High risk of further aftershocks

HAITI can expect more aftershocks in coming weeks, and while the usual pattern suggests they will become weaker and less frequent, another one as strong as yesterday’s jolt is certainly possible, scientists say.

The battered nation has felt more than 40 aftershocks since the January 12 quake, with yesterday’s temblor the strongest, with a magnitude of 6.1. These events are a sign the land is adjusting to “the new reality of the rock layers,” said Bruce Pressgrave, a geophysicist with the US Geological Survey.

Eric Calais of Purdue University, who has studied earthquake potential in the region, said aftershocks could continue for several weeks and that another jolt as strong as yesterday’s would not be surprising.

“They will be less and less frequent, but large ones can still strike,” he said.

So buildings are still at risk, especially those already weakened, he said.

Julie Dutton, a USGS geophysicist, agreed that more aftershocks are probable and that another magnitude-6.1 event was certainly possible.

Paul Mann of the University of Texas said it’s hard to predict whether another sizeable quake is in the future, since “we are dealing with a natural system that is very complex.”

Calais also said that the fault zone responsible for last week’s quake extendsin to the neighbouring nation, the Dominican Republic.

It’s “somewhat of a concern to us” that the Haiti quake may have raised the chances for a quake there.

The two countries share the island of Hispaniola.