LOST HILLS, CA - MARCH 24:  Pump jacks are seen at dawn in an oil field over the Monterey Shale formation where gas and oil extraction using hydraulic fracturing, or fracking, is on the verge of a boom on March 24, 2014 near Lost Hills, California. Critics of fracking in California cite concerns over water usage and possible chemical pollution of ground water sources as California farmers are forced to leave unprecedented expanses of fields fallow in one of the worst droughts in California history. Concerns also include the possibility of earthquakes triggered by the fracking process which injects water, sand and various chemicals under high pressure into the ground to break the rock to release oil and gas for extraction though a well. The 800-mile-long San Andreas Fault runs north and south on the western side of the Monterey Formation in the Central Valley and is thought to be the most dangerous fault in the nation. Proponents of the fracking boom saying that the expansion of petroleum extraction is good for the economy and security by developing more domestic energy sources and increasing gas and oil exports.   (Photo by David McNew/Getty Images)

El 90% de los sismos (magnitud igual o superior a 3 en la escala de Richter) ocurridos en una región del oeste de Canadá se asocian a la extracción de recursos utilizando la técnica de fractura hidráulica o fracking . Así lo estableció un estudio de la Western University publicado en la revista “Seismological Research Letters”, que investigó 12.289 pozos de fractura hidráulica y 1.236 pozos de agua de desecho situados en una zona petrolífera entre las provincias de Columbia Británica y Alberta, al oeste de Canadá.

En la región del noreste de Columbia Británica, el número de terremotos ha pasado de 20 a 200 al año entre 2002 y 2011, cuando se multiplicaron las actividades de fractura hidráulica.

Fuente: El Mercurio