Living in Earthquake Country Concept Maps

Overview Evidence from past earthquakes can help us predict the amount of damage to expect from future earthquakes. 1. Earthquakes may occur repeatedly in the same locations. a)Earthquakes occur along faults at plate boundaries. Earthquakes relieve strain that accumulates over time because of plate motion. Earthquakes occur along patches of planar faults – they are not just a single point but have lengths and widths. 2. Earthquakes release energy in the form of seismic waves, which cause shaking. a)Shaking spreads out from the entire rupture patch, not just the epicenter. b)A single earthquake produces several different types of seismic waves that have different effects. 3. Scientists measure both the amount of energy released in earthquakes (magnitude) and the severity of shaking at particular locations (intensity). a)The shaking that is felt (the intensity) depends on three factors; magnitude, distance and depth, rock type. Higher magnitude earthquakes result in greater intensity shaking. Soft rocks amplify shaking while locations on hard bedrock shake less. The closer you are to an earthquake, the greater the intensity. Distance is measured both horizontally and vertically (because earthquakes occur at depth). b)Scientists examine the average time between ruptures as a useful measurement for assessing the risk the fault presents. The more time that passes between repeated surface ruptures on a single fault, the larger the earthquake. Smaller earthquakes cause less damage each time but occur more often. Areas that experienced strong shaking in the past are likely to experience strong shaking in the future. 4. Shaking may result in damage in the form of structural failure, liquefaction, and changes in landslides. a)Earthquakes may cause damage that disrupts people’s lives.

Earthquakes may occur repeatedly in the same locations. Earthquakes release energy in the form of seismic waves, which cause shaking. Shaking may result in damage in the form of structural failure, liquefaction, and changes in landslides. Evidence from past earthquakes can help us predict the amount of damage to expect from future earthquakes. Earthquakes occur along faults at plate boundaries. Scientists measure both the amount of energy released in earthquakes (magnitude) and the severity of shaking at particular locations (intensity). Living in Earthquake Country Lesson 1Lesson 2Lesson 3Lesson 4Lesson 5Lesson 6 Earthquakes relieve strain that accumulates over time because of plate motion. Earthquakes occur along patches of planar faults – they are not just a single point but have lengths and widths. Shaking spreads out from the entire rupture patch, not just the epicenter. A single earthquake produces several different types of seismic waves that have different effects. The shaking that is felt (the intensity) depends on three factors; magnitude, distance and depth, rock type. Scientists examine the average time between ruptures as a useful measurement for assessing the risk the fault presents. Higher magnitude earthquakes result in greater intensity shaking. Earthquakes may cause damage that disrupts people’s lives. Soft rocks amplify shaking while locations on hard bedrock shake less. The closer you are to an earthquake, the greater the intensity. Distance is measured both horizontally and vertically (because earthquakes occur at depth). Areas that experienced strong shaking in the past are likely to experience strong shaking in the future. The more time that passes between repeated surface ruptures on a single fault, the larger the earthquake. Smaller earthquakes cause less damage each time but occur more often. Lesson 7