There have been a couple of minor earthquakes on the island this past month. The first was a 5.2 magnitude quake, on the 14th. The second was a much smaller 4.2 on the 22nd.
I felt the them both, to my surprise.
The 5.2 was enough to show up on the instrument read-outs of the telescope. In fact, the sensors for the positioning of the secondary mirror are sensitive enough to provide a pretty accurate seismograph of the event. Fortunately, there was no lasting effect on the summit facility.
There was a much larger quake in 2006, which caused a considerable amount of damage around the island. This included some severe damage to some of the resorts on the Kona-side of the island, as well as long term shutdowns of many observatories (including Gemini) at summit.
 I actually have no idea how long the links to the facts on these earthquakes last. I'll correct the links if they disappear.
6 months ago