The Holy Grail of earthquake science is the ability to predict with some certainty 3 important characteristics of an anticipated earthquake: its time, place, and magnitude. Earthquake science has made great strides in recognizing earthquake-prone regions, calculating earthquake probabilities and anticipating the potential for damage. In the right hands, this information has proved invaluable in saving lives and property.
The only element lacking for true prediction is the ability to determine the exact time of an earthquake. Due to the chaotic nature of the physics behind rock fracturing, it is unlikely that an earthquake will ever be predicted with precision well in advance. The best that can be hoped for is a short-term warning based upon a signature precursor that heralds the actual earthquake. This kind of warning may be never more than on the order of minutes or seconds, but even that kind of margin may well separate life from death.
For now engineers and planners armed with current earthquake science, building to modern codes and prepared to respond after earthquakes strike, can give earthquake-prone areas a good chance of withstanding all but the strongest earthquakes as well as provide the necessary resiliency to quickly recover from them.
It is in those areas where earthquake awareness is lacking or structures fail to meet minimum safety standards that devastation and tragedy awaits. Haiti is the latest victim, and this poor country has been doubly victimized by both a failure to correctly anticipate the imminent danger, and to mitigate against it.
According to Nature Magazine, at the 2008 Caribbean Geological Conference, Paul Mann of the University of Texas at Austin presented a paper entitled “Enriquillo-Plaintain Garden Strike-Slip Fault Zone: A Major Seismic Hazard Affecting Dominican Republic, Haiti, and Jamaica.” The abstract alone was chilling in its prescience:
…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.
It’s important to note that this paper didn’t make a prediction that went unheeded. It presented a scenario that could have occurred the day after the conference or 50 years from now. The sad reality is while the correct response should have been to initiate a multi-billion dollar investment in improving the infrastructure of Haiti, as the poorest country in the Western Hemisphere, it could hardly feed its own people much less undertake the necessary capital improvements, and certainly not within a two-year window.
But it is also true that neighboring Jamaica and the Dominican Republic dodged a bullet. Our understanding of the EPGFZ was not sophisticated enough to rule out that the 1/12 earthquake wasn’t going to devastate Kingston instead. Billions saved by not taking mitigation measures will hopefully be spent to restore Haiti, and maybe even to improve it.
Looking forward, will we continue to see this pattern replayed again and again:
- 2003: an earthquake levels Bam, Iran killing over 26,000 people.
- 2004: the second-largest earthquake ever recorded generates a tsunami that sweeps across the Indian Ocean and kills 228,000 people.
- 2005: an earthquake destroyed an area the size of Belgium in northern Pakistan and Kashmir, killing 75,000 people.
- 2008: a 7.9 earthquake in the Sichuan Province of China killing 70,000.
We have the ability to determine where earthquakes are likely to occur. We have the ability to determine where buildings and infrastructure are likely to be severely damaged or destroyed. At this point, we still apparently lack the will to devote the necessary expenditures to protect the world’s poorest and most vulnerable.
While it may be easy to dismiss these catastrophic disasters as just a fact of life in the developing world, bear in mind that geologists predict a similarly-sized magnitude 7.0 earthquake will eventually strike the midsection of the U.S. along what is known as the New Madrid Fault. Over 1 million people in Memphis, Tennessee and St. Louis, Missouri are living in the same kinds of unreinforced masonry structures that have become deathtraps in Haiti.