Can El Paso Texas have earthquakes

Quake with aftermath

Seismologists count around 600 small quakes every five minutes around the globe. However, this number increases dramatically if a severe quake occurs anywhere on earth, the scientists working with Velasco found in their analysis. The number of small earthquakes rose by 37 percent over a period of five hours after a so-called love wave emanating from a severe earthquake had passed through the region concerned. After passing through the so-called Rayleigh wave, the activity even increased by 60 percent.

These two types of waves propagate near the surface of the earth and of all seismic waves emanating from the center of an earthquake they have the greatest destructive power, as they are associated with the strongest ground movements in the horizontal or vertical direction. Scientists are also familiar with P waves and S waves, which usually precede surface waves and have less dramatic effects.

The effects of these surface waves even seem to extend over thousands of kilometers, the researchers were able to demonstrate: For example, the severe earthquake that caused the devastating tsunami in Southeast Asia at Christmas 2004 even triggered tremors in Ecuador. However, scientists do not yet know how the Love and Rayleigh waves promote the formation of small earthquakes over such great distances. “The physical mechanism is still unknown,” explains Kris Pankow, one of the researchers involved. However, it is possible that the waves influence the subterranean distribution of water and thus promote the development of tremors. Other researchers suspect that the waves build up or weaken tensions in the earth's crust and thereby trigger tremors.

Aaron Velasco (University of Texas, El Paso) et al .: Nature Geoscience, online pre-publication, DOI: 10.1038 / ngeo204 ddp / Ulrich Dewald
May 26, 2008