Riviste Online SApienza - R.O.SA - 2 (Sapienza University of Rome)
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The flea collection of the Museum of Zoology, Sapienza University of Rome (Insecta: Siphonaptera)
No full textThe Museum of Zoology of Sapienza University of Rome (MZUR) houses a collection of fleas encompassing about 1300 specimens, representing 132 species and 10 families. Most of these specimens were collected in Italy and neighboring countries. The flea collection has been digitalized and is now accessible through a freely available dataset, which includes information from the labels of each preserved specimen. Additionally, an overview of the collection, a checklist of the preserved taxa and photos of selected specimens are provided
Engineering geology on the thread of memory
No full textThe invitation to deliver a talk on his 80th birthday gave Prof. Rinaldo Genevois the opportunity to look back on his life in the light of the evolution of what Applied Geology meant and what it means today. The thread of memory runs over a period of more than 40 years through four different universities where he studied, researched and taught this discipline, progressively changing its content and participating in the continuous expansion of its fields of application. After a brief historical excursus, his journey begins in the late 1960s and ends with his retirement. At the same time, Applied Geology was transformed from a strictly naturalistic science, as defined by Ardito Desio, to a complex and structured discipline as defined by the IAEG in 1970, which can best be denoted by Engineering Geology. The story looks above all at that people who has directly participated in this long journey largely first as students and later as passionate researchers
Assessing local seismic response in major-hazard industrial plants: implications for natech events
No full textSeismic events can trigger a NaTech disaster, leading to the release of hazardous materials, fires, and explosions. These can occur within industrial complexes and along distribution networks as a result of natural disasters. Industrial plants, composed of structural and non-structural components, may be damaged when subjected to earthquakes of a given magnitude. Some examples of these disasters occurred in Kobe (1995), Kocaeli (1999), and Tohoku (2011). This study aims to assess the local seismic hazard by the implementation of different analytical approaches in a Major-Hazard Industrial Plant (MHI P) triggering a NaTech event. For the Bussi MHI P area, a geodatabase has been designed where geometric and geotechnical parameters have been associated with each geotechnical unit. The local seismic hazard has been simulated using 1D and 2D codes, considering two seismic hazard scenarios limit state SLV - SLC according to the National Building Code (NTC2018). In this study, the amplification factor AF has been calculated within the natural vibration range of an H2O2 storage tank located in the Bussi MHI P facility. This type of structure was chosen as it represents an element able to generate a relevant accident and consequently, a potential NaTech event
Engineering-geological insights into the gypsum-bearing deposits of Punta delle Pietre nere (Puglia Region, Italy)
No full textIn a very limited area near Punta delle Pietre Nere (Puglia region, Italy), chalky deposits crop out along with black limestones interspersed with bituminous marls and igneous rocks. From 1927 to 1930 these gypsums were affected by some works that modified the path of the Acquarotta Canal to connect the close lagoon (Lesina Lake) to the sea and facilitate its flow conditions. Over time, the strip of land close to the Acquarotta Canal was affected by sinkhole phenomena related to the dissolution of the chalk. These phenomena also occurred in the nearby town of Lesina Marina. Since 1990, numerous investigations have been carried out in the area, including geological, hydrogeological and geomechanical surveys, geo-electrical and seismic surveys, and remote sensing analyses. In this study, we present the results of recent site-specific investigations, which enabled to better understand the buried limits of the chalky deposits, their depth, the geological characteristics of the covering soils and the groundwater flow conditions. In summary, the distribution of gypsum-bearing deposits in the subsoil of the area is now better defined than in the past, when the uncertainty of the data represented a factor strongly limiting the local possibilities of settlements’ development
Assessment of the mechanism of excessive deformations encountered in a large-span tunnel excavation using analytical and 3D numerical analyses
No full textT8 tunnel (L=3826 m) is located in Dogancay Section in Ankara-İstanbul High Speed Railway Project. The tunnel was designed and excavated with New Austrian Tunnelling Method (NATM). The tunnel route was composed of granite, mudstone, and shale units. A part of the tunnel route between km:142+280 - 142+360 contains landslides. While determining the tunnel route, it is desirable to avoid landslides as much as possible. However, due to the geometrical restrictions of a high-speed railway, it is necessary to pass through the landslide or parts close to the landslide. As part of the Ankara-Istanbul High-Speed Railway Project, the T8 tunnel, the construction of which was completed in Adapazarı, Doğançay section, was excavated under landslides. As a result of the geotechnical investigations including borehole and in-situ tests, the tunnel roof altitude was designed to be 10 m below the failure surface of the landslide. During the excavation in this region in the tunnel, excessive deformations occurred in places that exceeded the maximum deformation tolerance of 15 cm. However, tunnel stability was achieved with improvements and additional support. The purposes of the study are to explain the excessive deformations that occurred during the excavation stage and to understand the effect of the landslide on these deformations using analytical and 3D numerical analyses. Within the purpose of the study, the relationship between a tunnel and a landslide is investigated, and support systems for these types of problems are described. The results showed that the main source of the excessive deformations and failures in the tunnel is due to the high horizontal pressures caused by the landslide material on the surface. Consequently, the results of the study may provide a scientific basis for the optimum support design of tunnel construction under landslides
Rock engineering and its obsession with rock bridges: why everything we call real cannot be regarded as real
No full textRock bridges are critical in determining the stability of rock slopes and underground excavations. However, measuring them is impossible since their definition extends beyond a mere geometrical problem. Rock bridges are understood primarily in the context of rock mass strength, representing known unknowns akin to the principle of complementarity in physics. The current understanding suggests that while we can measure rock bridges post-failure, their pre-failure definition and measurement elude us. Historically, researchers have focused on the geometric perspective of rock bridges, with limited attempts to investigate actual field evidence. This has led to a disconnect between the theoretical problem and practical measurement. Since Terzaghi first highlighted this issue in 1962, more progress has yet to be made in addressing the fundamental limitations of our understanding of rock bridges. This paper argues for a paradigm shift towards analyzing rock bridges through the lens of rock mass damage and recognizing that rock bridge strength is directionally dependent
Engineering-geological modelling as a tool for archaeological site preservation strategies
No full textTraditionally, cultural heritage (CH) site conservation strategies have mostly focused on the employment of procedures to protect archaeological exhibits from weathering processes. However, CH-sites are often located in areas affected by geological hazards, which can threaten the conservation of the site itself. For these cases, engineering-geological modelling is an essential tool to design conservation strategies for geohazards management in the framework of CH-site preservation. The research here proposed is focused on the Punta Eolo promontory at Ventotene island (Italy) where the remnant of the roman “Villa Giulia” emperor palace is hosted. Detailed engineering-geological surveying has been carried out at Punta Eolo. In particular, engineering-geological investigations have been coupled with remote investigation of the area of interest. Thanks to the engineering-geological surveys, a detailed engineering-geological map was drafted, also highlighting the geomechanical setting of the Parata Grande Tuff formation (hereinafter, PGT). The presence of a superficial deposit, mainly composed of archaeological material overlaying a tuffaceous unit, was evidenced. To bound this layer’s thickness more effectively, 52 single-station seismic noise measurements were carried out. Seismic ambient noise measurements show significant horizontal-to-vertical spectral ratio (HVSR) resonance peaks at 3 Hz, a variable secondary peak ranging from 9 to 19 14 Hz, respectively related with the contact between the PGT and the underlying lavas and the superficial deposits and PGT units. The measurements conducted at the edge of the promontory show evidence of polarization of the particle motion potentially related to the vibrational behavior of the unstable rock blocks that bound all the site. A 3D model of the cliff, reconstructed by drone photogrammetry technique, allowed to perform the rock mass joints surveying along the not-accessible cliff faces, as well as to visualize the superficial deposits thickness all around the perimeter of the promontory. Additionally, a 3D geological model was made using the RockWorks 16 program to facilitate a more direct visualization of site-specific features. The engineering-geological model here presented enables the development of an efficient conservation strategy for the Villa Giulia archeological site, as a critical tool for mitigating geological risks. Furthermore, future archaeological excavation will be driven by the reconstructed geological model of Punta Eolo
Sinkhole occurrence and evolution, and seawater intrusion in a low-coastal setting of Apulia
No full textIn the last decades, the scientific community has paid an increasing attention on coastal karst areas, since these are highly urbanized and populated, and attract high number of tourists. This transition zone where anthropogenic, terrestrial, and marine processes simultaneously act, is intrinsically fragile, and its vulnerability to geological hazards is enhanced by the mixing between fresh and salt waters, causing a stronger dissolution on carbonate rocks. In this paper, a case study located along the coastal karst of Apulia, between the provinces of Bari and Brindisi, in one of the most touristic areas of the Region is described. In detail, this manuscript deals with description sinkholes evolution at the coastal zone and seawater intrusion in coastal aquifer. The case study highlights the influence of sinkholes in the modification of coastal geomorphology, potentially leading to natural hazards in terms for communities, urbanized land, and infrastructures. The geological setting presents the Cretaceous limestone bedrock overlain by more recent Cenozoic calcarenites and Quaternary marine terrace deposits. The topography is controlled by structural discontinuities, mainly oriented in SW-NE direction. This area is locally defined “Costa Merlata”, which means “Merlon coast”, as it resembles the merlons of a medieval castle. This is due to a strong control exerted by sinkholes in the genesis of bays and inlets. In fact, in this stretch of the Adriatic coastline, it is possible to observe important freshwater outflows, including the main spa of central Apulia (Torre Canne spa), and several evidence of sinkholes, including recent collapse at a few meters from the coastline. The morphologic evolution is characterized by different phases: individual openings of sinkholes, which evolve to small inlets showing the larger sinkhole inland, accompanied by minor openings toward the sea; the last phase is characterized by well-developed bays, deriving from coalescence of sinkholes, overall entering inland for some tens of meters, by means of progressive failures, also favored by sea-storms. In addition to the sinkhole hazards, the area is affected by inland seawater intrusion. In fact, the hydrogeological setting of the coastal stretch, extending for about 25 km, shows evidence of groundwater salinization, with salinity values ranging from 0,5 g/l to more than 5 g/l. The springs with high discharge rate are in the sand dunes zone (Fiume Grande, Fiume Piccolo, and Fiume Morello) and discharge hundreds of liters of freshwater per second, while several diffuse springs, often with unknown discharge, are submerged. In such complex zone, caves adopted as groundwater monitoring spots, especially near the sea, where fresh water and sea water meet. The latter is also carried out by monitoring of stygofauna, i.e. animal species living exclusively within groundwater. Stygofauna can be considered environmental indicator and natural tracer, since it is highly sensitive to environmental variation; therefore, studying groundwater ecosystems will allow to characterize the groundwater quality and the main freshwater pathways
Multi-temporal evolution analysis of Maronti Cliff (Ischia Island, Italy) derived from multi-perspective photographic datasets
No full textCoastal cliff erosion is a significant hazard for the safety of people, buildings, utilities and infrastructure, given the sudden and episodic nature of the retreat process in time and space. Thus, understanding past retreat trends and a regular diagnosis of the cliff face condition is fundamental for risk management. In this study we show preliminary results of a project aimed at the definition of the coastal erosion (in terms of temporal and spatial scales) of a small portion of cliff located along the Maronti beach in Ischia, Italy. Drone-based and terrestrial acquisition approaches offered the opportunity to exploit photogrammetric techniques to estimate the spatial and temporal rate of change of the investigated portion of cliff. In this study, cliff face topographical evolution is evaluated out by comparing the results obtained from three photographic datasets (variable approach either boat and UAV-based) obtained in 2011, 2021 and 2023. Spatial distribution of two main instability events dated back to 2020 and 2022 were well represented in the maps of change generated with the M3C2 algorithm. The comparison of point clouds for the period 2011-2021 and 2021-2023 produced max retreat rate of the cliff face of approximately 12 and 25 m, respectively. Results highlighted the need for robust co-registration methods to accurately estimate erosion rates. Critical issues are discussed to highlight potentials and limitations encountered with the abovementioned multi-temporal cliff evolution assessment techniques
The geology of the San Leo Cliff (Northern Apennines, Italy)
No full textThe main objective of this work is to deduce the geologic setting of the San Leo cliff from the natural sections exposed in its own rock walls. The line-drawings of the rock walls, coupled with a detailed geologic map and framed in a tectonostratigraphic scheme, allow us to reconstruct a 3D geological model of the San Leo cliff . The interpretation of the collected data also allows us to establish the relationships between lithostratigraphy, tectonics and geomorphology that control the evolution of this spectacular and delicate landscape emergency of Val Marecchia. The 2014 landslide (Borgatti et alii, 2015) has been only the latest event in the evolution of the San Leo cliff , where fractures and faults of Late Pliocene to Present age have predisposed rock masses to fall, so that the current slope morphology is the result of a very long series of rockfalls (Benedetti et alii, 2011)