Satellite-based data has recently shown that human activity caused the several Texas earthquakes in 2012. Researchers discovered that the main reason behind it was oil and gas excavations, which disturbed the Earth’s underground activity.
According to the latest research from the scientists, five major Texas earthquakes were caused by man. The process of exploiting gas and oil from the ground requires injections of wastewater. This method led to major unnatural convulsions, in areas where there was no tectonic activity, which Texas residents eventually experienced as significant earthquakes.
Between 2012 and 2013, no less than five such earthquakes occurred in Texas. As the statistics show, one of them reached a considerable magnitude, namely 4.8. This is one of the most powerful quakes that ever occurred in the state.
For their analyses, researchers investigated the holes in the ground dug for the water supplies. They observed that those located in the East of the state were shallow in comparison to those in the West. The shallow excavations had nothing to do with the man-caused earthquakes, scientists say. The Texas earthquakes were caused by the deep ones, as the information provided by the satellite shows.
Researchers noted that the earthquakes didn’t necessarily occur in the proximity of the wells. The pressure put on the ground propagated miles away, even as far as fifteen miles. Another important observation is that with man-caused quakes, the earth is not pushing towards the surface. Under this conditions, the most accurate pieces of information on the underground pressure also come from satellites.
The underground activity was visible for one year, and after that, the earthquakes stopped. This is good news for residents, but specialists say that there was still some activity going on underground for the next year and a half. Specialists observed that the movement completely stopped the moment when there were reported low rates of oil and gas exploitation in the area.
The satellite information was provided by the Japanese Advanced Land Observing Satellite. Professor William Ellsworth is one of the authors of the study on earthquakes produced by human activity. In a press release, he talked about the importance of his team’ s research:
“Our research is the first to provide an answer to the questions of why some wastewater injection causes earthquakes, where it starts, and why it stops.”
The new study helps scientists monitor human activity and its effects on the environment. It was published in Science, on September 22.
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