traverse the outer core, resulting in areas where these waves do not reach.

Test your knowledge on volcanic activity and its impact on earthquakes in Geology Chapter 12. This quiz explores the connections between magma movements, volcanic explosions, and seismic activity. Perfect for reinforcing your understanding of the geological processes involved in these phenomena.