This seems to be controversal subject after looking it up a bit. A few people say that yes, the moon does influence the quakes while a group of scientists say that no, it's not possible. I have to say, I'm tending to agree with the group that think that the moon does have an influence. Everytime we have a swarm of earthquakes here in Chirstchurch, it always within a few days of a full moon. Infact, based on the previous months swarm, I had already assumed that today would be the day the next swarm hit and that turned out to be true with a nice big 5.1 shallow shake early this morning and a series of shallow aftershocks following. The usual argument given back as to why it can't be true is that the moon is too small to have an influence...however it has an effect on the tides and weather, so why wouldn't it create a pull on the ground as well?