Falling levels of groundwater table could trigger earthquakes, a new study suggests. The last decade has seen a huge surge in the exploitation of underground water resources for both commercial and private use. Reckless pumping of groundwater by citizens and industrial enterprises can lead to an increase in seismic activities in the Andreas Fault Region.
There has been a steep rise in the number of minor earthquakes in the last 30 years. Some earthquakes are also triggered by the prolonged dry season.
A latest finding which has been published in the Journal Nature suggests that falling groundwater levels forces the Earth’s crust to spring upwards. The reason for this phenomenon is that water is heavy and when it is no longer in the ground, the pressure changes, leading to seismic tremors.
The study published in the journal Nature on Wednesday states that groundwater loss in the Central Valley due to the agricultural requirements puts pressure on the Andreas Fault, increasing the risk of Earthquakes in the region. The Central valley produces one quarter of America’s food output. The study however did not predict when the earthquake can happen.
It is common knowledge that the groundwater levels has been dropping dangerously. The primary cause for this is the pumping of water from deep bore wells for irrigation purposes. In the last 150 years 160 Cu.km of water has been utilized through irrigation, pumping for industries and evaporation in this region. The expanding population is exacerbating the situation where the groundwater utilization is faster than the replenishment rates.
The study has for the first time attributed a human factor to the earthquakes. The human factor is becoming more and more dominant. The more you deplete the groundwater, the more you push the fault towards failure.
The study is led by Colin Amos of Western Washington University. The researchers used GPS Data to analyze tiny movements in the Central Valley and the adjoining mountains. The researchers found that mountains closest to California’s thirsty Central Valley grew at a faster rate than ranges further away at a rate of 1 to 3 millimeters a year. This adds up to more than a foot in the last 150 years.