1 Boring Old Man

As for yesterday’s earthquakes, they were in the cards. The Caribbean is laced with seismic faults. Port-au-Prince lies on the Enriquillo-Plantain Garden fault zone. The last cataclysmic earthquake there was in 1751, just after the golden age of the Caribbean Pirates. In the science of plate techtonics, there’s an axiom, in a given region, the magnitude of earthquakes is inversely proportional to their frequency. What that means is that if you live on a fault but don’t have many earthquakes, it’s just a matter of time before you have a big one. An example in the U.S. is Memphis Tennessee where the clock is ticking. And Haiti is such a place. This article was easily located on the Internet and is a testimony to the advances of the earth sciences:

ENRIQUILLO-PLANTAIN GARDEN STRIKE-SLIP FAULT ZONE:
A MAJOR SEISMIC HAZARD
AFFECTING DOMINICAN REPUBLIC, HAITI AND JAMAICA
18th Caribbean Geological Conference
March 24-28, 2008

^{The Enriquillo-Plantain Garden fault zone (EPGFZ) extends from south-central Hispaniola to Jamaica and defines the southern edge of the Gonave microplate. The EPGFZ forms a continuous and prominent geomorphic lineament from the Enriquillo Valley of the Dominican Republic , through the southern peninsula of Haiti , across the Jamaica Passage between Jamaica and Haiti and along the Plantain Garden fault zone bounding the southern edge of the Blue Mountains of eastern Jamaica . The linearity of the fault and its association with en echelon folds, pull-apart basins, and restraining bends indicates that motion is left-lateral and late Quaternary in age. Historical earthquakes indicate that the last major ruptures of the fault occurred in an east to west time-space progression that began in 1751 in south-central Hispaniola and perhaps culminated in the Kingston, Jamaica , event in 1907. Recorded seismicity over the past 40 years is sparse as expected from a fully locked fault plane. GPS-constrained block models with elastic strain accumulation give ~8 mm/year of slip rate on the fault. Since the last major event in south-central Dominican Republic was in 1751, that yields ~2 meters of accumulated strain deficit, or a Mw=7.2 earthquake if all is released in a single event today. The two largest cities within 30 km of the fault zone are Port-au-Prince , Haiti , and Kingston , Jamaica , with a combined population of 3.65 million inhabitants. We present initial results from a paleoseismic study of the Jamaica segment of the EGPGFZ conducted in January, 2008, to determine the chronology of its historic and prehistoric ruptures. Such studies should be considered high priority in Jamaica, Haiti and the Dominican Republic given the seismic hazards posed by the fault.}

 

Well they sure nailed that one! Yesterday’s earthquake in Haiti was a 7.0 with violent aftershocks starting on the eastern end of the fault just like they said it would be. The world just hasn’t quite figured out what to do with these advances in the Earth sciences. Like New Orleans waiting for Katrina, Port-au-Prince has been a sitting duck for what happened yesterday for 250 years.

Port-au-Prince appears to be destroyed from the pictures coming in thus far. The buildings don’t look "damaged." They look "totaled." Right now, the world seems to be responding appropriately with aid streaming towards Haiti from many directions. But after the emergency subsides, there’s going to be a question of rebuilding. Given that Port-au-Prince is mainly a collection of shanty-towns, the world has the opportunity to do something smart. Even though the frequency of earthquakes along that fault is in the range of "rare," does it make sense to rebuild in the same spot? I don’t think so. It looks to me like there are plenty of places in Haiti that do not share the kind of seismic vulnerability as the present location.

Wouldn’t it be a wonderful lesson for the world community to use what we know about earthquakes and help rebuild Port-au-Prince in a more sensible spot? in a more sensible way? The interventions in the AIDS epidemic in Haiti were remarkably successful. Here’s an opportunity to do it again, and further help "Haiti, one of the poorest countries in the world" escape her tragic destiny…