Canie - I thought that there was energy being released before the quake started, but I know nothing about geophysics, so perhaps Don knows something?

Don...thanks for the additional information. I've been quite curious about this phenomenon since I heard about the event here in Washington in 1999. I became more interested when I heard that prior to the great quake in Chile that one of these slow quakes had occurred. I know that the Cascadia Subduction Zone has been spring loading for it's next event for about 301 years now and I am learning as much as I can about the processes that shape this area.