5 research outputs found
Passive seismology and deep structure in central Italy
n the last decade temporary teleseismic transects have become a powerful tool for investigating the crustal and upper mantle structure. In order to gain a clearer picture of the lithosphere-asthenosphere structure in peninsular Italy, between 1994 and 1996, we have deployed three teleseismic transects in northern, central, and southern Apennines, in the framework of the project GeoModAp (European Community contract EV5V-CT94â0464). Some hundreds of teleseisms were recorded at each deployment which lasted between 3 and 4 months. Although many analyses are still in progress, the availability of this high quality data allowed us to refine tomographic images of the lithosphere-asthenosphere structure with an improved resolution in the northern and central Apennines, and to study the deformation of the upper mantle looking at seismic anisotropy through shear-wave splitting analysis. Also, a study of the depth and geometry of the Moho through the receiver function technique is in progress. Tomographic results from the northernmost 1994 and the central 1995 teleseismic experiments confirm that a high-velocity anomaly (HVA) does exist in the upper 200â250 km and is confined to the northern Apenninic arc. This HVA, already interpreted as a fragment of subducted lithosphere is better defined by the new temporary data, compared to previous works, based only on data from permanent stations. No clear high-velocity anomalies are detected in the upper 250 km below the central Apennines, suggesting either a slab window due to a detachment below southern peninsular Italy, or a thinner, perhaps continental slab of Adriatic lithosphere not detectable by standard tomography. We found clear evidence of seismic anisotropy in the uppermost mantle, related to the main tectonic processes which affected the studied regions, either NEâSW compressional deformation of the lithosphere beneath the mountain belt, or arc-parallel asthenospheric flow (both giving NWâSE fast polarization direction), and successive extensional deformation ( EâW trending) in the back-arc basin of northern Tyrrhenian and Tuscany. Preliminary results of receiver function studies in the northern Apennines show that the Moho depth is well defined in the Tyrrhenian and Adriatic regions while its geometry underneath the mountain belt is not yet well constrained, due to the observed high complexity.Published479-4934T. SismicitĂ dell'ItaliaJCR Journa
Rapid response seismic networks in Europe: lessons learnt from the L'Aquila earthquake emergency
<p>The largest dataset ever recorded during a normal fault seismic sequence was acquired during the 2009 seismic emergency triggered by the damaging earthquake in L'Aquila (Italy). This was possible through the coordination of different rapid-response seismic networks in Italy, France and Germany. A seismic network of more than 60 stations recorded up to 70,000 earthquakes. Here, we describe the different open-data archives where it is possible to find this unique set of data for studies related to hazard, seismotectonics and earthquake physics. Moreover, we briefly describe some immediate and direct applications of emergency seismic networks. At the same time, we note the absence of communication platforms between the different European networks. Rapid-response networks need to agree on common strategies for network operations. Hopefully, over the next few years, the European Rapid-Response Seismic Network will became a reality.</p>
Rapid response to the earthquake emergency of May 2012 in the Po Plain, northern Italy
Rapid-response seismic networks are an important element
in the response to seismic crises. They temporarily improve
the detection performance of permanent monitoring
systems during seismic sequences. The improvement in earthquake
detection and location capabilities can be important for
decision makers to assess the current situation, and can provide
invaluable data for scientific studies related to hazard, tectonics
and earthquake physics. Aftershocks and the clustering
of the locations of seismic events help to characterize the dimensions
of the causative fault. Knowing the number, size and
timing of the aftershocks or the clustering seismic events can
help in the foreseeing of the characteristics of future seismic
sequences in the same tectonic environment.
Instrumental rapid response requires a high degree of
preparedness. A mission in response to a magnitude (ML) 6
event with a rupture length of a few tens of kilometers
might involve the deployment within hours to days of 30-50
seismic stations in the middle of a disaster area of some hundreds
of square kilometers, and the installation of an operational
center to help in the logistics and communications.
When an earthquake strikes in a populated area, which is almost
always the case in Italy, driving the relevant seismic response
is more difficult. Temporary station sites are chosen
such as to optimize the network geometry for earthquake
locations and source study purposes. Stations have to be installed
in quiet, but easily reachable, sites, and for real-time
data transmission, the sites might need to have optical intervisibility.
The operational center can remain in a town if
there is one within the damaged area, and it should coordinate
the actions of the field teams and provide information
to colleagues, the Civil Protection Authorities and the general
public. The emergency system should operate as long
as the seismic rate remains high; the duration of any mission
might also depend on the seismic history of the area involved.
This study describes the seismic response following
the May 20, 2012, ML 5.9 earthquake in northern Italy, which
included rapid deployment of seismological stations in the
field for real-time seismic monitoring purposes, the coordination
of further instrumental set-ups according to the spatial
evolution of the seismic sequence, and data archiving
The management of acute venous thromboembolism in clinical practice - study rationale and protocol of the European PREFER in VTE Registry
Background: Venous thromboembolism (VTE) is a major health problem, with over one million events every year in Europe. However, there is a paucity of data on the current management in real life, including factors influencing treatment pathways, patient satisfaction, quality of life (QoL), and utilization of health care resources and the corresponding costs. The PREFER in VTE registry has been designed to address this and to understand medical care and needs as well as potential gaps for improvement. Methods/design: The PREFER in VTE registry was a prospective, observational, multicenter study conducted in seven European countries including Austria, France Germany, Italy, Spain, Switzerland, and the UK to assess the characteristics and the management of patients with VTE, the use of health care resources, and to provide data to estimate the costs for 12 months treatment following a first-time and/or recurrent VTE diagnosed in hospitals or specialized or primary care centers. In addition, existing anticoagulant treatment patterns, patient pathways, clinical outcomes, treatment satisfaction, and health related QoL were documented. The centers were chosen to reflect the care environment in which patients with VTE are managed in each of the participating countries. Patients were eligible to be enrolled into the registry if they were at least 18 years old, had a symptomatic, objectively confirmed first time or recurrent acute VTE defined as either distal or proximal deep vein thrombosis, pulmonary embolism or both. After the baseline visit at the time of the acute VTE event, further follow-up documentations occurred at 1, 3, 6 and 12 months. Follow-up data was collected by either routinely scheduled visits or by telephone calls. Results: Overall, 381 centers participated, which enrolled 3,545 patients during an observational period of 1 year. Conclusion: The PREFER in VTE registry will provide valuable insights into the characteristics of patients with VTE and their acute and mid-term management, as well as into drug utilization and the use of health care resources in acute first-time and/or recurrent VTE across Europe in clinical practice. Trial registration: Registered in DRKS register, ID number: DRKS0000479