What type of earthquake did Haiti have in January 2010?

Answer 1

On the 12th of January 2010 at 21:53:10 GMT / 16:53:10 local time, a strike slip fault known as the Enriquillo-Plantain Garden fault, forming part of the transform boundary between the Caribbean and North American plates slipped due to the stresses that had accumulated within the crust causing a magnitude 7.0 earthquake.

In more detail:

The Enriquillo-Plantain Garden fault has been locked for approximately 250 years. As such, stresses have accumulated in the earth's crust over this time, causing energy to be stored in the form of elastic strain (like that in a compressed spring). Ultimately this stress has exceeded the shear strength of the crust in the fault zone causing a sudden brittle failure or rupture. This in turn has caused movement and a sudden release of the stored elastic strain energy in the form of seismic waves (as well as heat and sound).

The rupture of the fault zone was approximately 65 km (40 miles) in length with an average slip of 1.8 m (5.9 ft). Analysis of seismometer data showed that the seismic waves produced by the movement on the fault had amplitudes of up to 4 m (13 ft).

The epicentre of the Earthquake was very close to the Haitian capital city Port-au-Prince and was at very shallow depth causing significant damage to infrastructure and caused the collapse of a large number of buildings.

It is estimated that approximately 230,000 people were killed in the Earthquake and more than 250,000 people injured.

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