Funded by the National Science Foundation (NSF), a team of scientists is returning to Haiti this week to investigate the cause of the January 12, magnitude 7 earthquake there.
The geologists will collect crucial data to assess whether the quake could trigger another major event to the east or west of Port-au-Prince, Haiti's capital.
According to Eric Calais, a Purdue University geophysicist leading the team, said that most aftershocks occur within weeks of the initial quake and that the team urgently needs to get to the site to make a detailed assessment before crucial geological information disappears.
"The big question is instead of small aftershocks, could there be a bigger earthquake coming," Calais said.
"There are many historical examples of an initial earthquake triggering an even larger one along the same or nearby faults. We are concerned for the Dominican Republic, as our preliminary models show that the continuation of the fault in this area is loaded," he added.
The January 12th quake killed an estimated 200,000 people in Haiti, left 250,000 injured and left 1.5 million homeless. Port-au-Prince experienced a magnitude 6 aftershock on January 20.
"The GPS and geological data gathered by this team will provide important insights into the cause of the January 12, 2010, Haitian earthquake, and are essential for evaluating the potential for future earthquakes in the Port-au-Prince area," said Tim Killeen, NSF assistant director for geosciences.
The Haitian Bureau of Mines and Energy and the Civil Protection Agency invited Calais and his team back to the country to examine the fault and advise officials as they prepare to rebuild.
"The government needs scientifically informed advice to decide what to do now and in the future when they start thinking about rebuilding," Calais said.
"We know how to do the calculations that will tell us if the likelihood of other earthquakes along the fault has increased, but we need information that we can only get by going to the field, making direct observations, and taking measurements on the ground," he added.
From GPS measurements at the surface, the team can determine what happened along the fault through its full depth 20 kilometers underground.
Precise measurements of this underground movement are critical for validating models of stress changes that can indicate the potential for, and possible magnitude of, future earthquakes, according to Calais.