Earthquake Scales
What does the Richter Scale measure?
The strength or magnitude of an earthquake
What is earthquake technology used for?
seismic monitoring, determining size/location/intensity, alerting/warning, improving infrastructure
What are common hazards after an earthquake occurs? (list at least 3)
collapsing buildings, broken bridges, structures falling, fires, tsunamis, and landslides
What is seismology?
the study of earthquakes and seismic waves that move through and around the Earth
True or False:
The Richter Scale only goes up to magnitude 9.
False.
There is technically no upper limit to the scale. While the largest earthquakes ever recorded have been around magnitude 9.5, the scale itself could theoretically register even larger events. However, a magnitude 10 or higher earthquake is unlikely due to the size of the Earth's fault lines.
What is a seismograph?
an instrument used to record and measure the movement of the Earth's surface, particularly seismic waves generated by earthquakes
Where do earthquakes occur?
Wind-driven waves cause __________ damage compared to tsunami waves.
More
Less
The same amount of
Less
What data does the Modified Mercalli Intensity Scale use?
The observations of damage
How do levitating foundations help protect buildings in the event of an earthquake?
by isolating a building from the ground during seismic activity, which reduces the impact of ground shaking on the structure. This is achieved by using a cushion of air, typically within an inflated airbag, to lift the building a few centimeters off the ground when an earthquake is detected.
What is the difference between foreshock and aftershock?
foreshocks are smaller tremors that occur before the mainshock, while aftershocks are smaller earthquakes that follow the mainshock
True or False:
Hundreds of smaller magnitude earthquakes happen each day.
True.
Magnitudes 2 and below are frequent.
What is the Moment Magnitude Scale?
the measure of an earthquake's strength relative to the distance separated from its fault line
What technologies are used to mitigate (lessen) the effects of earthquakes?
International tsunami warning systems, earthquake-proof structures, limiting development on slopes, and soil drainage
What is it called when the soil is shaken by an earthquake and then acts like a liquid?
Liquefaction
Earthquakes can occur at ______ under Earth's surface.
A. 150 km
B. 250 km
C. 350 km
B. 250 km
Which is preferred for measuring larger earthquakes, the Richter Scale or the Moment Magnitude Scale? Why?
The Moment Magnitude Scale because it provides a more accurate estimate of the total energy released by an earthquake, making it better suited for measuring large earthquakes.
Why not Richter? The Richter Scale, while useful for regional, smaller earthquakes, can become less accurate when measuring larger events, especially if the seismometers are far from the epicenter.
How could acoustic imaging be used to predict earthquakes?
Two instruments are placed about a mile within Earth and approximately 100 ft apart. A sound wave is sent between them, which reveals how the rock is affected by stress.
Why are regions such as the West Coast, East Coast, Hawaiian Islands, and Central America at higher risk of earthquakes?
proximity to plate boundaries/fault lines
9.5, Chile