Look at this Helicorder from Harrisburg, AR. You can clearly see the shaking going on during the large 7.0 Quake in the Caribbean (Haiti)... not to be confused with Hayti, MO. This is the largest quake to hit that region in history.
To give you a reference point, the below image is a Helicorder display from yesterday when things were not shaking as much. You read a helicorder like a book... with time.
We'll have more on this major Earthquake on Region 8 News.