The unusually high magnitude of Tuesday’s quake for this region is part of the reason it has likely caused enormous damage to Haiti.
The quake forced that project to shut down, and its sponsor had to make millions of dollars in payments for damaged buildings.
Rough estimates suggest that any useful quake forecast method demands precursors that will prove correct 98 per cent of the time.
The steel framing of a multi-storey building is a system of beams, girders or trusses, and columns, designed to carry all the gravity loads of the structure and to resist wind and earth-quake forces.
