I have lived in Earthquake country all my life. I have been in a multitude of small quakes as well as several large ones. There's no way I want to risk my reef by using all glass.
My house sits on top of two colliding continental plates, and the region is many years overdue for a massive quake. You can learn more about it
here. Anyone using all glass for a large tank on the Left Coast is taking a serious risk. IMO, anything over 200g that is all glass has a very high probability of a blow out. Even a small quake can get water moving beyond the structural integrity of an aquarium. In my case, I would have about 9,000 lbs. shifting back and forth.
And earthquakes don't just shake. They roll like a wave on the ocean. I have seen it with my own eyes, and the stresses created by the roll are way beyond the shaking. When the Northridge Quake hit, I was living in Beverly Hills and many miles from the epicenter.
I watched the floor in my home roll like a 3 - 4 foot wave was going through it. I couldn't believe what I was seeing. On the bottom floor, everything was fine. On the second floor, absolutely everything was destroyed. No way a glass fish tank would have survived.