36 research outputs found
Gypsum physical mechanical characterization and influence on geological risks in quarry environment
Preliminary Mineralogical Characterization of Branching Selenite Gypsum: New Insights for the Paleoenvironmental Reconstruction and Mechanical Characterization
The present study proposes a characterization of textural and mineralogical features of branching selenite gypsum lithofacies from the Monferrato area (NW Italy). This facies is considered to have appeared during the sequence of the primary lower gypsum of the Messinian Salinity Crisis starting from the sixth stratigraphical cycle, providing a useful tool for stratigraphic correlation throughout the Mediterranean. It is often associated with thick and continuous beds that are exploited by open-pit and underground quarries. We provide the results of a characterization of the non-gypsum minerals that represent approximately 10% in weight of the rock. Mineralogical data were collected with energy-dispersive X-ray spectroscopy (EDS) and X-ray powder diffraction (XRPD) techniques. In addition, a detailed characterization of clay families was performed through dedicated XRPD analyses. Results highlight the presence of detrital minerals (quartz, feldspars and clay minerals), calcite, dolomite and epsomite. Clay analysis registered the existence of five different families (illite, chlorite, smectite and two mixed layers). These mineralogical data suggest that the origin of this lithofacies is connected to both depositional processes and in situ precipitation processes under different conditions of saturation of the brine (respectively undersaturated and supersaturated in sulfates). The mineralogical and textural heterogeneity also represents an important element in controlling the mechanical response of the material and the consequent stability of quarry sites
Crack coalescence and strain accommodation in gypsum rock
Gypsum is a soft rock with low strength and high propensity to plastic deformation. Its mechanical properties are relevant in a wide range of technical application (e.g. tunnel excavation, stability assessment of underground quarries, oil and gas accumulation). The micro-mechanisms involved in the deformation of gypsum rock have for long time interested the scientific world and are still not completely understood. The peculiar crystallographic structure of this bi-hydrate salt, with water molecules layered in the salt structure, favours the development of plastic structures in the rock.
The present work proposes an experimental investigation of strain accommodation mechanisms in gypsum rock, reporting data referred to uniaxial and triaxial stress conditions. The rock strain was studied with a multiscale approach, with the comparison of results from DIC and microstructural analyses
Geophysical surveys for non‐invasive characterization of sinkhole phenomena: a case study of Murisengo
The present research investigates the morphology and genetical mechanism of a sinkhole which occurred in 2019 in Murisengo (NW Italy). This landform is representative of several subsidence phenomena that often concern the Monferrato area (NW Italy). In concomitance with the appearance of the sinkhole at the surface, a cone of detrital material was found in the drifts of a nearby underground quarry. A geological survey was performed in the underground quarry in order to understand the interaction between the geological and geostructural features of the rock body and the generation of the sinkhole. Moreover, the underground sinkhole morphology was investigated through electrical resistivity tomography (ERT) surveys performed at the surface. The ERT outputs were combined to obtain a 3D image of the phenomenon and the 3D reconstruction was then compared with the geomorphological and structural setting of the area. Results suggest that a viscoplastic flow of clay-rich sediments within a conduit in the gypsum bedrock (suffusion process) generated the sinkhole
A new computational approach to analyze human protein complexes and predict novel protein interactions
We propose a new approach to identify interacting proteins based on gene expression data. By using hypergeometric distribution and extensive Monte-Carlo simulations, we demonstrate that looking at synchronous expression peaks in a single time interval is a high sensitivity approach to detect co-regulation among interacting proteins. Combining gene expression and Gene Ontology similarity analyses enabled the extraction of novel interactions from microarray datasets. Applying this approach to p21-activated kinase 1, we validated α-tubulin and early endosome antigen 1 as its novel interactors
Groundwater Resources Assessment for Sustainable Development in South Sudan
The economic activities of South Sudan (East-Central Africa) are predominantly agricultural. However, food insecurity due to low agricultural production, connected with weather conditions and lack of water infrastructure and knowledge, is a huge problem. This study reports the results of a qualitative and quantitative investigation of underground and surface water in the area of Gumbo (east of Juba town) that aims to assure sustainable water management, reducing diseases and mortality and guaranteeing access to irrigation and drinking water. The results of the study demonstrate the peculiarity of surface and groundwater and the critical aspects to take into account for the water use, particularly due to the exceeding of limits suggested by the WHO and national regulation. The outcomes provide a contribution to the scientific overview on lithostratigraphic, hydrochemical and hydrogeological setting of a less-studied area, characterized by sociopolitical instability and water scarcity. This represents a first step for the improvement of water knowledge and management, for sustainable economic development and for social progress in this African region
Instrumental Monitoring of a Slow-Moving Landslide in Piedmont (Northwest Italy) for the Definition of Rainfall Thresholds
The prediction and prevention of landslide hazard is a challenging topic involving the assessment and quantitative evaluation of several elements: geological and geomorphological setting, rainfalls, and ground motion. This paper presents the multi-approach investigation of the Nevissano landslide (Asti Province, Piedmont, NW Italy). It shows a continuous and slow movement, alongside few paroxysmal events, the last recorded in 2016. The geological and geomorphological models were defined through a field survey. An inventory of the landslide’s movements and rainfall records in the period 2000–2016 was performed, respectively, through archive investigations and the application of “Moving Sum of Daily Rainfall” method, allowing for the definition of rain thresholds for the landslide activation (105 mm and 193 mm, respectively, in 3 and 30 days prior to the event). The displacements over the last 8 years (2016–2023) were monitored through an innovative in-continuum monitoring inclinometric system and Earth Observation (EO) data (i.e., relying on Interferometric Synthetic Aperture Radar, or InSAR data): it gave the opportunity to validate the rainfall thresholds previously defined. This study aims to provide information to public authorities for the appropriate management of the site. Moreover, the proposed workflow could be adopted as a guideline for investigating similar situations
Underlying Event measurements in pp collisions at and 7 TeV with the ALICE experiment at the LHC
An Interdisciplinary Approach to the Sustainable Management of Territorial Resources in Hodh el Chargui, Mauritania
The present study proposes an analytical investigation of the natural resources and social framework of the Hodh el Chargui region (Mauritania), aiming to offer a useful instrument for planning and management to the local authorities. The situation of the region was evaluated by means of a participatory survey carried out among the local inhabitants. The obtained results include a collection of data about population, territorial organization, access to basic education and health services, infrastructure, main economic activities, and natural resources (in terms of water, both surface and groundwater, duration and intensity of rainfalls, soil types, and vegetal resources). The survey outcomes were completed with an integrated approach based on Earth Observation (EO) data supports, such as digital elevation models (DEMs) and Landsat8 imagery. The interdependence among the different data was evaluated and discussed, with regard to the influence of the availability of natural resources on the development of agricultural activities and on the general social welfare. The results are organized in the form of digital maps and a user-friendly webmap platform to facilitate access for all the technical and nontechnical actors involved in the project