Natural "disasters"

There is a saying in Chinese, "天灾人祸" combining two types of disasters, natural and man made.

It seems the formal type is much more emphasized when earthquakes occurs, but I wonder if the latter is the main culprit for casualties. The recent earthquake in New Zealand where there isn't a single death, may suggest it is.

Earthquakes don't really kill directly. Most mammals just felt the shake. Most trees don't fall. Most fishes and birds might not even be affected.

Then, how did human beings get killed or injured in earthquakes? I think the recent earthquake in New Zealand quite clearly suggests that earthquakes don't really kill human beings, but many times it was the unsafe/unnatural structures that were designed and built by human beings that killed and injured the victims.