Does climate change affect earthquake activities in the world?

The Sangre de Cristo mountain range was formed in the plains of the St. Louis Valley in southern Colorado over millions of years. These mountains bear the name of an earthquake fault that still causes earthquakes in that region to this day. A recent study suggests that the melting of glaciers thousands of years ago may have increased the frequency of earthquakes in the St. Louis Valley due to the relief of stresses on the seismic fault.

Geologists, in general, do not link the phenomenon of climate change to the movement of seismic faults or Earth’s plates that extend to deep depths beneath the Earth’s crust.

However, a recent study published by the scientific journal Geology, which specializes in geological sciences, observed evidence that the waves of global warming experienced by the planet Earth, similar to what is happening at the present time, may actually affect seismic activities in the world. Researchers warn that as global temperatures continue to rise, other glaciers may begin to melt, causing seismic activity like what is happening in southern Colorado.

Geological researcher Sean Galen from Colorado State University and one of the study participants said in statements to the American Scientific website, which specializes in scientific research, that “areas that are witnessing a decline in the size of glaciers or changes in water cycles above active seismic faults may, at some point, be exposed to due to increased seismic activities.

During 25 million to 28 million years ago, the Earth’s interior in the western region of the North American continent began to split, which led to the formation of the Rio Grande Fault. As the Earth slowly split, the San Luis Basin began to decline and the Sangre de Cristo Mountain mass rose. Until the vertical distance between the highest point and the lowest point reached 9.2 kilometers. Then, about 2.6 million years ago, the Earth’s temperature dropped, and snow formed on the tops of the Sangre de Cristo Mountains. With the process of snow formation reaching its peak 20 thousand years ago, valleys with twisted shapes began to form containing deposits of snow aggregate, in the fastest expansion of its kind of snow masses on the surface of the Earth.

Researchers say that increasing or decreasing the size of surface masses can put pressure on the Earth’s crust. For example, when mountains are formed, the Earth’s crust is compressed down by the excess weight, and then returns to flattening again when these mountains are eroded by weather factors and erosion. This can lead to The process known as Isostatic Rebound results in limited seismic activities, and perhaps this is the reason behind the earthquakes that still occur in the Appalachian mountain range in the eastern United States from time to time. Galen and the study team wonder whether melting snowpack due to global warming might have a similar effect on seismic activity.

The research team hypothesizes that melting snow can change the magnitude of pressures on ground faults and accelerate the frequency of earthquakes in the short term due to the relief of pressure on the earth’s crust.

The Scientific American website quoted Galen as saying that it is easy to develop computer models to measure such seismic activities, but testing this theory in nature is the gold standard for proving it, noting that there is concrete evidence that confirms the validity of this theory on the ground, such as the Wyoming-Teton fault in the United States. United States, where seismic activities increased in that region with the melting of the snow cover of the Yellowstone Mountains. Jessica Job, an earthquake expert at the US Geological Survey, confirms that the latest study actually proves that this phenomenon is more common than scientists previously thought, adding that “scientists are trying to find a link between climate and seismic activities,” noting that the Yellowstone Mountains are considered… A great area to do this because there are weather and earthquake databases in that area, which is not the case in many cases.

In order to prove the validity of this scientific hypothesis, Galen created a computer model that bears the same features as the Sangre de Cristo Mountains, including twisted valleys containing glacial moraines in addition to ground faults that divide the Earth’s crust, in an attempt to determine the timings and locations of earthquakes that occurred in that region in certain eras. prehistoric.

The researchers used high-resolution satellite images to draw clear maps of these geological changes, and then made comparisons between the results of the computer model and the geological nature of the region on the ground. According to the new theory, the research team concluded that the presence of glaciers was “shackle” the system of ground faults in the region and prevent earthquakes. As these rivers began to melt 20,000 years ago, the pressure on the Earth’s crust decreased and the frequency of earthquakes in that region increased five-fold.

Geologist Eric Leonard of the University of Colorado agrees with the hypothesis that the melting of even the smallest glaciers in the Sangre de Cristo mountain ranges could have a significant impact on the activities of geological faults, but he says that the age of the faults that cut through the earth’s crust in that region is not determined, which affects… The ability to accurately know the timing of earthquakes that occurred. Galen acknowledges the necessity of relying on other precise mechanisms to know the chronology of earthquakes in that region with greater accuracy, and thus to know the impact of climate change and the melting of glaciers on the occurrence of earthquakes more clearly, but he is confident that the evidence reached by his scientific team confirms the truth of the scientific hypothesis about the impact of climate change. On seismic activities, he says, “We have compelling evidence here.”