Earthquakes seem to give no respite throughout the world: Venezuela, Colombia, Indonesia... and now, although to a lesser extent, Granada. The province has recorded 348 tremors from August 14 to the morning of Monday the 17th, as confirmed by the National Geographic Institute (ING). In addition, a new 4.8 earthquake has once again shaken the area with four aftershocks so far. But why is there so much seismic activity in the province?
Seismologists remember that the Granada basin is one of the most "trembling" regions of the entire Iberian Peninsula and is also where the strongest earthquakes have occurred throughout history. The National Seismic Network defines the area as "very dangerous" because it has "many faults capable of generating an earthquake." The explanation behind the phenomenon would be its location in the Betic mountain range (the youngest mountain system in the country) and the convergence between the African and Eurasian plates.
But it doesn't stop there; Granada is located on the rise to the Sierra Nevada, the highest mountain in the Iberian Peninsula (remember Mulhacén, which measures 3,842 meters). Scientists have found in the Sierra Nevada remains of marine sediments that were deposited there about 8 million years ago, when that area was much closer to sea level. Some of these remains are today at around 1,830-1,980 meters above sea level.
This means that the Sierra Nevada has been rising little by little for millions of years. In the last 8 million years, some areas of the massif have risen at least 2,000 meters. And that process still continues, at a speed that can reach 1 millimeter a year. But there is something important: mountains do not grow continuously; The ground accumulates tension for a long time and is suddenly released through earthquakes or earthquakes.
Silent earthquakes
In Spain there are billions of earthquakes a year, but few are felt. The former president of the Illustrious Official College of Geologists (ICOG), Manuel Regueiro, pointed out in the past for 20minutos that "90 percent of earthquakes are not felt by people." It is a natural activity and, according to the expert, it is good that small earthquakes occur to prevent "energy from accumulating and leading to a larger earthquake."
Still, it is worth remembering that earthquakes cannot be predicted, at least not with precision. Geology allows us to identify the most dangerous areas and study the faults capable of generating movements, as happens in Granada and other areas of the Betic mountain range such as Málaga, Almería, Huelva, Cádiz, Murcia and Alicante.
The history of earthquakes in Granada
The oldest earthquake recorded in the IGN occurred in 1431 south of Granada and caused extensive damage to the Alhambra, and the most devastating occurred in 1884 with 839 fatalities. However, experts add that the strongest earthquakes recorded since the beginning of instrumental seismology, in 1857, have originated in deep areas. Among them, the Granada earthquake of 1954, with a magnitude of 7.8, and the one registered in 2010, with a magnitude of 6.3, stand out.
