FAQ - Measuring Earthquakes
Frequently Asked QuestionsWhere can I buy a Richter scale?
Why are there often different magnitudes reported for the same earthquake?
What is moment magnitude?
What are the earthquake magnitude classes?
When was the first instrument that actually recorded an earthquake?
What is a P wave? An S wave?
What does an earthquake look like?
What is intensity? What is the Modified Mercalli Intensity Scale?
What is the difference between intensity scales and magnitude scales?
What is acceleration, velocity, and displacement?
What is spectral acceleration?
What are those beachball figures?
How much energy is released in an earthquake?
What are UTC and GMT (in reference to the time of an EQ)?
What does it mean that the earthquake occurred at a depth of 0 km?
How are earthquakes recorded? How are earthquakes measured? How is the magnitude of an earthquake determined?
What are the different magnitude scales, and why are there so many?
How do you give a Richter magnitude to earthquakes that occurred prior to the scale?
What was the duration of the earthquake? Why don't you report the duration of each earthquake? How does the duration affect the magnitude?
How do seismologists locate an earthquake?
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