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Abstract: In this paper we give an overview of the recent geophysical, geochemical and volcanological studies concerning the island of Ischia within the geological and tectonic framework of Southern Italy. Ischia is an active volcanic field that had a complex volcanic history resulting from dominant explosive and minor effusive activity, several caldera collapses, and renewed volcanism from vents located inside the collapsed area. The island is morphologically dominated by Mt. Epomeo, the result of a prominent resurgence phenomenon taking place since ca. 33ka BP, and responsible for ca. 900m of total uplift, one of the largest known compared to the relatively small size of the caldera. The uplift was accompanied by activation of faults, seismic activity and renewal of volcanism, and may be considered a main factor for inducing slope instability. For Ischia, volcanological, petrological and geophysical studies are, at present, limited compared to the other active volcanoes of the Neapolitan Area. Furthermore, the island is characterized by high volcanic, seismic and hydrogeological risks. Thus, this review is aimed at highlighting aspects of the knowledge on Ischia that need more investigations, in order to better assess some characteristics of its structural setting. Features such as the precise location of the caldera boundaries and the depth of the magma chamber representing the drive for the resurgence still need to be well defined. A critical analysis of all lines of evidence relevant to the current theories about the island resurgence (resurgent block vs. resurgent dome) has been carried out. Our analysis reveals that the resurgent block model, differently from the resurgent dome model, is consistent with the most significant features, such as tilting of the resurgent block, faults type, dip and distribution at the edges of the block, and occurrence of most of the past 10ka eruption vents on the eastern sector of the island. However, as both model require an input of fresh magma into the shallow plumbing system, it is not clear at present how much magma was necessary to achieve the measured uplift, and whether the drive was provided by magma or magmatic volatiles. [Copyright &y& Elsevier]

Abstract: We start from the general inverse problem for potential fields and discuss the validity and suitability of using not only horizontal variations of them, but also their vertical ones. Hence multilevel data sets are considered, being they obtained either from measured data at different levels or by measuring the field just at the lower level and then generating by upward continuation the data at the remaining upper levels. In the latter case the upward continued data must be considered as the true ones plus some errors due to experimental errors and to the fact that they are generated from a discrete data set known on a finite survey area. Several forms of a priori information, such as that assuming the source can be represented by a fault or a sheet sandwich model, may allow the information contained in multilevel data to be effectively used for the interpretation of gravity and magnetic data. Recently established techniques of analysis, such as the continuous wavelet transform, are applied successfully to potential fields using implicitly the information contained in multilevel data. Assuming a block model for the source domain, the upward continuation formula may help to improve the solution of either 1D, 2D or 3D inverse problems enlarging the system with the equations related to the vertical variations of the fields, thereby reducing the algebraic ambiguity. Meaningful and computationally suitable quantities, such as weighted averages of potential fields, are also closely related to the use of multilevel data, providing useful insights for the determination of the depth distribution of the sources. [Copyright &y& Elsevier]

The main objective of the present study is to evaluate seismic attenuation relationships for the Campanian area (southern Italy) using the felt intensity report data obtained from comprehensive historical databases (DOM 4.1). We focused our attention on the Campania region because it is characterized by a high seismic hazard and risk, particularly in the Naples area and its suburbs. In order to derive an attenuation relationship for the area, we fitted the observed data by using several functions. We found that a linear plus logarithmic model gives the best fits for the data in the Campanian region. Most of the attenuation relationships proposed up to now for the Italian Peninsula have an isotropic behavior and do not always properly describe the macroseismic attenuation. Therefore, in order to check the possible dependence of the attenuation on the azimuth of the seismic rays, we divided our data set in octants and performed for each of them the same analysis we carried out for the whole data set. The obtained results differ from octant to octant and the differences, besides being associated with the source effects, could be interpreted as probably due to the existence of lateral variations in the lithological and physical features of the crust at different depths, which could affect the patterns of attenuation. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we recall a method for medium scale (level-2) zoning of seismic-induced landslide susceptibility and present its application to the Sannio–Irpinia area, Southern Italy. Previous small scale studies of the entire Campania Region identified this area as one of the most susceptible to earthquake-induced landslides in the region. The area’s intense seismic and landslide activity and the characteristics of the deposits involved in landslides make this analysis an interesting case study for land planning, management and protection of an area characterized by high seismic and hydrogeological hazard. The result of the zoning shows good agreement between the distribution of the historical earthquake-triggered landslides and the areas defined by the method as the most susceptible ones. They also highlight the method’s effectiveness in the presence of complex clayey deposits. [Copyright &y& Elsevier]

Abstract: In this paper we present a study of the structural setting of the volcanic island of Ischia by the analysis and interpretation of high-resolution aeromagnetic and self-potential data recently acquired over the island. The magnetic data allowed us to locate the main anomaly sources and lineaments of the island and its offshore surroundings, while the self-potential (SP) data provided information on both the structural pattern of the resurgent caldera and the high-temperature fluid circulation. An inversion of the acquired magnetic and SP data, and a joint modelling of the magnetic data and of a previous gravity data set along a SW–NE profile allowed us to build a model of the island. The model is characterized by the presence of an igneous–very likely trachytic–structure, whose top is located at 1200–1750 m b.s.l. Such a body, possibly formed by several neighbouring intrusions, has a density contrast with the pyroclastic cover of about 0.4 gr/cm3 and its central-western part, below Mt. Epomeo, seems to be demagnetized. The demagnetization should be connected to the high geothermal gradient measured in this portion of the island and may be due to hydro-chemical alteration processes and/or to the possible presence of partially melted spots within the intrusion. Our outcome is consistent with the results of previous geophysical, geo-volcanological and geothermal studies. [Copyright &y& Elsevier]

Abstract: A gravity investigation was carried out in the Somma–Vesuvius complex area (Campania, Italy) based on a dataset recently enlarged with new measurements. These cover the volcanic top and fill some other important spatial gaps in previous surveys. Besides the new gravity map of the Vesuvius, we also present the results of a 3D inverse modelling, carried out by using constraints from deep well exploration and seismic reflection surveys. The resulting density model provides a complete reconstruction of the top of the carbonate basement. This is relevant mostly on the western side of the survey area, where no significant information was previously available. Other new information regards the Somma–Vesuvius structure. It consists of an annular volume of rocks around the volcanic vent and that extends down to the carbonate basement. It results to be denser with respect to the surrounding sedimentary cover of the Campanian Plain and to the material located just along the central axis of the volcanic structure. The coherence between these features and other geophysical evidences from previous studies, will be discussed together with the other results of this research. [Copyright &y& Elsevier]

Several bidimensional seismic tomography surveys were carried out in urban areas of the Campi Flegrei and Somma-Vesuvius volcanic districts, Naples, Italy, with the aim of investigating the shallow subsurface and of detecting small-scale variation and heterogeneities within pyroclastic deposits. The method employed in this study is turning ray tomography (TRT). With accurate field acquisition and travel time picking and correct choice of inversion parameters, it was possible to obtain detailed P-wave tomographic models in areas characterized by thick beds of pyroclastic deposits. We were able to identify zones with heterogeneous P-wave velocities caused by the presence of buried paleochannels, or by differential welding and zeolitization in the subsurface of the investigated areas. TRT appears to be a suitable method to investigate deposits for engineering applications, at sites where the bedrock is too deep to be reached by foundations and the overburden is characterized by much heterogeneity. [Copyright &y& Elsevier]

Background: Dental practitioners desire non-pharmacological methods to alleviate anxiety, fear, and pain in children receiving dental care; high-quality evidence, however, is required to evaluate methods' efficacy., Aim: This study aimed to develop and validate an observation-based coding approach (paediatric dental pain, anxiety, and fear coding approach [PAFCA]) to evaluate non-pharmacological behavior management techniques for anxiety, fear, and pain., Design: Objective (video-based) and subjective (self-reported) anxiety, fear, and pain data were collected from a pilot clinical trial evaluating animal-assisted therapy (AAT) in paediatric dentistry, in which 37 children aged 7-14 were assigned to AAT or control before dental treatment (restorations or extractions). A coding approach utilizing a codebook, a gold standard calibration video, and a user training guide was developed. Trained examiners coded the gold standard video for inter-rater agreement, and masked, calibrated examiners analyzed videos using the Noldus Observer XT software., Results: A novel, software-based coding approach was developed, with moderately high inter-rater agreement. Using PAFCA, we found children reporting higher levels of pain, fear, and anxiety exhibited treatment-interfering behaviors, including crying/moaning, attempts to dislodge instruments, and more upper and lower body movements., Conclusion: PAFCA shows promise as a reliable tool for assessing anxiety, pain, and fear in behavioral research for paediatric dentistry., (© 2024 The Author(s). International Journal of Paediatric Dentistry published by BSPD, IAPD and John Wiley & Sons Ltd.)