Il earthquake in southern Calabria of 1783 it is recognized as one of the greatest natural disasters of the 5th century. An intense seismic sequence struck the area of the Strait of Messina and southern Calabria, culminating in XNUMX strong tremors, higher than Mw 5,9, which occurred between February 5 and March 28, 1783.
The earthquake of southern Calabria in 1783
On 5 February 1783 one of the longest and most disastrous seismic periods that have ever occurred in the seismic history of Italy began in Calabria. Between 5 February and 28 March there were 5 very strong tremors and several hundred minor ones. The most violent ones first hit southern Calabria (5 and 6 February), investing the whole area of the Aspromonte and the Strait of Messina, then (7 February, 1 and 28 March) the Strait of Catanzaro, i.e. the area between the gulf of Sant'Eufemia and the gulf of Squillace.
In addition to causing extensive damage - razing the cities of Reggio and Messina and causing tsunamis - the earthquake in southern Calabria of 1783 (also called the Reggio and Messina earthquake of 1783) had lasting effects both on a political, economic and social level.
The first shock lasted 2 minutes, and had Oppido Mamertina as its epicenter. The city was completely razed to the ground and rebuilt after a few years a few kilometers further downstream. Oppido lost nearly 5.000 of its inhabitants. The estimated magnitude of this first, strong seismic event, is equal to 7.1 and describes one of the strongest earthquakes in the Italian seismological history. The quake of 5 February was followed by one on 6 February with an epicenter north of Messina, with a magnitude of 5.9.
Between 5 and 7 February, 949 shocks were counted, followed by a new shock at 20 pm on 7 February, with a magnitude of 6.7 with its epicenter in the current municipality of Soriano Calabro. In the following month, tremors of ever decreasing intensity followed one another, but the strongest were those of March 1, 1783, of magnitude 5.9 with an epicenter in the territory of Polia, and the even stronger one of March 28, of magnitude 7.0 with an epicenter among the municipalities. of Borgia and Girifalco.
The tremors followed one another by moving the epicenter from the south of Calabria going up along the Apennines towards the north of the region. This devastating seismic sequence caused very high damage in a vast area including all of central-southern Calabria from the Catanzaro isthmus to the Strait, and, in Sicily, Messina and its surroundings.
What were the effects and damage caused by the 1783 earthquake?
The earthquake in southern Calabria in 1783 had overall devastating effects on most of the Calabrian territory and in north-eastern Sicily. The damage was incalculable. The cumulative picture of the damages is of extraordinary gravity: the destructive effects on the buildings were accompanied by extensive upheavals of the soils and of the hydrogeological system. Over 180 inhabited centers were almost totally destroyed, including urban centers important for the political-economic and military life of the Kingdoms of Naples and Sicily, such as Messina, Reggio, Monteleone and Catanzaro. According to official estimates, in southern Calabria the victims were about 30.000 out of a population of almost 440.000 inhabitants. The hydraulic disorder caused by the geological upheavals and the hygienic conditions of the period favored one persistent malaria epidemic. In fact, other estimates have calculated that the total number of victims it was around 50.000 Guests.
The numerous and violent tremors also caused massive effects on the natural environment throughout the affected area; some areas of central-southern Calabria were in fact upset in their landscape. The most impressive effects were on the land: there were enormous brakes, collapses, slips, detachments of large portions of land e liquefaction phenomena, such as on the banks of the river Mesima, where hundreds of "vulcanelli" appeared. The effects were particularly shocking on the northern side of the Aspromonte and in the Piana di Gioia Tauro: entire hills collapsed and fell into the valley, in some cases dragging entire towns down to the valley; landslides obstructed numerous streams, resulting in the formation of lakes.
As for the Sicilian territory, it was hit by the earthquake Messina, where the Cathedral was seriously damaged and only the Citadel remained standing. About 650 people died here. The tremors of 5 and 6 February caused a tsunami with large waves that hit large stretches of coast. In particular, the stretch of the Tyrrhenian coast between Scilla and Bagnara Calabra was hit by the catastrophic tsunami.
What do the historical chronicles tell about the earthquake of 1783?
There were many historical testimonies of this tragic event. One report reported:
“Many were wounded, many taken from the ruins, but in the confusion and disorder nothing can be said more certain than having been a true prodigy for those who escaped death. Here is briefly described the unfortunate tragedy that took place in Messina, the destruction of which Edificii exceeds the value of five million, and the devastation and loss of the Furniture, Merchandise, Gold, Silver and Danari was a serious object of fright, and consideration. ".
The testimony of the French geologist Déodat de Dolomieu, who went to Calabria to study the disastrous effects of the earthquake, reports about Polistena, a Calabrian city:
"I had seen Reggio, Nicotera, Tropea ... but when I saw Polistena above an eminence, when I contemplated the piles of stone that no longer have any shape, nor can they give an idea of what the place was ... I felt a feeling of terror , of pity, of disgust, and for a few moments my faculties remained suspended ... "
What was the government intervention and how were the reconstruction works managed after the 1783 earthquake?
The news of the first three earthquakes and the enormous destruction they caused took about ten days to arrive in Naples, the capital of the Kingdom of which Calabria was part of the time. The king of Naples, Ferdinand IV of Bourbon, he decided to intervene by organizing first aid which was followed by a plan for reconstruction.
The severity of the disaster had an enormous impact both on Neapolitan society and on all European culture. Numerous scientists, writers, architects and engineers, both Italian and foreign, were sent to the place to study the phenomena and their effects.
The centers totally razed to the ground were 182. The dimensions of the catastrophe pushed the Bourbon government, and more generally the entire Neapolitan and Calabrian ruling class of the time, to become aware of the need for an extensive and radical reform of the economic and housing system of Calabria. Dozens of villages were abandoned and rebuilt on different sites. The reconstruction of entire cities and towns - such as Reggio Calabria, Messina, Mileto, Palmi - it was designed according to totally new rules and urban plans, which can rightly be seen as one of the first European attempts to introduce anti-seismic legislation aimed at reducing seismic risk.
To intervene quickly he was appointed on February 15 Vicar General of Calabria, with 100.000 ducats for immediate needs.
The damage was so great that in order to find funds the Bourbon government decided to expropriate the ecclesiastical properties of Calabria Ulterior, establishing the Sacred chest, which, however, had an opposite effect to that desired by the Bourbon government, as it increased the landed properties of the nobles who were able to grab ecclesiastical lands by auction.
Following the earthquake, thanks to the Bourbons, the Europe's first anti-seismic regulation, with the establishment of a highly effective construction system, despite some destroyed centers they were never rebuilt. As evidence of this, Johann Wolfgang von Goethe, four years after the event, during his journey to Italy in May 1787, arrived in Messina and told of a city still in ruins with the inhabitants forced to live in the shacks located in the northern part of the city:
“The 30.000 survivors were left homeless; most of the houses having collapsed, and the damaged walls of the remaining ones not offering a safe refuge, a city of shacks was built in great haste, on a vast prairie to the north. "
In addition to the historical point of view, the sequence of 1783 is also very studied by the seismological one, due to its characteristic of very strong events that occurred within a few weeks and very close to each other. From a cultural point of view, many foreign scholars and writers were interested in the event, which in a certain sense opened Calabria to the world.
This series of earthquakes close together in time and space contributes a lot to define the high seismic hazard of Calabria.
