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La metodologia Ground Penetrating Radar nello studio di aree urbane instabili: l'esempio di Vasto.
No full textMUD VOLCANOES IN CENTRAL ITALY: SUBSOIL CHARACTERIZATION THROUGH A MULTIDISCIPLINARY APPROACH
No full textMud volcanoes are common geological phenomenons observed worldwide as in Italy. They are well described in the scientific literature for their morphological, tectonic and hydrogeological features. They represent not only a relevant geological and geomorphological interest but also not negligible elements of hazard and risk associated with the presence of soft and pliable sediments and with the possible unexpected emission of gas and mud. Therefore, the understanding of their structure and hydrogeological circuits in the subsurface is an important key to define hazard and risk conditions in the adjacent areas.
This paper deals with a multidisciplinary study including geophysical and hydrochemical surveys undertaken at the Pineto (central Italy) mud volcano site to achieve an interpretative conceptual model explaining the shallow upward migration of deep mud fluids. Shallow electrical and seismic imaging of the mud volcano was obtained using two dimensional and three dimensional (2D–3D) electrical resistivity tomography and 2D reflection seismic surveys. The hydrochemical properties of the rising fluids were assessed by means of seasonal measurements of the chemical–physical parameters, the concentrations of major ions, and some natural isotopes. This mud volcano or mud lump appears as a dome of about 15 × 10 m in size. The height of the crater is 2 m approximately, while the diameter of the crater is 2.5 m. Emission of fluids and solids (cold brine, mud, gas) occurs from this crater. Upper Pliocene–lower Pleistocene foredeep pelitic deposits (over-compacted clays with silty–sandy levels) overlain by clayey–silty deposits crop out in the area. The survey results seem to reveal that the uprising of deep fluids does not occur exactly below the mud volcano at present. Instead, a high conductivity body is present within a fractured zone in the pelitic deposits at 60 m approximately to the ENE. The probable occurrence of a high permeability layer approximately between 20 and 30 m below ground level, confined by clay deposits, gives rise to an overpressured mud fluids reservoir. Mud fluids appear to be flowing toward the surface from the reservoir up to the mud volcano crater. The interpretative conceptual model proposed by the authors is a first attempt to explain the shallow upward migration of deep mud fluids in this central Italy mud volcano. The results can be used to identify the uprising of fluids with similar chemical–physical properties even in areas where the superficial and morphological evidence of the volcanic bodies have been obliterated or covered
Shallow electrical and seismic imaging of the Pineto Mud Volcano (Central Italy)
No full textShallow underground electrical and seismic imaging was undertaken at the Pineto (Central Italy)
Mud Volcano site using 2D-3D electrical resistivity tomography (ERT) and 2D reflection seismic
surveys. This mud volcano or mud lump (known by the local population as “Cenerone Mud Volcano”)
appears as a dome of about 15x10 m in size. The height is approximately 2 m with a crater 2.5 m of
diameter where emission of fluids and solids (cold brine, mud, gas) occurs. Upper Pliocene-Lower
Pleistocene foredeep pelitic deposits (clays with silty-sandy levels) overlain by clayey-silty deposits
outcrop in the area. Below the Middle Pliocene deposits, a NNW-SSE anticline which runs
approximately 2 kilometers to the WSW of the site represents the main element of the compressional
tecnonic setting. Ditchs and streams in the area run along fault systems that are oriented NW-SE and
NE-SW. These could be related to the upward migration of deep mud fluids. 2D-ERT results were used
to determine the geometry of the high conductivity body related to the uprising of mud fluids and
detecting changes in deposits. Detailed geometry reconstruction of the shallow upward migration of mud
fluids was obtained by using 3D-ERT. A shear wave reflection seismic survey was undertaken to
determine stratigraphic limits and to assess the occurrence of fractured zones along which mud fluids
could migrate towards the surface. The survey results revealed that the uprising of deep fluids doesn’t
occur exactly below the mud volcano at present. Instead, a high conductivity body occurs at
approximately 60 m to the ENE, within a fractured zone in the undercompacted clays. The probable
occurrence of a high permeability layer approximately between 20 m and 30 m below ground level,
confined by clay layers, gives rise to an overpressured mud reservoir. This is the source of mud fluids
which flow to the surface through a mud conduit that appears nearly horizontal at depth and then
inclined towards the surface up to the mud volcano crater
The 2009 L’Aquila earthquake: a wasted opportunity to improve the seismic risk management from Italian strong earthquakes
No full textThis contribution is devoted to highlight some drawbacks in current practices for predicting seismic hazard in Italy where strong seismic events are commonly characterized by near-field conditions and high spotlight PGA measurements. The highlighted critical points are: (1) the use of Cornell’s method for defining the reference national hazard and (2) the need of multidisciplinary approaches to seismic characterization of surface geology. Some best practices from worldwide as well as past Italian experiences are reported to suggest future strategies for managing the seismic hazard at national scale. Accordingly, some results from VEL (Local Seismic Effect Evaluation) project, developed in Tuscan Region since 1998, will be briefly illustrated
Utilizzazione della metodologia GPR per la ricerca di mineralizzazioni di quarzo ametista nei basalti mesozoici della Repubblica Oriental del Uruguay
No full textExamples of site soil response induced by the 1997 Umbria-Marche seismic sequence, Italy
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Application of 1D-2D electrical resistivity surveys to the identification and investigation of shallow paleochannels in the Chamelecòn Valley (Honduras)
No full textIl lavoro confronta i risultati ottenuti dall’utilizzo di due differenti metodi di prospezione elettrica, nell’ambito di uno studio finalizzato alla ricerca e caratterizzazione di paleoalvei presenti in due siti opportunamente selezionati lungo la valle del Rio Chamelecòn (Honduras). L’applicazione di sondaggi elettrici verticali (1D) ha permesso di determinare la presenza di paleoalvei; la caratterizzazione geometrica e litologica di questi è stata invece ottenuta mediante applicazione di indagini di tomografia elettrica 2D (ERT)
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
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