Large earthquakes can give unique signals of their preparation months or even years in advance, which could allow their detection, says a new study published this Tuesday and written by German and Turkish scientists.
The article, published by the journal Nature Communications, analyzes the 7.8 magnitude earthquake recorded last February in Turkey and Syria, which caused thousands of deaths, and indicates that there were signs that began about eight months earlier.
These results add to the accumulated evidence that “at least some large earthquakes present a preparation phase that can be monitored and that has some similarity with theoretical and laboratory models of the failure process,” the authors maintain.
The team led by the University of Potsdam in Germany found that earthquake-affected areas in Turkey and Syria experienced an acceleration in rates of seismic events and an increase in energy release from about eight months earlier, organized into clusters within from a radius of 65 kilometers from the epicenter.
Although the main rupture occurred on a fault and in a region previously identified as having very high seismic risk, preparatory signals occurred both on that area and on a secondary fault, which had previously received little attention.
Some large earthquakes may have a monitorable preparation phase, but due to the large number of variables involved, “with the current state of knowledge, medium-term seismic warning, if possible, remains in the future of seismology,” they emphasize. the scientists. . in the study.
The results highlight the challenges of detecting the preparatory phase and epicenter of large earthquakes, suggesting that a complete understanding of preparatory phenomena would be necessary to develop future warning systems.
More comprehensive monitoring of earthquakes, coupled with long-term seismic records, could improve the ability to recognize earthquake preparation processes from other regional deformation signals.
The authors suggest that the development of seismic warning systems would require more local and regional detection networks, as well as monitoring of secondary faults, which accompany the main rupture faults.
Source: TSF
