D.O.'s+Earthquake

Hello everybody, these two graphs here, i believe, show the earthquake that happened in the Marina Islands Region on September 28, 2007, at 13:38:58 GMT.

I believe this is the same earthquake because the data wasn't pick up by detectors until about a half hour later than the actual quake. This is okay though because it takes time for the waves to reach the monitor. Another reason that i believe that this is the same earthquake is becuase of the huge spike in the data, and with the earthquake rating at a 7.4 on the richter scale, it's very believable that this is the same quake.