GNGTS 2014 - Atti del 33° Convegno Nazionale

GNGTS 2014 S essione 2.1 21 RUMBLES AND MISTPOEFFERS IN VAL PELLICE (WESTERN PIEDMONT) WITH AND WITHOUT EARTHQUAKES: A COMPARISON BETWEEN RADON 222 AND INFRASOUNDS MONITORING AND UNUSUAL ANIMAL BEHAVIORS G. de Liso 1,2,3 , A. Viotto 1 1 Seismic Precursors Study Center (SPSC), Torre Pellice (TO), Italy 2 Istituto di Alta formazione artistica e musicale G.F. Ghedini, Cuneo, Italy 3 Voce Pinerolese, Pinerolo (TO), Italy Historical accounts and local people witnesses: a perceptive description of rumbles. The area of Val Pellice, located in western Piedmont, has a moderate seismicity, the recent classification of the seismic risk is 3S, but sometimes it is the theatre of earthquakes with magnitudes greater than 4 and 5 Richter, like the famous seismic event of April 2, 1808, with a magnitude recently estimated in 5.7 Richter. Regarding this latter earthquake, we have in Pinerolo an interesting relation of physicist G. Eandi and of captain L. Garola: they reported several observations during the long period of the following seismic storm, recording monitoring of chemical and physical parameters, unusual animal behaviors, anomalous atmospheric phenomena and seismic rumbles. Recently, the first author has added to monitoring of a few physical parameters also a research about local people witnesses of pre-seismic and seismic observations. It is very interesting to note that people living near the top of Vandalino Mountain or near Castelluzzo Peak, are better qualified to observe nature than people living in the centre of villages in Val Pellice: so during a seismic period, more observations by farmers are possible about anomalous animal behaviors and rumble or mistpoeffers. A statistic research on this topic is going on, but it is necessary to consider a more consistence of anthropic influences in centre of villages or little tows and different geologic morphology of areas of Castelluzzo-Bonnet, Vandalino’s top, outer hamlets of Angrogna, Villar Pellice, Bobbio Pellice and Rorà. The no-profit association Seismic Precursors Study Center (SPSC), which collects these data, is located in Torre Pellice (44°49’235” N, 7°123’04” E, western Piedmont, NW Italy) at 699 m above sea level on Vandalino Mountain, not too far an abandoned iron mine, near a particular “geological sanctuary” (Compagnoni and Sandrone, 1981) of Castelluzzo. The area of Castelluzzo and Bonnet is rich in augen-gneiss, of eruptive origin, in biotite, ophiolite, zeolite, pechblenda and in “Luserna Stone” (gneiss). Around Castelluzzo Peak it is possible to observe a slight geothermal activity, with warm emission of sulphureous gases from rock cracks. It is also interesting to note in the local toponymy a few names that have evident connection with the presence of creeks with moderately warm water (Rive chaud, La Chauda…). This is also present in areas of Barge (Cuneo), near Bracco Mountain and near Rocca of Cavour. Both mountains have characteristics similar to those of Vandalino Mountain. In Val Pellice it is possible to hear frequently rumbles, and it is necessary to do an accurate description of them, on the basis of perceptive acquisition of their origin, direction and temporal term. Often these rumbles follow the rapid rise of grey-ochre clouds from ground depressions at the top of Vandalino, or near Castelluzzo, or near the Bric Bucie (Bobbio Pellice). The rumbles can be perceived as underground or air rumbles: a)- underground rumbles can be perceived as long underground thunders, as underground rolls of timbals or of kettle drums (not of drums without resonance case), as an underground landslide of big rolling stones, as underground “mistpoeffers” similar to far gun shots, but acoustically stifled, “brontides”, similar to the closing of a big underground door; b)- rumbles in air can sometimes perceived as single blows in air, without echo, or wind blows, with a temporal long term, or as far gun shots in air, with a long period of detonation. Taking into consideration the historical accounts of Eandi, it is important to underline that the observations of Eandi and Garola are similar to those reported by the first Author, in the same region, in Val Germanasca and Val Chisone. ��������� ����� �� �� ����������� �������� �� Moreover, there is an interesting citation in poetic verses of lyric aria “La calunnia è un venticello”, written by the composer Gioacchino