The August 24th quake caused the Apennines to grow by around 3-4cm, according to satellites and GPS stations installed in the area, which measured the movements of soil.
The stations are monitored by Italy’s National Institute of Geophysics and Volcanology (Ingv), the National Institute for Environmental Protection and Research (Ispra), and the Civil Protection Department. Some were already operating in the area, while others – including one station in Norcia, near the quake’s epicentre – were installed specifically to measure its effects.
Initial analyses show that the earthquake “was generated by a fault line of over 18km, at an incline of around 50 degrees, which ran from North-Northwest to South-Southwest,” Ingv said on the institute’s blog.
“The movement of this fault line caused a 3-4cm extension of the Apennine mountain chain between the Tyrrhenian Sea and the Adriatic Sea.”
The red and blue lines show horizontal and vertical displacements, while the squares show different GPS stations. Image: Ingv
While it has long been known that a fault line runs through the Appenines, Ingv explained that “significant” technological advantages allowing them to “pinpoint the location and extent of the movements” would help them better establish the level of hazard in the area, by improving their knowledge of tectonic movements.
The displacements measured by the GPS station in Amatrice, the worst hit town. Vertical movements are shown in red, movement to the east in green and to the north in blue. Image: Ingv
The Apennine mountain range stretches for around 1200km from the Ligurian Alps down to Calabria in the south, and the earthquake hit a remote collection of mountain villages in the regions of Umbria, Marche and Lazio.
The first earthquake struck at 3.36am in Norcia, a town south of Perugia, Umbria, at a very shallow 10km.
Shallow quakes are generally more destructive and this most recent one, measuring between 6.0 and 6.2 on the Richter scale and followed by several significant aftershocks, devastated the local area, killing 296 and leaving over 2,500 people homeless.