High aftershock risk for Haiti in next 30 days: USGS

The capital Port-au-Prince was hit by two fresh aftershocks on Friday, 10 days after the initial 7.0-magnitude quake killed at least 75,000 people and left half a million others homeless.

"The aftershock sequence of the magnitude-7 earthquake that struck near Port-au-Prince, Haiti, on January 12, 2010, will continue for months, if not years," the USGS warned in a bulletin on its website.

"The frequency of events will diminish with time, but damaging earthquakes will remain a threat."

There was only a three percent chance of another 7.0-magnitude quake in the next 30 days but there was a 25 percent chance of at least one 6.0-magnitude tremor and a 90 percent likelihood of at least one 5.0-magnitude quake.

Any aftershock above 5.0-magnitude will be widely felt and "has the potential to cause additional damage, particularly to vulnerable, already damaged structures," the USGS said.

Nearly 50 aftershocks have rocked Haiti since the initial earthquake, the strongest being a 5.9-magnitude tremor on Wednesday.

The strongest of Friday's new shocks was of magnitude 4.4, the USGS said.

The geological fault responsible for the January 12 quake is part of a seismic zone located between the American and Carribbean tectonic plates.

(c) 2010 AFP