Understanding Earthquake Effects and Measurements

The video explains the difference between earthquake magnitude and intensity, highlighting that magnitude is a measure of energy released, while intensity varies by location. It discusses factors affecting intensity, such as magnitude, distance from the hypocenter, and local soil conditions. The video also covers the history and use of ShakeMaps, which illustrate intensity variations. Examples from past earthquakes demonstrate how these factors influence damage. Finally, it emphasizes the importance of safety measures during earthquakes.

What are the three main factors that control seismic intensity?

• Magnitude, distance from the epicenter, and local rock and soil conditions

• Magnitude, weather conditions, and time of day

• Distance from the epicenter, time of year, and local vegetation

• Magnitude, local wildlife, and distance from the ocean

How is earthquake magnitude similar to the wattage of a lightbulb?

• Both determine the color of light

• Both are related to the amount of energy released

• Both affect the temperature of the environment

• Both are influenced by the time of day

What does a ShakeMap illustrate?

• The color of the sky during an earthquake

• The intensity of ground shaking at different locations

• The temperature changes during an earthquake

• The speed of wind during an earthquake

What scale is used to reflect the effects of an earthquake in ShakeMaps?

• Richter Scale

• Beaufort Scale

• Modified Mercalli Intensity Scale

• Fujita Scale

How does increasing earthquake magnitude affect shaking intensity?

• It increases shaking intensity everywhere

• It has no effect on shaking intensity

• It decreases shaking intensity everywhere

• It only affects shaking intensity at the epicenter

What pattern does a ShakeMap for a magnitude 7.0 earthquake in Mozambique illustrate?

• A linear pattern

• A spiral pattern

• A bullseye pattern

• A zigzag pattern

How does earthquake depth affect ground shaking intensity?

• Deeper earthquakes cause more intense shaking at the surface

• Shallower earthquakes cause more intense shaking at the surface

• Depth has no effect on shaking intensity

• Deeper earthquakes cause less intense shaking at the surface

What geological condition amplified shaking during the Loma Prieta earthquake?

• Solid rock

• Bay Mud

• Desert sand

• Mountainous terrain

What phenomenon occurred in the Marina District due to weak ground conditions?

• Tsunami

• Hurricane

• Volcanic eruption

• Liquefaction and fires

What immediate actions should be taken during an earthquake to ensure safety?

• Stand still and wait

• Drop, Cover, and Hold On

• Run outside quickly

• Climb to a higher place