User blog comment:Le Rottweiler/Who’s Armagon’s scourge?/@comment-1496755-20150422124329/@comment-1496755-20150424072724

I think "ground zero" can sometimes be used to refer to the epicentrum of an earthquake. And "earthquake" obviously contains "Quake" in itself :P

Besides, the goal of the first part of Q2:GZ is to destroy a huge machine called "tectonic stabilizer". Again, related to earthquakes.

And the overall goal of the mission pack is to destroy the Gravity Well, which also brings some allusions to tectonics and earthquakes ;)