Hi Randall. Not being a geologist or seismologist by training I can only repeat what I have been told and to some extent what I have seen and felt.

The San Andreas fault is a transform fault. It’s division between the Pacific Plate and the North American Plate. They slide past one another and when a large rock gets in the way it stops sliding at that point while at the same time the areas further out from the locked point continue to move as well as the area above and below and in front of the locked point as well as to the rear of the locked point. In other words everything keeps moving except for the point that the fault is locked. If it takes a lot of movement over long periods of time before the rock shears we get a major quake. If it only take a little bit of stress and effort to move past that point then we get a small quake.

The San Andreas fault in the area of San Juan Bautista is always moving because there is not much to stop it from moving. The same thing applies to the Calaveras fault in the Hollister area.

To my way of thinking it’s when two plates trying to move past, under, over, or thought one another meet little resistance in the way of small rocks instead of large rocks we get an increase in creep and to some extent will continue to do so until it meets a large resistance that tries to prevent in from moving. It continues to remain that way until it reaches the point that enough force is reached that will overcome that resistance.

Keep in mind this is how I see what the cause of most quakes are. I know there has been some quakes in the past that to date the cause is not really known, or understood, however these quakes are the real deep quakes. Take Care…Don in creepy town

• Cause Of Quakes