A big rupture that size can place MASSIVE stress on other huge formations. If one of them rips, we could get a cascade effect: very large earthquakes occuring with increasing frequency.
In the Pacific Northwest, the Cascadia Subduction Zone can produce earthquakes of the size of 9.0 to 10.0 ... and one is due for that area, too... (according to the pattern of the previous ones... ooops...).
AND..., this is nothing new for our present time, as it's been going on like this for hundreds of years, even thousands of years... so it's a very regular type of cycle.