Assignment 10/ Copy down the notes, cornell style. I have put stars next to the notes which are usually highlighted Answer the Concept Checks on a separate sheet of paper to be turned in when you return your notes After you finish taking notes, begin working on the Project at the end of the notes. You will have time the next class to FINISH the project.

Destruction from Earthquakes Chapter 8, Section 3

Seismic Vibrations The damage to buildings and other structures from earthquakes depends on several factors. The three factors include the intensity and duration of the vibrations, the nature of the material on which the structure is built, and the design of the structure. The damage to buildings and other structures from earthquakes depends on several factors. The three factors include the intensity and duration of the vibrations, the nature of the material on which the structure is built, and the design of the structure. Engineers have learned that unreinforced stone or brick buildings are the most serious safety threats during earthquakes Engineers have learned that unreinforced stone or brick buildings are the most serious safety threats during earthquakes Liquefaction – loosely consolidated sediments are saturated with water and turned into a liquid that is not able to support buildings Liquefaction – loosely consolidated sediments are saturated with water and turned into a liquid that is not able to support buildings

Seismic Damage Liquefaction – Niigata, Japan 1964 Ground Shaking – Loma Prieta, CA 1989

Concept Check When does liquefaction occur? When does liquefaction occur?

Tsunamis Tsunamis – A large water wave caused by seismic waves Tsunamis – A large water wave caused by seismic waves A tsunami triggered by an earthquake occurs where a slab of the ocean floor is displaced vertically along a fault A tsunami triggered by an earthquake occurs where a slab of the ocean floor is displaced vertically along a fault A tsunami also can occur when the vibration of a quake sets an underwater landslide into motion A tsunami also can occur when the vibration of a quake sets an underwater landslide into motion A tsunami can travel across the ocean at a speed of km/hr A tsunami can travel across the ocean at a speed of km/hr When the wave enters shallow coastal waters, it will slow down and begin piling on top of itself to reach a height sometimes greater than 30 meters When the wave enters shallow coastal waters, it will slow down and begin piling on top of itself to reach a height sometimes greater than 30 meters

Tsunamis

Tsunami Travel Time to Honolulu

Indonesia Tsunami – 2004

Concept Check At what point does the tsunami gain the most height? At what point does the tsunami gain the most height?

Other Dangers The greatest damage to structures is from landslides and ground subsidence, or the sinking of the ground triggered by vibrations The greatest damage to structures is from landslides and ground subsidence, or the sinking of the ground triggered by vibrations The violent shaking can cause water and gas lines to rupture The violent shaking can cause water and gas lines to rupture Fire is also a threat, as witnessed by the large-scale destruction of San Francisco when their gas and electric lines were cut along with the water lines needed to put out the fires Fire is also a threat, as witnessed by the large-scale destruction of San Francisco when their gas and electric lines were cut along with the water lines needed to put out the fires

Other Dangers Fire – San Francisco, 1906 Landslide – Turnnagin Heights, Alaska, 1964

Predicting Earthquakes The goal of short-range prediction is to provide an early warning of the location and magnitude of a large earthquake The goal of short-range prediction is to provide an early warning of the location and magnitude of a large earthquake Methods for short-range predictions of earthquakes have NOT been successful Methods for short-range predictions of earthquakes have NOT been successful Long-range predictions give the probability of a certain magnitude earthquake occurring within 30 to 100-plus years Long-range predictions give the probability of a certain magnitude earthquake occurring within 30 to 100-plus years Seismic gap – an area along a fault where there has not been any earthquake activity for a long period of time Seismic gap – an area along a fault where there has not been any earthquake activity for a long period of time Scientists don’t yet understand enough about how and where earthquakes will occur to make accurate long-term predictions Scientists don’t yet understand enough about how and where earthquakes will occur to make accurate long-term predictions

Probability of Earthquakes Along the San Andreas Fault

Shaking Hazard for Southern California