Scientists claim, the earthquake which struck Christchurch New Zealand was bullseye, as it hit the city. The quake was recorded to be a 7.0 magnitude earthquake and it was the first tremor to hit the city, but later a 6.3 magnitude shaker struck and toppled most of the buildings in the Christchurch. This is the sole reason why there were so many casualties and property damage in the city, because it was a direct hit.
Christchurch is a shallow city, in other words, the city has a very low foundation and the water table begins just few meters below the surface. As a result the liquid and mud below the surface mix and it makes it look like a giant quicksand.
The quake on Tuesday made the water and mud shake violently thus started to suck in objects which were on the surface. Some 100,000 buildings have sustained major damage in Christchurch, and around 400 people are missing or pronounced dead.