Friuli Italy 1976 (CAR)
On Thursday 6th May 1976, at 21:00 local time, an earthquake of moment magnitude 6.5 and focal depth of 21 km occurred in the Friuli region (northeastern Italy).
The earthquake’s epicentre (46.38°N, 13.27°E) was 20 km north of Friuli’s capital city of Udine (population 100,000), in the hilly rural area between the small towns of Buia, Gemona, not far from the borders with Austria and Slovenia.
The earthquake was preceded by a foreshock of M4.6 one minute earlier and took place during a particularly warm evening when most people in the region were out of doors.
An area of 4800 km2 embracing nearly 100 communes with a population of half a million was affected, with 18,000 dwellings (housing 32,000 people), large number of schools, town halls, churches and factories being destroyed.
In the USGS EXPO-CAT database it is estimated that during this earthquake 349,000 people were exposed to intensity VII or higher, of which around 34% were in rural areas.
Human casualties were 965 dead and 2400 injured.
Epicentral intensity was assessed at I0 = X (on the MSK intensity scale) for the triangular area enclosed by the villages of Trasaghis and Osoppo and the town of Gemona (where 2.6% of the combined population was killed). In Udine (intensity VI-VII) more than 50% of all the dwelling units were damaged.
Many aftershocks (especially those of May 9 and May 11 with magnitude 5.1 and 5.2 respectively) and heavy rains that set in from May 7 caused additional damage making the homes of another 157,000 people temporarily uninhabitable.
The region begun immediately a gradual process of recovery, but 4 months later, on September 11 and 15, four significant aftershocks of magnitude 5.4 to 6.0 caused additional damage and a combined 16 deaths and several more injuries.
The number of homeless which had decreased since May from 189,000 to 45,000 because of the repair of less badly damaged buildings, swelled again to more than 70,000. By April 1977 all the needed temporary housing units had been constructed and the homeless moved from coastal hotel rooms that were requisitioned during the winter. In total 70,000 people occupied these temporary housing units, dropping to 50,000 a year later.
The direct cost of this earthquake was estimated at 3.47 billion US$ (circa 2% of the GDP of Italy in 1976) and 1.28 billion US$ in indirect losses. The losses were further inflated by the September 1976 aftershocks.
In Utsu's catalogue 3700 people injured is mentioned.
Over 50% of the deaths occurred in the villages: Gemona del Friuli, Osoppo and Forgaria.
989 deaths is also often quoted.
The earthquake was preceded by a foreshock of ML=4.5 occurring just one minute before the main shock. Many people were outdoors at the time of occurrence as it was a warm evening.
Number of buildings collapsed or to be demolished in the 8 worst affected municipalities, out of a total of 16,250 ispected buildings.
The FRED database (Friuli earthquake damage database) contains 76,000 inspected buildings (incl. the destroyed buildings).
939 people perished in the wreckage of 17,000 collapsing houses; the homes of 32,000 people were totally destroyed.
20,880 living units to be newly erected according to the reconstruction plan for the 95 worst affected communes (out of 113 affected communes).
189,000 homeless people at the peak of the crisis, as follows:
The homes of 32,000 people were totally destroyed, but many aftershocks and heavy rain pulverized the already badly damaged buildings still further, making the homes of another 157,000 people uninhabitable.
The number of homeless decreased by the beginning of September 1976 to 45,000 as most of the less badly damaged houses got repaired, but swelled again to more than 70,000 with the occurrence of the M6.1 aftershock on September 15, 1976.
By the end of 1976, 41,000 people lived in camping trailers, evacuation centres and tents, while another 25,000 lived in newly erected prefabricated houses, temporary shelters and railway cars.
Thus new housing had to be created for 66,000 people.
From Table 3.4 in Geipel's book. 466 million US$ in direct losses to the productive sector, 2804 million US$ in damage toi dwellings, public installations and 201 million US$ in hydrogeologic damage.
Losses increased further (20-30%) after the Sept 11 & 15, 1976 aftershocks.
From Table 3.4 in Geipel's book. 1279 million US$ indirect losses to the productive sector.