Roger, thanks for your response.

Actually an extra thanks since your post shows that there is still so much to learn. "Too difficult and too expensive" means we don't know for sure, but you should buy our explanation.

Message to all lurkers and active posters on this board.... keep an open mind because what you now believe may not be fact. You have conditioned your mind to believe that which you have been told. Earthquakes cannot be predicted, therefore, we do not actually know why they occur.

It is easy to believe what you have been told. Living in a seismically active area, it seems less and less likely that the common "facts" are actually true.