Labs and other Homework

Guiding Questions:
How can you locate an earthquake's epicenter?

Hypothesis:
You locate an earthquake's epicenter by finding the center of three different cities to see where the crossing point is- the edge or point where they cross is the epicenter.


Analyze & Conclude:

1. Observe the three circles you have drawn. Where is the earthquake's epicenter?
The earthquake's epicenter is somewhere between Mississippi and Alabama.

2. Which city on the map is closest to the earthquake's epicenter? How far, in kilometers, is this city from the epicenter?
The city closest to the earthquake's epicenter is Mobile which is in Alabama. It is approximately 100 km.

3. In which of the three cities listed in the data table would seismographs detect the earthquake first? Last?
The closest city city to the epicenter is Houston Texas, the next closest city to the epicenter is Chicago Illinois, and the farthest city from the epicenter is Denver Colorado.

4. About how far from San Francisco is the epicenter that you found? What would be the difference in arrival times of the P waves and S waves for a recording station in San Francisco?
San Francisco is about 3,000 km away from the epicenter. The difference of arrival times of the P waves and S waves for recording station is 4 minutes and 40 seconds.

5. What happens to the difference in arrival times between P waves and S waves as the distance from the earthquake increases?
The difference in arrival times between P waves and S waves increases as the distance from the earthquake increases.

6. When you are trying to locate an epicenter, why is it necessary to know the distance from the epicenter for at least 3 recording stations?
It is necessary to know the distance from the epicenter for at least 3 recording stations because we need to find the crossing points of all three. If you have two circles, then you will have two possible points of earthquakes.


MORE TO EXPLORE:

When I looked at figure 18 (earthquake risks in the U.S) I wasn't quite sure what my earthquake risk is, but in my opinion, the point is not about the highest risk, I assume this is the white gray color. When I looked at the map of earth's Lithospheric plates, I could assume that the cause of the earthquake in this area is in compression of the North and South American plates.

Research the city where you come from to see if there are any Earthquakes which have occurred in your area and if so when and how often? What magnitude are they?
The last recent earthquake that happened in Serbia was in Kraljevo in November the 3rd. It happened about 2 hours after midnight and it was 5.4 degrees by the Richter magnitude scale. The epicenter was 10 kilometers North from Kraljevo in a village called Vitanovac, unfortunately 2 people died during the earthquake. The strongest earthquakes in Serbia was not with the epicenter in Belgrade, but they were located mostly in central Serbia and their average magnitude (the strongest one) is approximately 5.7 degrees of the Richter magnitude scale. The first one was detected in 1893 with the epicenter in Sviljanac which was 5.7 degrees.