Detecting & Mapping EQs (Lessons 3 & 4) Practice

Front

What is the 12-hour time equivalent of 15:31?

Back

3:31 PM

Front

What does a longer lag time between P-Waves and S-Waves indicate about the distance from the epicenter?

Back

The seismograph is farther from the epicenter.

Front

What is the term for the point on the Earth's surface directly above the focus of an earthquake?

Back

Epicenter

Front

If the first P-Wave arrives at a station after 120 seconds, what does this indicate about the distance to the epicenter?

Back

The epicenter is relatively far from the station.

Front

What are P-Waves?

Back

Primary waves that are the first to arrive during an earthquake, traveling through solids and liquids.

Front

What are S-Waves?

Back

Secondary waves that arrive after P-Waves and can only travel through solids.

Front

How do seismographs work?

Back

They measure the motion of the ground during an earthquake.

Front

What is the focus of an earthquake?

Back

The point within the Earth where the earthquake originates.

Front

What is the difference between the epicenter and the focus?

Back

The epicenter is the point on the surface directly above the focus.

Front

What is the significance of the lag time between P-Waves and S-Waves?

Back

It helps determine the distance to the earthquake's epicenter.