The magnitude-7.2 earthquake that killed at least 1,941 people in Haiti last weekend occurred on the same fault line responsible for the massive 2010 quake — which is why a leading seismologist at the University of Miami warns the country should brace for more quakes sooner than later.
After the 2010 Haiti earthquake — that killed some 200,000 people, mostly in the capital city Port-au-Prince — UM scientist Falk Amelung saw a grim seismic future there. That's because satellite interferogram imagery showed the quake ruptured only one segment of the Enriquillo-Plantain Garden fault-line system, leaving considerable stress on adjacent segments (the Enriquillo fault line extends west to Jamaica).
That fault had not fractured since the 18th century, so Amelung and his UM team predicted another section would break relatively soon.
They were unfortunately proved right last Saturday — by a Haiti earthquake that was actually stronger than 2010's.
“We should not be at all surprised," said Amelung, a professor of marine geosciences at UM's Rosenstiel School of Marine and Atmospheric Sciences.
"One domino falls after the other, essentially," he added, pointing to other examples around the world such as the North Anatolian Fault in Turkey.
Amelung says the one wrinkle is that the earthquake domino that fell last weekend was not right next to the one that broke in 2010, "as we would have expected." What ruptured instead was a segment further to the west on Haiti's southwestern Tiburon Peninsula, and area that includes the hard-hit city of Les Cayes.
Either way, Amelung says that leaves at least three more sections of the fault system now prone to snap in the coming years. They stretch from just south of Port-au-Prince — which raises concern of another strong temblor affecting the heavily-populated capital — to the tip of the Tiburon Peninsula.
“We know now this is a high-hazard fault, and we now have a pretty good idea which parts of the fault are at highest risk," said Amelung. "So I would concentrate seismic retrofitting efforts on that very precarious area.”
By that, Amelung means making structures more earthquake resilient. Haiti’s government has long neglected that remote southwest region — and what retrofitting has been done there is more often for hurricanes, not earthquakes (the peninsula was devastated by Hurricane Matthew in 2016).
Amelung said, going forward, the region faces an awful double dilemma.
“What do you for a hurricane? You build a roof which is very heavy, so it doesn’t fly away," he said. "And that’s just the worst thing to have in an earthquake. It’s not earthquakes that kill people, it’s the buildings.”
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