Below are the seismograms of the Tonga and the 2 Aleutian Islands, Alaska earthquakes recorded by Weston Observatory's BC-ESP EQ1 seimograph.

The P wave arrival for the April 15th Aleutian Is. earthquake was at 23:10 UTC.

The P wave arrival for the April 16th Aleutian Is. earthquake was at 06:05 UTC.

The Tonga earthquake's Surface Waves are visible at 01:34 UTC.

The seismograms of the 2 Aleutian Islands earthquakes are very similar because they occurred at approximately the same location.

For more information on these earthquakes, click here.