Earthquakes Review Quiz

Chapter 8: Earthquakes Review Quiz 20 points Total (1 pt. each ) 1) When an earthquake occurs, energy radiates in all directions from its source. The source is also referred to as the ________. A) inertial point B) epicenter C) focus D) seismic zone 2) ________ have the highest velocities. A) Primary waves B) Secondary waves C) Surface waves D) Refracted S waves 3) Major earthquakes are often followed by somewhat smaller events known as ________. A) aftershocks B) foreshocks C) tremors D) hyposhocks 4) The ________ magnitude scale is a measure of the energy released. It does not directly measure the extent of building damage. A) Gutenberg B) Reid C) Mercalli D) Richter 5) The instrument that records earthquake waves is termed a ________. A) polygraph B) thermograph C) seismograph D) barograph 6) The position on Earth's surface directly above the earthquake source is called the ________. A) epicenter B) inertial point C) focus D) seismic zone 7) The mechanism by which rocks store and eventually release energy in the form of an earthquake is termed ________. A) elastic rebound B) seismic rebound C) fault displacement D) stress fracture 8) The lithosphere is defined as ________. A) a rocky layer having a relatively uniform chemical composition B) a rigid layer of crustal and mantle material C) a rocky layer composed mainly of crustal rocks D) a plastic layer composed mainly of mantle material 9) Approximately how much more energy is released in a 6.5 Richter magnitude earthquake than in one with magnitude 5.5? A) 3000 times B) 3 times C) 30 times D) 10 times 10) The Mercalli Scale is a scale from ________. A) 1 to 12 that rates the energy required for faulting to occur B) 1 to 10 that rates the energy released by an earthquake C) I to XII that rates the structural damage due to an earthquake D) I to X that rates the total energy released during the main quake and all aftershocks 11) The distance between a seismological recording station and the earthquake source is determined from the ________. A) earthquake magnitude B) intensity of the earthquake C) length of the seismic record D) arrival times of P and S waves 12) Which one of the following best characterizes tsunamis? A) They cause the land to ripple and oscillate. B) They are faster than seismic surface waves. C) They have relatively small amplitudes compared to their very long wavelengths. D) They are easily seen at sea but are lost in the swell and breaking waves along a coast. 13) The record of an earthquake obtained from a seismic instrument is a(n) ________. A) seismograph B) seismogram C) time-travel graph D) epigraph 14) ________ refers to the tendency for a foundation material to lose its internal cohesion and fail mechanically during earthquake shaking. A) Slurrying B) Liquefaction C) Motion slip D) Seismoflowage 15) P waves ________. A) propagate only in solids B) are faster than S waves and surface waves C) have higher amplitudes than do S waves D) produce the strongest ground shaking 16) The Richter magnitude of an earthquake is determined from the ________. A) duration of the earthquake B) intensity of the earthquake C) arrival time of P and S waves D) amplitude of the largest seismic wave 17) Most of our knowledge about Earth's interior comes from ________. A) drill holes B) volcanic eruptions C) seismic waves D) examination of deep mine shafts 18) The average composition of the oceanic crust is thought to approximate that of ________. A) granite B) basalt C) peridotite D) iron 19) The average composition of the continental crust most closely approximates that of ________. A) granite B) basalt C) peridotite D) iron 20) The Earth's magnetic field originates by ________. A) weak electrical currents associated with hot, rising, mantle plumes B) magnetic mineral grains in the inner core C) weak electrical currents associated with fluid motions in the outer core D) magnetization of oxygen and nitrogen atoms in the atmospheric ozone layer by solar radiation