The educational broadband seismic network
at Naples (Southern Italy)
Antonella Bobbio1,2 and
Aldo Zollo 2
Since 1995 the Scientific Museum "Città della Scienza" and our group at the
University of Naples started a cooperation aimed at developing modern educational
tools in Earth Sciences. With this purpose, a number of educational
activities and exhibits have been implemented and are presently operated in the museum
and the Department of Physical Sciences. These are mainly addressing to the public
visiting the museum, high school teachers and students.
During 1996-1998 two broadband seismic stations were installed in Naples, at the
Museum of Science and at the Department of Physical Sciences in the University campus.
The museum seismograph is deployed in an exposition room dedicated to the volcanoes
and to the themes of seismic monitoring in volcanic and tectonic areas. The seismometer
in the Museum responds to different purposes: it records the earthquakes on the whole
Planet and functions as an interactive hands-on exhibit through which the visitors
(most of all are students) observe live the seismograms produced by their own movement.
Following the successfull experience in USA of the Princeton Earth
Physics Project
(PEPP)
(lead by Prof. G.Nolet and Prof. R. Phinney) a similar initiative was launched in
Europe since 1997, called the Educational Seismology project
(EduSeis, Virieux et al., 1999; Virieux, 2000),
by the Nice (France) and Naples University groups with the creation of an
educational broad-band seismic network to be installed in schools and museums.
The fundamental aim of the
EduSeis European Network is to confront
school students with the current practice of scientific data acquisition and management.
Recent networking developments make data and tools, previously only accessible
in research laboratories, now also available in the classroom.
The basic idea behind the project is that seismological observations can be a vehicle
to train the active use of modern technologies, learn about the dynamics and evolution
of the Earth and create public awareness about the seismic activity and hazard.
These objectives are accomplished by operating and maintaining a high-tech,
but low-cost seismic station (sensor, data acquisition board and
data acquisition software and processing) to be installed in schools, science
centres/museums and other places open to schools and the general public.
All components of the seismic station are especially designed for educational
purposes and can be operated independently by the students and teachersi themselves.
Presently, in southern Italy four additional EduSeis stations are operated in three
high schools ("Copernico" ,downtown Naples; "Ettore Majorana", Isernia, 100 km north of
Naples and IPSIA, Pozzuoli, 15 km west of Naples) and in a 100m deep borehole drilled on
the slope of Mt. Vesuvius volcano, 25 km east of the town of Naples (Figure 1).
In particular the borehole station is part of a cooperative scientific and educational
project between Osservatorio Vesuviano,
University of L'Aquila and the University of Naples.
Figure 1. Map of the educational broadband seismic network at Naples and Isernia.
The data acquisition system relies on a concept of automatized procedures
for station control, mantainance and the availability of user-transparent software protocols
for data retrieval and processing. For the southern Italy Eduseis network the data retrieval
and management tasks are accomplished by a server (located at the Department of
Physical Sciences) connected to the Internet and to the telephone line, running
under the LINUX operating system.
The server controls the station and performs the following tasks:
- Daily authomatic data retrieval
- Detection of data transmission failures and automatic procedure restart
- Preliminary data processing and archiving using the WEB facilities and data access.
Software for remote control of the stations and data retrieval have been developed
by the group in Nice, with the support of Agecodagis srl, who produced the A/D card.
After retrieving the earthquake location and origin time through the Internet from
National and global earthquake agencies, the relevant seismic records are recovered
via modem through a daily call to every station of the network.
The retrieved seismic waveforms are preliminary processed
(filtering, windowing, glitch removal, ..) and transformed to the standard
SAC format
suitable for educational software applications.
A seismic data archive is created and updated on the server and made accessible to
schools and the broader public through the WEB using a rather simple data-base architecture
(see EduSeis).
Software for data formatting and archiving have been developed by the group in Naples.
The seismic waveforms can be either downloaded for local applications or remotely
displayed by the Internet browser through a tcl/tk graphic tool developed by
André Herrero in Naples.
This allows for a seismogram quick view, zooming, arrival time picking
and main phase identification based on the IASPEI91 travel time tables (Figure 2).
Figure 2. Example of seismogram quick-view and phase detection through the web using
the tcl/tk applet.
A nearly real-time display of the ground motion recording at the station NAPI,
located in the
caves of the Department of Physical Sciences, is also available on the WEB through a
Java-based tool developed by Luca D'Auria in Naples (Figure 3). Based on an amplitude
threshold criterion, an automatic alert procedure is active, which sends an e-mail to
the web manager in case a relevant regional or large global earthquake occurs.
Figure 3. Near real time recording at station NAPI of the event occurred on November
16, 2000, at New Ireland (M=8.0)
The Eduseis project is also an ideal framework for testing and developing
seismic station components for educational and research purposes. For instance, the Eduseis
stations in Italy and France operate presently a 24-bit A/D card specially designed for the
school project by Agecodagis srl in France (J.Virieux, 2000).
Since about two years we started to investigate and test tri-axial seismic sensors
available on the market, which may be suitable for educational purposes (low-cost,
broad-band frequency response and wide dynamic range).
The seismic stations operating in southern Italy are equipped with different sensor types.
This enable us to make a quantitative comparison of instrument responses and characteristics.
Figure 4 displays the horizontal components of ground velocity for an earthquake that
occurred on the Sakhalin Islands (Russia) August 4, 2000
as recorded at stations ISMI and NAPI.
Both stations are equipped with a broadband sensor (PMD Scientific, 20s-20Hz).
VESI is equiped with a short-period sensor (Mark Product, 1-25 Hz) and
BENI with an accelerometer (EPISENSOR-Kinemetrics, 10s-100Hz).
The traces have been 0.05-0.5Hz band-pass filtered.
In France the EduSeis stations are equipped with PMD and Guralp products.
Figure 4. Band-pass filtered recordings at stations of the EduSeis network of the EW
component of the ground motion velocity for the Ms=7.1 Sakhalin Island earthquake
occurred on August 4, 2000.
The EduSeis project has recently received financial support from the Italian Ministry
of Civil Protection (through the National Group for Earthquake Defense) to use the
educational seismograph as a tool for training and awareness on the seismic risk.
This project is coordinated by the Scientific Museum "Città della Scienza di Napoli"
with the participation of the Institute GeoAzur at the University of Nice, the Department of
Physical Sciences at the University of Naples and the high school
"Liceo Scientifico Copernico" in Naples.
The educational activity is organized at different levels for teachers, students and
the broader public.
A small group of high school teachers participate in practises at university
laboratories during which they use the seismic station, analyze and interpret seismic data
under the scientific assistance of researchers.
For these practises we design and prepare didactic modules dedicated to the seismological
practice and to seismic risk evaluation. These modules are used and verified in schools and
musea by students and visitors, who provide feedback for adaption and inclusion in the
italian scholar curricula.
We thank L. D'Auria and A. Herrero for the continuous software and
technical support. E. Balzano, L. Cantore, F. Di Martino, C. Paolantonio and M. Simini work
at the Eduseis data management and preparation of school activities. We thank J. Virieux,
J.L. Berenguer and the Nice group for their participation and support to the EduSeis
project. The Eduseis project is supported in Italy by ING-GNDT (2000).
- Virieux, J., 1999,
EDUSEIS, An EDUcational SEISmological European Network, Orfeus Electronic
Newsletter, 1, 13
- Virieux, J., 2000, Eduvational Seismological Project: EDUSEIS, Seismological Research Letters, 71, 530-535
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