The 1977 Gioia Tauro harbour (south Tyrrhenian sea, Italy) landslide-tsunami: Numerical simulation

On July 12th, 1977, waves 5 m high hit the harbour of Gioia Tauro, provoking relevant damages on facilities and infrastructures, but fortunately no casualties. The source was supposed to be a submarine mass failure, ranging 5 million m3 and occurring in very shallow water at the heads of a canyon just in front of the port. The sliding mass cut a cable at 600 m depth, meaning that it travelled more than 15 km far from the source. In this work we reconstruct the hypothesized mass failure, compute the slide dynamics and simulate the generated tsunami through numerical modelling. The results obtained fit well with the observations, strengthening the hypothesis of such a landslide as the source for the 1977 tsunami. This event can be considered as paradigmatic of a category of coastal hazards: small submarine landslides occurring close to populated coasts may pose considerable risk, even if only at a local scale.