Search results for "GEOF"

Assessment of a geological model by surface wave analyses

2016

A set of horizontal to vertical spectral ratio (HVSR) and multichannel analysis of surface waves (MASW) measurements, carried out in the Altavilla Milicia (Sicily) area, is analyzed to test a geological model of the area. Statistical techniques have been used in different stages of the data analysis, to optimize the reliability of the information extracted from geophysical measurements. In particular, cluster analysis algorithms have been implemented to select the time windows of the microseismic signal to be used for calculating the spectral ratio H/V and to identify sets of spectral ratio peaks likely caused by the same underground structures. Using results of reflection seismic lines, ty…

A multidisciplinary non-invasive approach in geoarchaeology conducted on the archaeological area of Selinunte

2019

Southwestern Sicily is an area of infrequent seismic activity. Only an earthquake occurred in the Belice valley on 13 January 1968 is reported in the historic earthquake catalogues (see e.g. [1]) as severe event, that is characterized by moderate-high energy (M=6.5) and significant epicentral and local macroseismic intensities (Io=X and I=VII-VIII of the MCS scale). Nevertheless, some studies (e.g. [2]) suggest that probably at least two earthquakes struck this area, between the fourth century B.C. and the early Middle Ages, with energy able to damage and produce collapse in some temples of Selinunte. In this framework, we propose the use of non-invasive approaches in geoarchaeology for det…

Near surface seismostratigraphic modelling of the Bandita plain in Palermo town (Italy) from integra-ted analysis of HVSR and stratigraphic data

2016

The Horizontal to Vertical Spectral Ratio (HVSR) noise method (Nakamura, 1989) is nowadays widely used to estimate the resonance frequencies of geological structures (Bonnefoy-Claudet, 2006). However, often HVSR is also used to obtain information on the depth of the seismic bedrock and on thickness and seismic velocity of the process overburden deposits, using inversion techniques of the H/V curve (Fäh et al., 2003). This nevertheless produce results with large uncertainty intervals of parameters, and then must be necessarily constrained by detailed stratigraphic information. An application of HVSR inversion is presented in order to verify the effectiveness of this technique for purposes of…

Seismic microzonation by means of cluster analysis

2019

The identification of areas with uniform behaviour in seismic perspective is a very complex task that involves the simultaneous assessment of many parameters. In this paper we propose an automatic procedure for the seismic microzonation based on cluster analysis and performed by means of an agglomerative hierarchical algorithm. It exploits a proximity matrix specifically defined on the parameters space and the average linkage criteria. The procedure has been used to carry out the expedite seismic microzonation of some high seismic hazard areas, only using the data inferred by the extensive application of the HVSR technique. The results of the clustering procedures have been assessed from a …

Improvement of HVSR technique by cluster analysis

2014

Werewolves and warning signs: Cultural responses to tropical cyclones in Mauritius

2022

The role that culture plays in the way different groups experience, respond to, and recover from disasters has been widely discussed. Yet, while there is a considerable (and growing) literature of case study evidence for the need to account for culture in disasters, comparatively few studies take a long-term perspective on cultural interactions with disasters, resulting in a lack of exploration into the diachronic nature of these cultural responses, both past and present. The literature that does exist tends also to focus either on western cultures or on groups that pursue highly traditional livelihoods. Communities that call on elements of both local or vernacular knowledge and scientific …

Geophysical contribution to the reconstruction of the hydrological model of "Barcellona-Milazzo plain" groundwater body, northen Sicily

2019

The “Barcellona-Milazzo plain” groundwater body in the northen Sicily, was analysed in detail, through numerous geophysical measurements that were integrated with stratigraphic data in order to reconstruct the hydrological model. The “Barcellona-Milazzo plain” (BMP) groundwater body has been identified within the coastal sector between the village of Oliveri, to the west, and Capo Rasocolmo, to the east. It also includes several rivers that rise further south in correspondence with the Peloritani ridge and flow into the wide Barcellona-Milazzo alluvial plain. On the basis of several geophysical and geological data analysis and interpretation have been used to reconstruct the composition and…

Seismic Network Evaluation through Simulation: An Application to the Italian National Seismic Network

2011

Abstract A properly organized seismic network is a valuable tool for monitoring seismic zones and assessing seismic hazards. In this paper we propose a new method (seismic network evaluation through simulation, SNES) to evaluate the performance of hypocenter location of a seismic network. The SNES method gives, as a function of magnitude, hypocentral depth, and confidence level, the spatial distribution of the number of active stations in the location procedure and their relative azimuthal gaps, along with confidence intervals in hypocentral parameters. The application of the SNES method also permits evaluation of the magnitude of completeness ( M C ), the background noise levels at the sta…

Long-Term Consequences of Water Pumping on the Ecosystem Functioning of Lake Sekšu, Latvia

2020

Cultural eutrophication, the process by which pollution due to human activity speeds up natural eutrophication, is a widespread and consequential issue. Here, we present the 85-year history of a small, initially Lobelia&ndash

CEFLES2: The remote sensing component to quantify photosynthetic efficiency from the leaf to the region by measuring sun-induced fluorescence in the …

2009

The CEFLES2 campaign during the Carbo Europe Regional Experiment Strategy was designed to provide simultaneous airborne measurements of solar induced fluorescence and CO<sub>2</sub> fluxes. It was combined with extensive ground-based quantification of leaf- and canopy-level processes in support of ESA's Candidate Earth Explorer Mission of the "Fluorescence Explorer" (FLEX). The aim of this campaign was to test if fluorescence signal detected from an airborne platform can be used to improve estimates of plant mediated exchange on the mesoscale. Canopy fluorescence was quantified from four airborne platforms using a combination of novel sensors: (i) the prototype ai…