The Influence of Fractures on Vulnerability to Pollution of a Carbonate Aquifer: Monte Conero (Italy)

The carbonate outcrops of the anticline of Monte Conero (Italy) were studied in order to characterize the geometry of the fractures and to establish their influence on the petrophysical properties (hydraulic conductivity) and on the vulnerability to pollution. The outcrops form an analog for a fractured aquifer and belong to the Maiolica Fm. and the Scaglia Rossa Fm. The geometrical properties of fractures such as orientation, length, spacing and aperture were collected and statistically analyzed. Five types of mechanical fractures were observed: veins, joints, stylolites, breccias and faults. The types of fractures are arranged in different sets and geometric assemblages which form fracture networks. In addition, the fractures were analyzed at the microscale using thin sections. The fracture age-relationships resulted similar to those observed at the outcrop scale, indicating that at least three geological episodes have occurred in Monte Conero. A conceptual model for fault development was based on the observations of veins and stylolites. The fracture sets were modelled by the code FracSim3D to generate fracture network models. The permeability of a breccia zone was estimated at microscale by and point counting and binary image methods, whereas at the outcrop scale with Oda’s method. Microstructure analysis revealed that only faults and breccias are potential pathways for fluid flow since all veins observed are filled with calcite. According this, three scenarios were designed to asses the vulnerability to pollution of the analogue aquifer: the first scenario considers the Monte Conero without fractures, second scenario with all observed systematic fractures and the third scenario with open veins, joints and faults/breccias. The fractures influence the carbonate aquifer by increasing its porosity and hydraulic conductivity. The vulnerability to pollution depends also on the presence of karst zones, detric zones and the material of the vadose zone.

Characterization of fold-related fractures in the carbonate rocks of the Cingoli anticline, northern Apennines, Italy

Thrust fault-related folds in carbonate rocks are characterized by deformation accommodated by different structures, such as joints, faults, pressure solution seams, and deformation bands. Defining the development of fracture systems related to the folding process is significant both for theoretical and practical purposes. Fracture systems are useful constrains in order to understand the kinematical evolution of the fold. Furthermore, understanding the relationships between folding and fracturing provides a noteworthy contribution for reconstructing the geodynamic and the structural evolution of the studied area. Moreover, as fold-related fractures influence fluid flow through rocks, fracture systems are relevant for energy production (geothermal studies, methane and CO2 , storage and hydrocarbon exploration), environmental and social issues (pollutant distribution, aquifer characterization). The PhD project shows results of a study carried out in a multilayer carbonate anticline characterized by different mechanical properties. The aim of this study is to understand the factors which influence the fracture formation and to define their temporal sequence during the folding process. The studied are is located in the Cingoli anticline (Northern Apennines), which is characterized by a pelagic multilayer characterized by sequences with different mechanical stratigraphies. A multi-scale analysis has been made in several outcrops located in different structural positions. This project shows that the conceptual sketches proposed in literature and the strain distribution models outline well the geometrical orientation of most of the set of fractures observed in the Cingoli anticline. On the other hand, the present work suggests the relevance of the mechanical stratigraphy in particular controlling the type of fractures formed (e.g. pressure solution seams, joints or shear fractures) and their subsequent evolution. Through a multi-scale analysis, and on the basis of the temporal relationship between fracture sets and their orientation respect layering, I also suggest a conceptual model for fracture systems formation.

Diversity of the proximal femur in humans: morphological variations of the head-neck junction

The proximal femur is a high-diversity region of the human skeleton, especially at the anterior junction between head and neck, where various bony morphologies have been recognized since mid nineteenth century. Classical literature on this topic is chaotic and contradictory, making almost impossible the comparison of data from different researches. Starting from an extensive bibliographic review, the first standardized method to score these traits has been created. This method allows representing both the anatomical diversity of the region already described in literature and a part of variability not considered before, giving few and univocal definitions and allowing to collect comparable data. The method has been applied to three identified and five archaeological European skeletal collections, with the aim of investigating the distribution of these features by sex, age and side, in different places and time periods. It has also been applied to 3D digital reconstructions of femurs from CT scan files of coxo-femoral joints from fresh cadavers. In addition to the osseous traits described in the standardized method, the presence and frequency of some features known as herniation pits have been scored both on bones and on CT scans. The various osseous traits of the proximal femur are present at similar frequencies in skeletal samples from different countries and different historical periods, even if with clear local differentiation. Some of the features examined show significant trends related to their distribution by gender and age. Some hypotheses are proposed about the etiology of these morphologies and their possible implication with the acquisition of bipedalism in Humans. It is therefore highlighted the possible relation of some of these traits with the development of disorders of the hip joint. Moreover, it is not recommended the use of any of these features as a specific activity-related marker.

The "Orthoplastic" combined surgical approach to open tibia fractures: a multicentric prospective outcome study

Introduction: Open fractures of the leg represent a severe trauma. The combined approach, shared between plastic and orthopaedic surgeons, is considered to be important, although this multidisciplinary treatment is not routinely performed. Aim of this study was to verify whether the orthoplastic treatment is of any advantage over the traditional simply orthopedic treatment, through a multicentric inclusion of these unfrequent injuries into a prospective study. Material and methods: The following trauma centres were involved: Rizzoli Orthopaedic Institute/University of Bologna (leading centre) and Maggiore Hospital (Bologna, Italy), Frenchay Hospital (Bristol, United Kingdom), Jinnah Hospital (Lahore, Pakistan). All patients consecutively hospitalized in the mentioned centres between January 2012 and December 2013 due to tibial open fractures were included in the study and prospectively followed up to December 2014. Demographics and other clinical features were recorded, including the type of treatment (orthopaedic or orthoplastic). The considered outcome measures included duration of hospitalization, time for bone union and soft tissue closure, Enneking score at 3, 6 and 12 months, the incidence of osteomyelitis and other complications. Results: A total of 164 patients were included in the study. Out of them 68% were treated with an orthoplastic approach, whereas 32% received a purely orthopedic treatment. All considered outcome measures showed to be improved by the orthoplastic approach, compared to the orthopaedic one: time for soft tissue closure (2 versus 25 weeks), duration of hospital stay (22 versus 55 days), time for bone union (6 versus 8.5 months) , number of additional operations (0.6 versus 1.2) and functional recovery of the limb at 12 months (27 versus 19, Enneking’s score). All results were statistically significant. Conclusion: The combined orthoplastic approach to the treatment of open tibia fractures, in particular for high grade injuries (Gustilo 3B), is proven to improve the outcome of these severe injuries.

The use of expandable megaprostheses for reconstruction of the distal femur in pediatric patients after bone tumor resection

Expandable prostheses are becoming increasingly popular in the reconstruction of children with bone sarcomas of the lower limb. Since the introduction of effective chemotherapy in the treatment of these pathologies, in the 70s, there has been need for new limb salvage techniques. In children, limb salvage of the lower limbs is particularly challenging, not in the last place, because of the loss of growth potential. Therefore, expandable prostheses have been developed. However, the first experiences with these implants were not very successful. High complication rates and unpredictable outcomes raised major concerns on this innovative type of reconstruction. The rarity of the indication is one of the main reasons why there has been a relatively slow learning curve and implant development regarding this type of prosthesis. This PhD thesis, gives an overview of the introduction, the development, the current standards, and the future perspectives of expandable prostheses for the reconstruction of the distal femur in children.

Flow of Complex Fluids in Geological Fractures

In this study, the lubrication theory is used to model flow in geological fractures and analyse the compound effect of medium heterogeneity and complex fluid rheology. Such studies are warranted as the Newtonian rheology is adopted in most numerical models because of its ease of use, despite non-Newtonian fluids being ubiquitous in subsurface applications. Past studies on Newtonian and non-Newtonian flow in single rock fractures are summarized in Chapter 1. Chapter 2 presents analytical and semi-analytical conceptual models for flow of a shear-thinning fluid in rock fractures having a simplified geometry, providing a first insight on their permeability. in Chapter 3, a lubrication-based 2-D numerical model is first implemented to solve flow of an Ellis fluid in rough fractures; the finite-volumes model developed is more computationally effective than conducting full 3-D simulations, and introduces an acceptable approximation as long as the flow is laminar and the fracture walls relatively smooth. The compound effect of shear-thinning fluid nature and fracture heterogeneity promotes flow localization, which in turn affects the performance of industrial activities and remediation techniques. In Chapter 4, a Monte Carlo framework is adopted to produce multiple realizations of synthetic fractures, and analyze their ensemble statistics pertaining flow for a variety of real non-Newtonian fluids; the Newtonian case is used as a benchmark. In Chapter 5 and Chapter 6, a conceptual model of the hydro-mechanical aspects of backflow occurring in the last phase of hydraulic fracturing is proposed and experimentally validated, quantifying the effects of the relaxation induced by the flow.