PF+LIGO+Post-Activity+Assessment

Using the ruler tool in Google Earth, I calculated the distance from the epicenter of the earthquake to LIGO to be 10940.03 km.
 * 1. Use Google Maps (or Google Earth—your pick) to calculate the distance from the quake’s epicenter to LIGO.**


 * 2. Calculate the seismic wave speed twice, once for each of the LIGO plots shown.**


 * Seismic Y Graph**: In order to find the wave speed, you have to divide the distance by the amount of time it took from the earthquakes inception to when it was detected at LIGO. It occurred at 3:50:40.80, and hit LIGO at approximately 4:12. This means that it took about 21 minutes 20 seconds, or 1280 seconds to get from the epicenter to LIGO. So: **(10940km)/(1280s)= 8.546875 km/s.***


 * Seismic Z Graph**: Again, you have to divide the distance (10940km) by the amount of time it took to be detected by LIGO. It occurred at 3:50:40.80, and hit LIGO at approximately 4:09. This means it took about 19 minutes and 20 seconds, or about 1160 seconds. So:
 * (10940km)/(1160s)= 9.43103 km/s**

I noticed that when you compare the Y and Z graphs, you can see that high points that occur at times on the Y graph have corresponding low points on the Z graph. I found this interesting, but I'm not sure what the relationship between the two graphs is.
 * 3. Comment on any difference you see between the LIGO plots, and between the wave speed estimates obtained using each plot.**

I also found it interesting that the same earthquake was detected at different times by different detectors at LIGO. Also the Z graph detected it for a longer period of time. It is strange because the two detectors are in close proximity to each other, yet the one of them detected something much longer than the other. I can't think of a reason for that to happen.