1,720,994 research outputs found
Geomorphological mapping for liquefaction likelihood: the Piniada Valley case study (central Greece)
No full textAssessment of liquefaction susceptibility of sediments in alluvial plains is considered one of the first step for infrastructure planning, hazard mitigation, and land use management in seismically active regions. Subtle geomorphological features resulting from depositional processes could greatly contribute to estimating the liquefaction likelihood since they also dictate the type and distribution of sediments. Our case study is from the Piniada Valley (Greece), where widespread liquefaction phenomena were triggered by the 2021 Mw 6.3, Damasi earthquake. As we compiled a detailed geological map for the purposes of this investigation and correlated it to the spatial distribution of the earthquake-induced liquefaction phenomena, we observed that most of liquefaction surface evidence are related to point bars and abandoned river channels formed the last century. In particular, the areal liquefaction density was estimated at 60.7 and 67.1 manifestations per km(2), for the point bars and abandoned channels, respectively. Following this outcome, we propose a refinement of the existing liquefaction susceptibility classifications by including point bar bodies as a distinct category, characterized by a very high susceptibility to liquefaction. In addition, we discuss the correlation between the observed liquefaction manifestations and the shallow lithofacies, sand or mud prone areas, within point bars. The outcome arisen by this research is that most of liquefaction phenomena (> 70%) occurred on the area covered by coarser materials deposited on the upstream part of high sinuosity meanders
Surface effects of the strong June 8, 2008, NW Peloponnese earthquake
No full textThe main goal of this paper is the description of the quantitative and qualitative characteristics of the secondary effects triggered by the June 8th, 2008 earthquake. The earthquake-induced ground deformations were spread into a large area up to 25Km of epicentral distance. Surface ruptures were mapped at the areas close to the villages of Mihoi, Psari and Nisi where the maximum horizontal and vertical displacement was equal to 15cm and 20cm, respectively. Furthermore, typical liquefaction-induced surface disruptions were reported at the coastal area of the villages Kato Achaia, Alikes and at the shore of the lake Pinios close to the villages Roupakia and Kalivia. Moreover, small scale liquefaction phenomena were observed at the banks of the river Pinios and at the area of Nisi. In addition, landslides and rockfalls were mapped into a large area and caused damages to the road network of Peloponnesus, particularly to the roads connecting the villages of Santomeri, Portes at the mountain Skollis
Using geological quantitative data for the assessment of the seismic hazard in Greece and the surrounding region.
No full textLiquefaction phenomena along the paleo-Reno River caused by the May 20, 2012, Emilia (northern Italy) earthquake
Full text linkOn the May 20, 2012 (04:03:52 local time; 02:03:52 UTC), a moderate earthquake (Ml 5.9) [Scognamiglio et al. 2012, this volume] with a focal mechanism showing E-W-trending, S-dipping, reverse-faulting occurred in the eastern sector of the alluvial plain of the Po River, close to the border between the Regions of Emilia-Romagna and Lombardia (northern Italy). The tectonic structure is completely blind, but it was well known from a dense grid of seismic profiles for hydrocarbon explorations [e.g., Pieri and Groppi 1981, Toscani et al. 2009]. The earthquake triggered extensive liquefaction-induced ground effects at the surface, and caused severe structural damage to nonreinforced masonry and precast industrial buildings within the broader epicentral area. The hypocenter was at 44.89 ˚N, 11.23 ˚E, at a depth of 6.3 km [Scognamiglio et al. 2012], while the maximum acceleration was recorded in Mirandola, with peak ground acceleration 310 cm/s2 and 264 cm/s2 along the vertical and horizontal components, respectively [Bozzoni et al. 2012, this volume]. In this report, we focus on a zone including the Sant'A-gostino, San Carlo and Mirabello villages (west Ferrara Province), which were built along an abandoned reach of the Reno River and where liquefaction phenomena were particularly diffuse, with very intense local effects. […]</p
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
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe 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
The use of geological data to improve SHA estimates in Greece
No full textThe broader Aegean region is well known for the frequent and intense seismic activity which has caused great damages and human losses. In order to improve the seismic hazard assessment (SHA) in Greece and surroundings, several national and international projects were launched during the past years dealing with either the cause (seismogenic sources) and/or the result (ground effects). In this paper, we present the background and the state-of-the-art of two databases which contribute (each with its own way) to the SHA of Greece: GreDaSS (Greek Database of Seismogenic Sources) and DaLO (Database of Liquefaction Occurrences). Both databases are essentially built on geological information and investigation approaches and techniques. They confirm the important contribution of Earthquake Geology to an explicit improvement of our seismotectonic knowledge and to SHA analyses when this information is included in the estimates
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