Poster of the Gulf of Mexico Earthquake of 10 September 2006 - Magnitude 5.8

Tectonic Summary

This earthquake was centered beneath the Gulf of Mexico, well distant from the nearest active plate boundary. Such "midplate" earthquakes are much less common than earthquakes occurring on faults near plate boundaries, and most probably represent the release of long-term tectonic stresses that ultimately originate from forces applied at the plate boundary. This is the largest of more than a dozen shocks that have been instrumentally recorded from the eastern Gulf of Mexico in the past three decades, and it is the most widely felt. The most recent significant earthquake in the region occurred on February 10th, 2006 and had a magnitude of 5.2. We have not associated this earthquake with a specific causative fault.

Earthquakes of this magnitude are unlikely to generate destructive tsunami. No significant tsunami was generated by this earthquake.

The Gulf Coast stress province is characterized by active listric growth faulting. This faulting is steeper near the surface and shallows toward horizontal at depth. The state of stress within the province appears to be uniform with the greatest principal stress vertical and the least principal stress prependicular to the continental margin. The state of stress is probably not associated with tectonic processes but due to sediment loading. The state of stress within the underlying bedrock is unknown.