GFZ animated the recent Chilean megaquake and aftershocks sequence. It looks like despite releasing a lot of energy, the earthquakes have not closed the seismic gap. That means the built-up stress wasn't sufficiently released to significantly reduce the seismic hazard in the future.

The Chilean Earthquakes Might Be Just The Beginning

In seismology, silence is never to be trusted as it means that a locked portion of plate is building up stress to release in a catastrophic earthquake. A seismic gap is an area of eerie quiet, where we expect earthquakes and aren't seeing them. Initially we hoped that Chile's megaquake filled one of those gaps, reducing stress in the region, but now it looks like only a third of the locked section slipped.

It appears that while the central portion of the stuck plate broke and slipped, both the northern and souther sections didn't budge. This means that the stress was not fully released along the gap, and even potentially increased along the boundary between the slipped and locked sections. Further observations will determine how the stress redistribution has impacted the region, but for now it looks like the seismic risk of megaquakes in the southern or northern portions of the gap is still very real.

The Chilean Earthquakes Might Be Just The Beginning

Image credits: GFZ. Science Daily has an English-language summary of GFZ's initial findings. Note that this is INITIAL RESEARCH and we won't have anything substantial to report for a while.