As the earths crust begins to cool, just like an egg, the internal pressures will build. Not only are we headed to cooling but that cooling will create other pressures with which the earth must deal with. If not a little at a time, it would happen very fast and violently without warning. we have been calm for way to long. Even the St Andrus fault is over due by 20 years.
Our context of normal may have been to short a time span to know what is normal for the earth.
Umm...... San Andreas. And faults are not like trains, they really don't have a schedule.
While your comment is technically true, there is a periodicity to the quakes along most major faults. The San Andreas is one of the most heavily researched fault zones in the world and here is a more recent paper dealing with the subject. Pallet Creek is another well researched paleoseismic site along the San Andreas.
This proposal aimed to extend the paleoseismic record on the Big Bend section of the southern San
Andreas fault with information from trenches excavated across the fault at Cuddy Valley. However,
stratigraphy was poor at the Cuddy Valley site, and resources were shifted to the existing paleoseismic
site at Frazier Mountain, about ten miles east of Cuddy Valley. Trenches excavated across a
transtensional stepover at the Frazier Mountain site have provided evidence of at least eight earthquakes
in the last 1000 years, with an average recurrence interval of about 122 years. One trench, T23, was
excavated east of the depocenter containing the evidence of these events in hopes it would expose older
stratigraphy and thus an earlier earthquake record. However, it was located in another syncline and
depocenter that contained similar young sediments to those exposed in the previous trenches. Three to
five earthquakes were recognized in the trench but were the same young earthquakes already identified
elsewhere at the site. Although the trench did not extend the earthquake record into the past, it did provide
information to clarify the detailed structure of the stepover.
http://earthquake.usgs.gov/research/external/reports/G08AP00014.pdf