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Our paper shows the preliminary results of a geophysical survey by the Ground Penetrating Radar (GPR) ultradeep "Loza 2N", in the study of buried active faults. This particular and innovative Georadar technique offers several advantages over the classic GPR techniques. Through low frequency antennas (10 MHz), it is possible to carry out deep stratigraphic studies down to about 400 m, thanks to: i) skipping of the stroboscope and cable connections between transmitter and receiver, ii) a direct digitalization of the signal, iii) the use of capacitive coupling Wu-king antennas, iv) a 21 kV (20 Mwatt) transmitter. Furthermore, the latest development of the Loza receiver performed by RTG company allows using time windows up to 512000 nsec, scanning speed up to 1000/sec and stacking up to 100 tracks/sec. These characteristics make the GPR Loza different from most of the other GPR systems that can investigate, under optimal conditions, down to a maximum depth of about 30 m. Through the GPR Loza it is possible to identify, deep stratigraphic contacts and groundwater surfaces, faults and large fracture systems at depth. The Loza interpretative sections of the underground are fully comparable with those deriving from reflection seismics, which on the other hand require costs and acquisition and processing times far larger. In this work, the performances of the instrument are illustrated for identifying the active buried fault system that borders the western edge of the plain "Il Lago" (IS) at the foot of Mount Patalecchia in the Molise Apennines (Southern Italy), an area of high seismotectonic interest. The "Il Lago" plain closes the structure of the Bojano basin towards NW and is bordered by a direct buried fault system. Historically, the area was hit by strong earthquakes: the earthquake of December 5, 1456 (I = XI MCS; Mw = 7.2) which affected central and southern Italy; the earthquake of June 5, 1688 (I = XI MCS, Mw = 7.1) with the epicentral area in the Sannio, and the earthquake of July 26, 1805 (I = X MCS, Mw = 6.7), known as the earthquake of S. Anna whose epicentral area was the Bojano plain.

The recent seismic sequence that struck central Italy, started the August 24, 2016, is characterized by five events with magnitude Mw> 5.0. The strongest events of the seismic sequence were the August 24, with Mw = 6.0 located between Accumoli and Amatrice towns and the October 30 with Mw = 6.5, located between Norcia and Visso town. These earthquakes shocked not only Central Italy, with the death of about 300 people and the almost complete destruction of historical towns (Amatrice, Arquata del Tronto, Accumoli, Pescara del Tronto, Castelluccio, Norcia, Visso), but also shook the entire Italian country, strongly proposing the issue of the vulnerability of the city historical centers. The knowledge, the conservation and preservation of the natural and urban environment represent issues to be faced urgently for preventing the devastation of our heritage, unique in the world. The historical center of Naples was affected by the 30 event October 2016 with an intensity I = V MCS. In the last millennium more than a hundred earthquakes hit Naples, with intensity I> III MCS, ten of which has exceeded the damage level, sometimes with intensity greater of VII MCS. The historical Neapolitan urban context suffered devastating effects, reaching levels of damage equal to the VIII degree MCS, as a result of the large earthquakes occurred in 1456 (I0=XI MCS), 1688 (I0=XI MCS) and 1805 (I0=X MCS). In the twentieth century the city of Napoli was shaken by the 1930, 1962 and 1980, the three strong earthquakes occurred in southern Apennines, between Irpinia and Basilicata regions. The review of earthquakes with higher energy (M> 6) shows that the metropolitan area of Naples suffered high damage levels with intensity I = VIII MCS, especially in the historical center, with a damage recurring on the same architectonic elements of the historical heritage. The recent past of the seismic history teaches us that the Apennines is highly seismic, consequently in the future we can expected seismic events of the same magnitude that could still cause damages to the city of Naples. This brief review of the strong Apennines earthquakes highlights that the city of Naples has a high seismic risk level. Therefore is crucial to implement all appropriate measures to reduce seismic risk, but also for planning measures of prevention, useful for the preservation of the rich local architectural heritage declared a World Heritage Site by UNESCO in 1995.

The history of Melito Irpino, a small village in southern Italy is particular, though not unique in its genre. The development of its urban asset was, in fact, strongly affected by natural disasters such as hydrogeological and seismic events, which determined its transfer to another location. Due to its landslides and flooding it has been included since the beginning of the twentieth century among the unstable centers to be consolidated. The landslides were caused by peculiar geological characteristics of which the substrate essentially origins from different consistency Flysch elements. From the seismic point of view, Melito Irpino is part of the first category of the new seismic classification of the Campania Region. The most devastating earthquakes that damaged Melito date back to December 1456, which hit central and southern Italy and 5th June , 1688 which had the Sannio as epicentral area, both with l0 = XI MCS and M> 7 [1456: l0= XI MCS, Mw 7.2; 1688: l0 = XI MCS, Mw 7.O.] During the twentieth century, it was involved in two other disastrous earthquakes that caused serious damage to the village in 1930 with an intensity VIII and in 1962 with I = IX MCS and VIII ESI-07 intensity. The earthquake of 21st August 1962 was fatal for the village of Melito. In December of the same year it was left with 2182 inhabitants and 800 houses, most of which were unstable, 300 were to be demolished, 50 unrepairable and 200 were still uninhabitable yet repairable. From a geological point of view the situation turned even more dramatically when the whole valley area stretching from the old Ufita River bridge and the historical center of Melito was affected by a series of large slope instability such as rock falls, complex rotational slip, de facto complicating an extremely compromised situation. This was sufficient to encourage the transfer of the entire village in an other location. After more than half a century and considering the effects of two important earthquakes in 1962 and 1980, Melito now features as rebuilt 2 km far from the original historical center. However, all measures of reconstruction have limits, positive and negative aspects. The modern urban aspect seems to be far away from the original rural connotation, which is a loss for the identity of the village. The aims of the issue are to pay attention to the reconstruction of other villages affected by similar natural disasters. How and when this should be done is a delicate and complex priority of reconstruction, which should consider the entire social and economic aspect.

This paper, by means of a multidisciplinary approach, deals with changes of the urban and territorial setting in many localities of the epicentral area of the 23 November 1980 Irpinia earthquake. The 23 November 1980 earthquake, known as the "Irpinia-Basilicata earthquake" was the strongest seismic event of the last 80 years in the Southern Apennines of Italy (Mw 6.9, I0=X MCS). It was felt nearly everywhere in Italy, from Sicily in the South, to Emilia Romagna and Liguria in the North. This earthquake was characterized by a complex main rupture, composed of three major sub-events, interpreted as a succession of normal faulting events. Many localities in the Avellino, Salerno and Potenza provinces were nearly completely destroyed (I=IX-X MSK, Postpischl et al., 1985); among them Castelnuovo di Conza, Conza della Campania, Lioni, Santomenna, San Mango sul Calore, San Michele di Serino and Sant'Angelo dei Lombardi. About 800 localities suffered serious damage (Balvano, Bisaccia, Calitri, etc); 75,000 houses collapsed totally and 275,000 were badly damaged. Casualties were 3000, and 10,000 people were wounded. A large amount of information on primary and secondary environmental effects, over all slope movements, was available on the basis of several geological surveys of the area affected by this earthquake. The amount of surface faulting was about 40 km in length and the maximum displacement about 100 cm, while the total area interested by slope movements was estimated in 7400 km2 (Porfido et al., 2002, 2007; Serva et al.2009). In this study we aim to describe trends and specific effects that have taken place in the 35 years following the 1980 earthquake: how the urban and territorial setting have changed, especially in the villages located in the epicentral area; the consequences of the environmental effects on the choices of reconstruction, both in situ, and far from the original historical centre. Therefore, some case histories as San Mango sul Calore and Calitri villages, affected by severe landslide phenomena, and in situ rebuilt, will be examined; whereas Conza della Campania, on the basis of the suffered damages, has been reconstructed far from its original position. In addition, we also illustrate the socio-economic implications that the choices of reconstruction have had, not only for the local communities, but also on the whole Italian country.

The aim of this study is a critical revision of the historical and recent seismicity of the Apulia and surrounding seismogenetic areas, for re-evaluating the macroseismic effects in MCS scale and ground effects in natural environment according to the ESI 2007 scale (Michetti et al., 2007) as a contribution to the seismic hazard of the region. The most important environmental effect due to historical earthquakes in the Apulia was the tsunami occurrence, followed by landslides, liquefaction phenomena, hydrological changes and ground cracks. The Apulia (Southern Italy) has been hit by several low energy and a few high energy earthquakes in the last centuries. In particular, the July 30, 1627 earthquake (I=X MCS, Rovida et al., 2011) and the May 5, 1646 event (I=X MCS), the strongest earthquakes of the Gargano promontory have been reviewed, together with the March 20, 1731 earthquake (I=IX MCS, Mw=6.5, Rovida et al., 2011), the most relevant of the Foggia province, and the February 20, 1743 earthquake (I=IX MCS, Mw= 7.1, Rovida et al., 2011, I ESI=X, Nappi et al, 2015), the strongest of the Salento area,. The whole Apulia region has also been struck by strong earthquakes of neighboring seismogenetic areas located in the Southern Apennines, Adriatic and Ionian Sea, Albania and Greece, well propagated throughout the Italian peninsula, and in particular in the southern regions, where the intensity degrees are higher, sometimes exceeding the limit of damage. Some well documented examples of Greek earthquakes strongly felt in the whole Apulia region were: the August 27, 1886 earthquake (Peloponnesus, Greece); the May 28, 1897 earthquake (Creta-Cypro); the June 26, 1926 earthquake (Creta and Cipro, Imax=X MCS), felt all over the Southern Italy; the August 28, 1962 earthquake (epicenter in Peloponnesus area). It is noteworthy that earthquakes located in the Southern Apennines were powerfully felt in the whole Apulia region; among the strongest historical events of the Campania-Lucania Apennines we mention the 1456 (Imax =XI MCS), 1694 (Imax =XI MCS) and 1857 (Imax=XI MCS) earthquakes. More recently, the July 23, 1930 (Imax=X MCS) and the November 23, 1980 (Imax=X MCS) Irpinia earthquakes gave rise to several ground effects, mostly hydrological variations, in the Apulian region. This study is a contribution for a better evaluation of the whole Apulia region seismic hazard that represents one of the most crowded touristic destination of the Southern Italy, all over the summer season