Earthquakes can be attenuated by groundwater
Researchers from EPFL and the Ecole Normale Supérieure in Paris have found that the presence of pressurized fluid in surrounding rock can reduce the intensity of earthquakes triggered by underground human activities like geothermal energy production. Around 100,000 earthquakes are recorded worldwide every year, but not all are naturally occurring. Some of the weaker ones are triggered by human activity underground - this is referred to as induced seismicity. Researchers from EPFL's Laboratory of Experimental Rock Mechanics (LEMR) and the Ecole Normale Supérieure in Paris have just completed a study into the role of fluids in the propagation of induced earthquakes in an effort to decipher the underlying mechanisms. Their findings include the extremely counterintuitive discovery that highly pressurized water in the vicinity of an earthquake tends to limit - rather than increase - its intensity. These results were published today . Induced earthquakes can be the result of activities like mining, gas and oil extraction, toxic waste or CO 2 storage, and the construction of tunnels and dam reservoirs.
