Here is a seismograph from a mobile station on Santorini. You can see normal earthquakes, which come from rocks cracking, and then you see a fuzzy waveform, which looks like volcanic harmonic tremors to me, which may indicate the movement of magma.
Here is a stronger vibration of some kind from another seismometer on Santorini.
Article on Santorini volcano: http://www.volcanodiscovery.com/view_news/4601/The-Greeks-take-serious-the-swarm-earthquakes-at-Santorini-!.html
The latest article on rising co2 levels and sea water temperatures rising: http://www.volcanodiscovery.com/view_news/4715/Santorini-volcano-Greece-strong-seismic-swarm-continues-scientist-speak-out-finally.html
And finally the media mention the constant earthquakes: http://greece.greekreporter.com/2012/01/29/earthquakes-rattle-southern-greece-non-stop/
A live view of a seismometer on Santorini. http://bbnet.gein.noa.gr/plots/SAP2.html
And another live view on Santorini. Looks like Harmonics: http://bbnet.gein.noa.gr/plots//SANT.html
And here is the live state of the Ionosphere: http://www.ips.gov.au/HF_Systems/6/5
In my opinion, Santorini Volcano in Greece is about to have an eruption, because today co2 levels have spiked, and two seismometers are showing what appears to be volcanic harmonic tremors. I could be wrong in my determination of what kind of waveform this is, for a generator could cause this kind of waveform. But I am of strong opinion that these above wave form is harmonic in nature.
Oddly, there are a great many strange earthquakes, some 4 mag plus throughout Greece, and lot's of 3 mag plus events. I don't know what to think of this.
All I can say is that magma is on the move, according to my educated guess work.
Another note, is that at the time of this writing 2 am PST, the ionosphere is at a high, at 16 Mhz. There is an interaction between the Ionosphere and the behavior of the ground, according to a good many scientists.
Click the provided links and explore and compare.