The earthquakes which hit Mexico took hundreds of lives, and they were a natural disaster, but seismological activity can be caused by people as well. Some of the common ways to trigger an earthquake are mining activities and building dams, according to the data collected by the scientists.

In recent years, however, the earthquakes have been more frequently caused by extracting oil and fuel from oil shale rock fragments by fracking, Seismological Research Letters scientists report. Human activity produces only weak ground shaking, but sometimes, more powerful earthquakes can happen as consequences. For example, the dam building in China caused a 7.9-magnitude quake in 2008.

Scientists led by Myles Wilson from the Durham University, Great Britain, created the database called “HiQuake,” which is the updated version of the already existent database. The project has been started and financed by the Netherlands’ company for gas and fuel exploitation called Nederlandse Aardolie Maatschappij, which owns a large gas field near the city of Groningen.

The researchers rummaged through the projects published in the science magazines, reports from congresses, news related to this particular field, government reports, and articles in media. As a result, their database currently has around 730 examples of people-caused seismological activities. Besides the causes mentioned above, the other things which can trigger earthquakes are geothermal drilling for exploiting heat from the ground, building skyscrapers and nuclear weapon explosions.

Wilson stated: “All human projects affect the forces which influence Earth’s core, by adding or detracting mass. Because of that, we shouldn’t be surprised that the Earth reacts to those changes and sometimes the reaction is an earthquake.”