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Hydrogeochemical seismic precursors: pilot study for future hydrogeochemical networks
Get PDFThe aim of this thesis is to illustrate the importance of establishing a method of investigation of seismic precursors based on the investigation of possible relationships between groundwater and earthquakes, through hydrogeological, hydrogeochemical and seismic monitoring of the territory under consideration.
This will be done through a detailed and systematic study of hydrogeological and hydrogeochemical factors that can be potentially influenced by seismic activity, such as: piezometric levels, temperature, electrical conductivity, chemical composition of groundwater and dissolved gases in solution. The analysis of these factors will allow to verify the existence and the modalities of manifestation of a cause / effect relationship between the hydrogeological, hydrogeochemical and seismic signals.
The objective of this PhD project is therefore the study of potential geochemical precursors that will allow the short-term forecast (from days to months) of seismic phenomena of medium-high magnitude (M ≥ 5.0) in order to initiate an effective preventive action.
In particular, through this study, I want to highlight the importance of collecting data from a network of monitoring stations spread over a seismic territory and for a long time, with the construction of a national hydrogeochemical monitoring network.
The advances in identifying the earthquakes hydrogeochemical precursors depends on the systematic and patient acquisition of long-term multiparametric data set. Long records are therefore essential to identify precursor signals of earthquake responses, especially in regions with abundant seismicity. Well-developed documentation is required to assess the uniqueness and statistical significance of possible precursor signals and to identify and screen out meteorological and seasonal signals. The solid statistical significance of the results therefore depends on the length of the time series, that is the observations of more than one seismic event and the multiparametric nature of the recorded data (Ingebritsen and Manga, 2014).
The aim of this PhD project is therefore the better understanding of seismic precursors of hydrogeochemical nature and the related processes to facilitate the understanding of site-specific phenomena and their possible applicability to other sites or their general and global value
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
γ-Ray Log Tool for Detecting the Presence of Low-Permeability Lenses in High-Resolution Modelling of Contaminated Sites
Get PDFIn contaminated sites, remediation measures mostly depend on previous high-resolution site characterization (HRSC) results. In the case of industrial sites, where there is a high pollution risk for groundwater, many hydrogeological models are often achieved using stratigraphy results of geological drilling after the monitoring network design. This approach is only sometimes possible when contaminant back diffusion from small low-permeability lenses and layers occurs within a high-permeability aquifer. This framework needs a significant resolution that can be obtained by coupling preliminary stratigraphic data with specific in situ activities. Results from these additional investigations may help to locate low-permeability layers and, consequently, to identify the most vulnerable areas towards which groundwater management must be deepened. The use of gamma rays in combination with the analysis of the pluviometric and hydrometric data and together with the time series of the concentrations of a given analyte can provide indispensable support for site characterization, the development of numerical groundwater contamination models and remediation procedures when back diffusion occurs. In this study, within an industrial site in the province of Benevento (Italy), based on stratigraphy, a 3D hydrogeological model has been set up and coupled with results of natural gamma radioactivity logs to detect the release of Chromium VI from low-permeability lenses. © 2023 by the authors
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Hydrogeochemical anomalies before the 2016 Mw 6.0 and 6.5 earthquakes in Italy: new data and possible relationship with deep CO2 influx
No full textHydrological and hydrogeochemical changes caused by pre- and co-seismic processes have been reported
for thousands of years. Transient hydrogeochemical anomalies are increasingly becoming commonly recorded
before M ≥ 5.0 earthquakes at distances between 20 and more than 200 km from the earthquake epicenters. The
2016 Amatrice and Norcia earthquakes as well as the related sequence were anticipated by hydrogeochemical
anomalies, in particular, since April 2016 an increase of As and V contents was recorded in groundwater from
springs monitored in the Sulmona area about 70 km to the southeast of the epicentral area, and in a spring located
within the epicentral area. On November 2016, these elements recovered their original very low concentrations.
We considered these geochemical anomalies as reliable seismic precursors of the case-study for a dilatational
tectonic setting. To validate these parameters as reliable seismic precursors and, consequently, to constitute
an effective predictive tool, it is necessary to move from observed site-specific anomalies in groundwater to
the comprehension of the geological and geochemical processes driving these anomalies. A pre-seismic and
co-seismic elemental contribution from the bituminous-asphaltic residues and/or hydrothermal fluids could
be hypothesized. However, neither additional metal (e.g. Ni, Mn) nor TDS or water isotope anomalies, which
should be consequential of hydrocarbon decomposition and fluid mixing, respectively, have been detected.
Consequently, a different possible source of the anomalies the steady characteristics of groundwater flow and
the simultaneous increase of selected metal ions has been evaluated. Chemical and isotope models reveal that
the abnormal content of As and V and the concomitant lowering of the boron isotopic ratios up to + 2‰ may be
due to mineral desorption (e.g. from iron oxides and/or clays). Based on these data, the geochemical processes
that led to the cited metal element increase in groundwater would be related in a new perspective on possible
deep CO2 input. Furthermore, new data on the isotope ratios of the dissolved boron show potential application
of the δ11B parameter as potential precursory signal of earthquakes, at least in the study area
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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