Boy Scout Motto: Be Prepared Figure 9.85 is a prediction made by the USGS about the probability of a 6.7 or greater earthquake in the San Francisco Bay Area. Currently it stands at 62% before 2032. BEFORE AN EARTHQUAKE 1.Identify potential hazards in your home and begin to fix them. 2. Create a disaster - preparedness plan. 3. Create disaster kits for everyone in your home. 4.Identify your building’s potential weakness, and 5. Protect yourself during the shaking AFTER THE EARTHQUAKE 6. Check for injuries and damage. 7. When safe, continue to follow your disaster - preparedness plan. FIGURE 9.85 Earthquake Prediction by the USGS Map courtesy of the USGS FIGURE 9.84 Earthquake awareness book for people living in California (USGS LINK) Source: USGS LIVING IN EARTHQUAKE COUNTRY SUMMARIZED FROM THE BOOK “ PUTTING DOWN ROOTS IN EARTHQUAKE COUNTRY, BY THE USGS
KEY WORDS Aftershock: a smaller earthquake occurring after and in the same area as the larger main earthquake. Body wave: seismic waves that travel through the Earth; P and S waves. Earthquake: violent ground shaking, resulting from movement's within the crust of the Earth, as along a fault, volcanic action, or general rebound of depressed crustal rocks. Elastic rebound: theory that explains the origin of earthquake energy, whereby rocks under stress deform without breaking (thus storing up energy), until the elastic limit is reached and they break, releasing the stored energy. Epicenter: the point on the Earth's surface that is directly above the focus, or point of origin, of an earthquake. Fault: a fracture within the Earth's crust, along which there has been displacement (movement). Fault line: a line created where the plane of a fault intersects the Earth's surface, either vertically, or horizontally. Fault plane: extensive flat surface along which there has been displacement (movement). Fault scarp: a step in the land surface due to vertical movement along a fault, or topographic expres sion of relative upward movement along a fault. Fault zone: an area broken by numerous individual faults. Focus: the point along a fault plane, at which an earthquake begins; the point of origin of an earthquake. Foreshock: a smaller earthquake occurring before the larger main earthquake. Inertia: the tendency of an object to resist changes in motion. Inertial mass: with respect to a seismograph -- the stationary object acting as a point of reference in the determination of ground movement initiated by an earthquake. L wave: a seismic surface wave, whose motion is side - to - side horizontal or parallel to the Earth's surface; usually the third seismic wave to reach a seismic station; also known as Love or Long wave. Liquefaction: phenomenon where saturated, or partially saturated sediment, acts like a liquid when stressed, as when shaken by an earthquake. Long wave: a seismic surface wave, whose motion is side - to - side horizontal or parallel to the Earth's surface; usually the third seismic wave to reach a seismic station; also known as Love or L wave Love wave: a seismic surface wave, whose motion is side - to - side horizontal or parallel to the Earth's
You've reached the end of your free preview.
Want to read all 50 pages?