There are many aftershocks that occur after the Mainshock.
The Mainshock did little additional damage in this area.
The largest earthquake in a series is called the Mainshock.
UPDATE 17:22 UTC: The second earthquake(Mainshock) shook the area approx.
Hours later a much stronger and also shallow 5.2 Mainshock occurred.
Update 15:18 UTC: Since the Mainshock, we have noticed 9 major aftershocks.
Update 13:30 UTC: Since the Mainshock we have noticed already 4 aftershocks with a Magnitude greater
than 4!
The Mainshock was followed by a series of aftershocks,
with 14 of M≥5.0 in the first 24 hours.
This earthquake is an aftershock in the
same faulting area than the March 11 Mainshock, but at a totally diffrent location.
If an aftershock is
larger than the first earthquake then we call it the Mainshock and the previous earthquakes in a sequence become foreshocks.