Which natural disaster uses the Richter scale to measure strength? Earthquake true Tornado false Tsunami false Hurricane false Single How much bigger is a magnitude 8 earthquake compared to magnitude 7 one on the Richter Scale? 1x bigger false 10x bigger true 100x bigger false 1000x bigger false Single Why do earthquakes usually occur at plate boundaries The rock on the edges of tectonic plates is soft and gives in easily to various pressures false Rock in environments near tectonic plate boundaries experience great stress true The boundaries between tectonic plates have been seismically active for millions of years false Rock in environments near tectonic p late boundaries experience little stress false Single What are solid rock fragments that are ejected during a volcanic eruption? Lahar false Magma false Pyroclastic Material true Silica false Single Which of the following is the correct order of the effects of a large volcanic eruption? Some of the sun's energy is blocked; gas and ash are released; the result is a cooling effect. false Gas and ash are released; some of the sun's energy is blocked; the result is a cooling effect. true Carbon dioxide causes the climate to warm; some of the sun's energy is blocked; the result is a cooling effect. false Gas and ash are released; some of the sun's energy is blocked; the result is a warming effect. false Single The movement that occurs during mass wasting is caused by what? Wind false Gravity true Ice  false Water  false Single An angle at which sediment will not slide down a slope is called: Angle of Reuse false Angle of Repose true Slope Angle false Reposing  false Single Why is decreased vegetation a factor that can cause mass wasting? When plants are removed from the ground, the spaces they leave are filled with heavier rocks. false Decreased vegetation is not a factor that causes mass wasting. false Vegetation stabilizes soil at the surface, and their roots anchor soil under the surface. true Decreased vegetation is not a factor that causes mass wasting. false Single Soil and rock act as giant sponges because they are full of tiny pores and cracks that hold underground water. These small pores allow the water to infiltrate and collect underground. Rain and snowmelt that infiltrates the ground is called backflow false groundwater true sponge gate false infiltrate false Single The geological layer, consisting of underground caverns and porous layers of sand, gravel, or bedrock, where groundwater flows, is called zone of saturation false aquifer true the water table false surface water false Single