A radar strapped to the belly of a NASA jet crisscrossed the island of Hispaniola this week taking three-dimensional snapshots of the island’s surface that scientists say will allow them to create precise topographical maps, according to the Jet Propulsion Laboratory near Pasadena. Flight plans call for multiple observations of the Caribbean island’s faults this week and in early to mid-February. “What happens sometimes is there’s one big earthquake and then later—weeks, months, sometimes years afterward—you see the second earthquake is triggered,” Paul Lundgren, principal investigator at JPL for the Hispaniola overflights, told the Pasadena Star-News. “We want to have observations in place in case that occurs.”
The radar works by sending pulses of microwave energy from the belly of the aircraft to the surface of the Earth 41,000 feet below. It can sense swelling and tensions that may reveal new stresses on the grinding boundary between two tectonic plates that crash into each other in the eastern Caribbean. Radar focused on the Enriquillo-Plantain Garden Fault, which runs along Haiti’s southwestern peninsula just 15 miles from Port-Au-Prince, according to the JPL news statement. Seismologists are also concerned about the Septentrional Fault on the other side of the island in the Dominican Republic. The two faults are parallel, roughly on the north and south sides of Hispaniola and the nearby Caribbean island of Jamaica. “Because of Hispaniola’s complex tectonic setting,” Lundgren said in the news statement, “there is an interesting in determining if the earthquake in Haiti might trigger other earthquakes at some unknown point in the future, either along adjacent sections of the Enriquillo-Plantain Garden fault that was responsible for the main earthquake, or on other faults in northern Hispaniola, such as the Septentrional fault.”
The likelihood of an earthquake might be raised in that area, but that isn’t the same as predicting an earthquake. “It’s a very deep research field,” Lundgren told the Pasadena Star-News. “There’s a lot of uncertainty.” JPL researchers have been conducting flyovers with NASA’s Gulfstream III research aircraft at various seismically-active spots on the globe since February 2009, the Star-News reported, but it was only after Haiti’s devastating quake and aftershocks that Hispaniola was added to the itinerary.
Lungren said the upcoming flights, and other NASA will conduct in the coming weeks, months and years, will help scientists better assess the geophysical processes associated with earthquakes along large faults and better under the risks.
Posted originally by Southern California Public Radio at http://www.scpr.org/news/2010/01/30/jpl-seeks-warnings-even-bigger-haitian-quake/