MEXICO EARTHQUAKE QUESTION April 5, 2010

This is a question for general discussion for anyone who is interested in the subject matter.

Question: What might the low magnitude earthquakes in the list below have been telling us, if anything?

2010/04/04 22:40:41 32.128 -115.303 10.0 7.2
2010/04/04 22:34:51 32.280 -115.274 10.0 3.3
2010/04/04 09:36:25 32.227 -115.276 4.1 3.4
2010/04/04 07:51:35 32.137 -115.314 0.2 3.2
2010/04/04 05:05:07 32.137 -115.318 0.1 3.3
2010/04/03 23:03:47 32.167 -115.296 32.6 4.4
2010/04/03 20:49:04 32.263 -115.302 33.2 3.2
2010/04/03 19:38:51 32.290 -115.285 12.0 2.7
2010/04/03 03:47:59 32.229 -116.589 6.0 3.3
2010/03/31 09:20:26 32.354 -115.229 6.0 4.2

The top earthquake is the main Mexico earthquake that occurred on April 4. But the others in the list go back as far as March 31. I did not see any earlier than that from a quick check.

Not being a geophysicist I am wondering what the significance of those earlier earthquakes might have been. My guess would be that the fault zone was getting ready to fracture. And the earlier earthquakes were signaling that it was about at the breaking point.

One theory could propose that strain might have been spreading from where the fault zone was locked. And it was causing those other low magnitude earthquakes to occur.

Another theory could propose that the low magnitude earthquakes allowed the fault zone to slip in such a manner that strain was abruptly transferred to where the actual earthquake occurred. And that caused the earthquake to be triggered, perhaps weeks or more before it would otherwise have occurred.

Perhaps both theories, or neither, are correct.