1,720,958 research outputs found
Detection capability of earthquakes by a hydraulic pressure device in the Gran Sasso aquifer (central Italy)
No full text
Hydroseismograms at Gran Sasso aquifer, central Italy, for earthquake hydrology studies
No full textThe use of hydroseimograms (i.e., high frequency pore pressure monitoring in wells in rock) emerges as a promising tool for a better understanding of the physics underlying earthquakes, as well as for seismic activity monitoring and/or prediction. This study investigates the earthquake detection capability of a hydraulic pressure device (HPD) installed in the Gran Sasso aquifer (GSA), Italy. The HPD, located in boreholes S13 and S14, near the INGV seismic station, GIGS, monitors hydraulic pressure changes within the aquifer. We compared data from the HPD and from GIGS to assess the HPD's ability to detect earthquakes. The analysis covered the period from May 2015 to December 2023. The HPD successfully identified 148 out of 1068 analyzed earthquakes. Compared to previous studies, our HPD displayed significantly higher sensitivity, particularly for crustal earthquakes. These HPD devices show distinctive features, such as deep location, high frequency sampling (20 Hz), and hosting wells intercepting the main fault network. The unique location of the HPD, combined with its sensitivity to seismic events, makes it a valuable tool for continuous monitoring of earthquake activity, coupled with pore pressure trends and anomalies, in the region. These results confirm the potential of the HPD system for earthquake detection within the GSA. Future studies will continue to evaluate the HPD's capabilities and its role in earthquake hazard assessment, as well as its potential use in other areas worldwide
Hydroseismograms from an underground hydrosensitive to seismicity site (Gran Sasso aquifer, central Italy)
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
Earthquake Hydrology and seismic detection capability of deep pressure devices within the Gran Sasso aquifer (central Italy)
No full textThis study investigates the potential of hydroseismograms for seismic monitoring and
understanding earthquake physics, utilizing high-frequency pore pressure measurements within
the Gran Sasso Aquifer (GSA) in central Italy. Hydroseismograms, obtained from a hydraulic
pressure device (HPD) installed in deep, horizontal wells intersecting a major fault network within
the GSA, are compared with seismic records from the nearby GIGS station to assess the HPD's
earthquake detection capabilities. This unique setting, combined with the HPD's high-frequency
(20 Hz) data acquisition system, offers a sensitive method for monitoring both seismic activity and
pore pressure anomalies. The GSA’s fractured-karst geology and its location within a high seismic
hazard zone in Italy, along with the presence of the Italian Institute of Nuclear Physics (INFN)
underground laboratory (UL), create an ideal environment for studying deep, saturated aquiferearthquake
interactions, minimizing interference from shallow hydrological processes. The UL
houses two horizontal boreholes, named S13 (190 m) and S14 (175 m), equipped with the HPD.
Approximately 250 meters from S13, the INGV seismic station GIGS, part of the GINGER
experiment, uses two broadband seismometers for continuous microseismic monitoring and
global seismicity recording. The research analyzes long-term, high-frequency pore pressure data
from the GSA, aiming to further understand the complex relationship between groundwater and
seismic activity. The primary objective of the joint analysis of well and seismic data, spanning from
May 1, 2015, to December 31, 2023 (with ongoing monitoring), is to identify and correlate
earthquake occurrence with hydraulic pressure variations detected by the HPDs in S13 and S14. A
statistical inferential approach was used to evaluate HPD sensitivity, comparing the number of
HPD-detected events with those recorded by GIGS (1068 events) across different magnitudes and
epicentral distances. Statistical analysis demonstrates the HPD’s significantly enhanced sensitivity
compared to previous studies. The HPD detected 148 of the 1068 events recorded by GIGS (a
13.9% overall success rate), with this detection probability strongly influenced by earthquake
magnitude and epicentral distance. Mainly for far events, the identified detection threshold
significantly exceeds the “hard” detection limit for typical aquifers defined by Montgomery and
Manga (2003) based on the Dobrovolski et al. (1979) criterion, a limit below which they found nodetections in a large dataset.
This finding warrants further investigation into the not yet fully understood mechanisms of
hydroseismic detection. This study, covering data from May 2015 to December 2023, reveals the
potential of HPDs installed in carbonate rock boreholes for seismic monitoring. The GSA
hydrogeological and seismotectonic conditions provide an optimal environment for HPD
deployment for both medium-to-long-term and high-frequency pore pressure monitoring. The
strategic borehole locations intersecting the main fault network offer a unique opportunity to
study the complex interplay between hydrological processes and seismic activity. Ongoing HPD
monitoring will further explore their potential as a valuable tool for future seismic studies and
contribute to the advancement of earthquake science, with implications for seismic hazard assessment and early warning systems
Variations on the Author
No full text“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
No full textWe 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
Dispelling the Myths Behind First-author Citation Counts
No full textWe 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
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