Is there precedent for a string of near-major earthquakes in this or any other region? (I concede that a 6.6 feels major if you're in the middle of it, but with the logarithmic scale used, it's a long. long way off a 7.5, say). And if so, what happened thereafter? With Italy being a volcanic region, often a fact overlooked since it's been quiet for a generation (Vesuvius in 1944), should we expect some magma movement and eruptions which are now overdue?
It's a good question and I'm not sure if anyone would have a definitive answer. You could say that in some cases the quakes have been releasing tension that had built up but in this case the suggestion has been more of a case of one quake leading to instability in another part of the fault region in turn leading to further quakes.
I did wonder about the potential link to volcanic activity but have a hunch it would be a tenuous one. However I would be very surprised if the experts are not checking...just in case.
In the immediate future I would expect to see the aftershocks continue for a few days but whether there are more quakes in this area of magnitude - I've no idea. It's what makes the situation so fascinating but equally so potentially deadly.