Haiti earthquake - the aftershocks

[GliderGuider]

Aftershocks can be devastating, and I've never seen so many, and so consistently strong, as with this quake. To get a better feeling for this I plotted a time series of the shocks and their magnitude. The time scale covers the 17 hours from the initial quake to the most recent recorded aftershock. The time axis is in UTC.



They had a really hard night.

[tridim]

1. Is there a fault line running through Haiti?

Or is this type of quake caused by something else?

[WeDidIt]

2. Yes, it runs straight through the island of Hispanola along the Southern edge

and is the reason the island is so mountainous.

[catbyte]

7. The Caribbean is a hotbed of seismic activity

The largest city in Martinique, St. Pierre, was devastated in 1902 when Mt. Pelee erupted. Over 30,000 people died. Everyone thinks of the Pacific when you're talking volcanoes & earthquakes, but the Atlantic is dangerous, too. Several plates meet in the Caribbean--the Atlantic, Caribbean, and South American Plate. The Canary Islands are another danger zone which, if it blows as predicted, could generate a tsunami that would demolish the eastern seaboard of the US.

My thoughts are with those poor souls today--Haiti just cannot catch a break... :cry:



Diane

Anishnabe in MI

[csziggy]

3. At least two faults run through/by Haiti

Major Tectonic Boundaries: Subduction Zones -purple, Ridges -red and Transform Faults -green

[GliderGuider]

4. Yes, there is.

The quake appears to have occurred along the Enriquillo-Plantain Garden Fault, a virtually immovable rock that runs from Montego Bay in Jamaica to the southern part of the island of Hispaniola, which Haiti shares with the Dominican Republic. That vertical fault is pushed by the Caribbean Plate, a land mass that moves about 20 millimeters (about 1 inch) east each year.

The plates have been pushing against the fault since a major quake in 1760. On Tuesday, the plates got the fault to move. The total slip could amount to 250 inches, or 20 feet (the accumulated movement since 1760). That's a lot.

[tridim]

5. 20 feet. Wow.

Thanks for the info you three.

[FarCenter]

6. Strike slip fault that it inside the Carribean Plate

Haiti is south of the Carribean plate boundary with the North American plate.

But per the following map, there is a strike slip boundary at just above 18 degrees north latitude at the left side of the map. That fault goes through Port au Prince.

[blm]

8. After the Northridge quake we were hit with swarms of high intensity aftershocks...

they really were quite unnerving, and went on for months at various levels. The violent shaking of this Haiti quake is on par with the violence of Northridge. The key differences in the deathtolls are the time of day and the building standards.