As many of you may have heard, a fairly large earthquake devastated Haiti earlier this week.
The variables just didn’t work out for this, hitting an impoverished country such as Haiti, but the worst being that the epicenter of this earthquake was a measly 15km from Port-au-Prince, making the 7.0 magnitude quake all the more devastating.
As mentioned, the main reason for such a disaster is the proximity to the epicenter, and taking a look at the tectonic plates around the globe, the Dominican Republic lies directly south of the plate boundary between the Caribbean and North America plates. That is, the North American plate (correct me if I’m wrong) is subducting beneath the Caribbean plate, however the Caribbean plate is so small in relation because it itself is being subducted beneath the South American plate. So basically it’s getting squeezed out and in millions and millions of years, will be completely subducted.
When people think of subduction zones, they’re pretty much thinking of a cut-and-dry scenario, where one plate goes under another, and that’s that. However, depending on it’s orientation, there are several places along a plate boundary where they don’t meet head on, and you get what’s called ‘strike-slip’ faulting, where instead of one plate going underneath the other, they slide past. Combine that with subduction, and you have an area like that in the Caribbean. Eventually, the area that’s undergoing strike-slip will eventually subduct, but at the moment (geologically speaking), this small area slides past. Now, even my explanation is pretty simple in relation to what’s really going on, but I’ll leave it at that. Hopefully countries worldwide will come to the aid of the tiny nation of Haiti!
Below is a better picture of Haiti in relation to the plate boundary from Google Earth.