The southern Apennines reveals to the scholars of the National Institute of Geophysics and Volcanology the presence of magma deep in the Sannio-Matese area. The discovery emerges from a study, conducted by a team of Ingv researchers and the Department of Physics and Geology of the University of Perugia (DFG-UNIPG) entitled 'Seismic signature of active intrusion in mountain chains', and published in Science Advances. The research impacts on the knowledge of the structure, composition and seismicity of mountain ranges, on the upwelling mechanisms of magmas and gases and on how to monitor them.The data collected show that the gases released by this magma intrusion consist mainly of carbon dioxide, arrived on the surface as a free or dissolved gas in the aquifers of this area of the Apennines. According to experts, this magma could cause earthquakes, even of high intensity. "Mountain ranges are generally characterized by earthquakes attributable to the activation of faults that move in response to tectonic forces - explains Francesca Di Luccio, INGV geophysicist and coordinator, with Guido Ventura, of the research group - however, by studying an anomalous seismic sequence, which took place in December 2013-2014 in the Sannio-Matese area with a maximum magnitude of 5, we discovered that these earthquakes were triggered by an upwelling of magma in the crust between the 15 and 25 km deep. An anomaly linked not only to the depth of the earthquakes in this sequence (between 10 and 25 km), compared to the more superficial one in the area (10-15 km), but also to the waveforms of the most important events, similar to those of earthquakes in volcanic areas ”.” This result - adds Guido Ventura, Ingv volcanologist - opens up new avenues for identifying the areas where magma rises in mountain ranges and highlights how such intrusions can generate earthquakes of significant magnitude. The study of the composition of the aquifers also makes it possible to highlight the thermal anomaly "." It is to be excluded that the magma that has crossed the crust in the Matese area can reach the surface forming a volcano - adds Giovanni Chiodini, geochemist of Ingv - However , if the current process of accumulation of magma in the crust were to continue, it cannot be excluded that, on the scale of geological times (ie thousands of years), a volcanic structure could form ". During the study, seismic and geochemical data were collected and developed models on the rising of fluids. The research began with the analysis of the seismicity of the Sannio-Matese sequence, and then ended with the modeling of the magmatic intrusion conditions.
