MOSCOW, April 29 (RIA Novosti) – Almost 50 tremors have shaken Mexico’s northern state of Nuevo Leon this year as a result of large-scale fracking for shale gas in the region, the Global Post reported Tuesday.
Since the beginning of the year, a record 48 earthquakes have been registered in Nuevo Leon, while there were only two tremors in the same period last year, statistics from Mexico’s National Seismological Service showed.
The surge in seismic activity is connected with hydraulic fracking by Mexico’s government oil monopoly Pemex in the Burgos and Eagle Ford shale deposits, according to local experts.
“The one thing that has changed is the introduction of fracking. There is no other explanation,” Ruperto De La Garza, an expert from the environmental and risk consultancy Gestoría Ambiental y de Riesgos, told the Global Post.
His findings, published March 22, indicated a correlation between seismic activity and fracking in Northern Mexico.
“The final result is the dislocation of the geological structure which, when it is pulverized, allows the trapped gas to escape. When the chemicals are injected “and the lutite particles [sedimentary rock] break down, the earth shifts,” IPS news agency quoted Ruperto De La Garza as saying.
The connection between seismic activity in northeast Mexico and human actions that modify the rock layer were also revealed in the study “Sismicidad en el estado de Nuevo León” published by the Autonomous University of Nuevo León in January.
Even though the Nuevo Leon tremors haven’t exceeded a magnitude of 4.3, they still caused damage to some buildings. But experts believe that fracking has much more serious impacts.
Fracking could weaken rock structures and make them more vulnerable to the effects of potent quakes, said Aaron Velasco, an earthquake expert at the University of Texas El Paso, according to the Global Post.
The surge in tremors has resulted in anti-fracking protests all over northern Mexico. Local residents have demanded a ban on the method until more is known about its potential environmental impact.
Fracking, or hydraulic fracturing, has recently gained wide global attention as a method of oil and gas extraction. Its benefits are controversial, since the process involves injecting liquids with carcinogenic chemicals into rock formations to release gas. The chemicals stay in the ground and can pollute soil and groundwater.
