1,721,030 research outputs found
Seismotectonic analysis of the complex fault system named "Garfagnana-Nord" (Northern Tuscany)
No full textCaratterizzazione di faglie tramite indagini sismologiche: il caso della linea Saorge-Taggia, Liguria Occidentale
No full textQuali parametri relativi al moto ondoso possono essere ricavati attraverso l’analisi del microsisma? Una applicazione nel Mar Ligure
No full textGeodynamic evolution of the Ligurian Sea area (Northern Italy): hypothesis of modelization from geological and geophysical data
No full text
Reliability of the automatic procedures for locating earthquakes in South Western Alps and Northern Apennines (Italy)
No full textAutomatic P- and S-wave local earthquake tomography: testing performance of the automatic phase-picker engine "RSNI-Picker"
No full textIn this work, we test a fully automatic procedure to obtain local earthquake tomography (LET), starting from seismic waveforms and applying the capability of the automatic phase picker and locator engine “RSNI-Picker” (Spallarossa et al., 2014), which is based on a multistep iterative procedure working on P and S arrival times. This code is currently operating as part of the Earthquake Monitoring System at the University of Genoa (RSNI designates the regional seismic network of northwestern Italy). In particular, we compare P- and S-wave tomographic results obtained using this fully automatic procedure for picking and locations with those based on data from accurate manual picking and revised locations. We use a dataset of 409 earthquakes that occurred in the Trentino region (Northeastern Italy) in the 1994–2007 period. The highly variable waveform qualities (e.g., signal-tonoise ratio), mainly due to recording stations equipped with different types of sensors and digitizers (including both one-component narrowband stations and three-component broadband seismic stations), ensure a severe test for the automatic procedure. The comparison of the two 3D velocity propagation models for the Trentino region (i.e., LET images) from the automatic and manual procedures, shows maximum differences of 0.54 and 0:34 km=s for P and S waves, respectively (if we consider 90% of all the computed absolute velocities, as a reference percentage). The automatic LET shows velocity anomaly distributions and reliability patterns (e.g., resolution diagonal element [RDE] values) similar to those obtained using the manual procedure; 90% of RDE differences are lower than 0.15. The results obtained by testing the RSNI-Picker engine suggest it can be used to automatically process large amounts of seismic recordings in order to identify P and S wavepicks for reliable LET analysis
Applicability of an empirical law to predict significant sea-wave heights from microseisms along the Western Ligurian Coast (Italy)
No full textThe use of microseisms with appropriate predictive laws is a reliable method for estimating such seawave parameters as period and significant height. Through the use of opportune predictive laws calibrated with measurements obtained from wave buoys, it is possible to determine the significant height of
the wave as a function of the spectral energy-content of the microseism. In this paper we will present a
procedure that utilises microseisms recorded by a micro network of five seismic stations to predict the
significant height of waves, and its uncertainty, along the western Ligurian coast (Italy). The calibration
and validation of the procedure was performed using wave measurements obtained from a wave buoy off
Capo Mele (Imperia, Italy) over a two and a half year period. The differences between the significant
heights measured by the wave buoy and the empirical predictions were less than 10 cm (corresponding
to 10% of the mean measured value) for 47% of the data and less than 20 cm (corresponding to 20% of the
mean measured value) for 72%
Seismotectonic analysis of a complex fault system in Italy: the "Garfagnana-North" (Northern Tuscany) line
No full text- …
