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In 1999, FOTON 2000
SELF S.R.L in alliance with National Institute of Research and
Development for Earth Physics
have
founded the Seismological Monitoring and Alert System for Bucharest
with integral private capital.
From March 2002 on the basis of O.G. 26/2000, S.M.A.S. is part of The
Romanian Institute for Applied Seismology.
The Seismic Alert System for Bucharest is calculated to prevent people
and industrial units
with
25 - 30 seconds before a major earthquake wave arrives from Vranceain
Bucharest.
The Real Time Seismic Warning System principle is to detect the primary
seismic wave "p" in the epicenter
and to
give the Radio-Paging Alert before the secondary seismic wave
"s" (which is a destructive wave) arrives in Bucharest.
The primary "p" wave or compression wave has the average travel
velocity 7.8 Km/sec
for our
epicenter area. The secondary seismic wave "s" (or transversal wave)
has the average travel velocity 4.6 Km/sec.
The seismic alert time about 25 - 30 seconds.
The Seismic Stations are located in epicenter area and transmit
continuously (in real time) radio signals
with
information about seismic activity in epicenter. At
S.M.A.S. we calculate the values of the earthquake and
(for a
magnitude grater than 4.8 Richter) the radio-paging seismic
alert is activated.
VRANCEA SEISMIC STATIONS
Last
earthquakes
in Romania
Regarding
Vrancea seismogen zone (one of
the most interesting seismic areas in Europe),
historical taking-downs about erthquakes
appeared over 1000 years ago, the first dated event being in 984.
During this period, 40 big earthquakes
generated important endamagements, amply described in writings
(e.g. The powerful earthquake from November 10th
1940, M 7.4 Richter, brought several damages in centre and south of
Moldavia - north-east of the country ; also,
the one from March 4th 1977, M 7.0 Richter,
is still present in the Romanians memory
because of its tragical consequences for Bucharest: over 1,500
victims,
11,300 people wounded, about 2 billion
dollars losses).
In
Vrancea, earthquakes’ epicentres are situated between
44.9-46.5 degrees northern latitude and
25.5-28.0 degrees eastern longitude
and give birth to events mostly at 60-180 km
depth (subcrustal earthquakes).
Earthquakes
born in Vrancea have tectonic origin ( as 90% of all worldwide
earthquakes), with bigger magnitudes
than other types of seismical events. These
are reasons that Romanian specialists must find all protection methods
for:
-
avoiding human life losses;
-
maintaining the continuity of socio-economic activities after
earthquakes have occurred;
-
avoiding destruction or degradation of cultural and
artistic valuable objects;
-
avoiding dangerous toxical or radioactive emanations;
-
material casualties limitation.
Therefore,
our company, FOTON 2000 SELF, accomplished an earthquake early-warning
system, integrally private,
with the declared purpose that population and important institutions in
Bucharest shall receive a warning signal before the arrival of
seismical waves generated by an earthquake in Vrancea.
EARTHQUAKE
EARLY- WARNING
SYSTEM FOR BUCHAREST
The system is based upon some idiomatic features of
Vrancea seismogen zone such as :
- spatial stationarity of
hipocentres ( very crowded, all big
earthquakes being produced only in a concentrated area );
- long epicentral
distance, about 130-150 km;
- stationarity of the
radiation models ( as conduction ).
These
features allowed us to build a simple, quick and robust system
which makes possible a
warning period of about 25-30
seconds.
When
an earthquake appears, the first wave resulted is the “p” wave
(volumetric, longitudinal and compression wave).
In the epicentre (Vrancea),
the sensors (seismometers and accelerometers) capture the first shock
and
transmit a radio signal to Bucharest,
where the decision of warning is taken if the estimated magnitude
exceeds 4.8 Richter. Ten seconds after, the “s” wave (also volumetric but
transversal wave) issues to surface and begins to march off as a
spherical wave. The
difference between the times of getting over from Vrancea to Bucharest
for the “p” and “s” wave is
always bigger than 25 seconds.
Generally
speaking, an early warning system consists of :
- a monitoring system,
containing different kinds of sensors;
- real time comunication
connections;
- main unit for
processing and converting information;
- triggering and radio
transmission of seismical alert.
Earthquakes
alerting systems are operational in Japan (since 1950, one system
is installed on japanese railways),
in Mexic (built in 1989 for
Mexico City and certified at the last big earthquake of M 7.5), Taiwan
and USA (California).
In
1999, a group of specialists within our company FOTON 2000 SELF SRL,
studied and tested out the
ideea of earthquakes real time warning especially for Bucharest.
The Early
Warning Centre, now coordinated by the Romanian
Institute for Applied Seismology,
registered and announced all earthquakes from
Vrancea bigger than M 4.8 Richter and can capture signals of energies
issued even from 16,000 km
with M 5 - 5.5
The
Monitoring system includes 3 active networks :
- RSVA,
with GEOTECH
INSTRUMENTS seismometers, for real time analogic transmission,
monitoring Vrancea;
- RAVD has
triaxial force-balanced accelerometers
from GEOSIG-SWITZERLAND
for digital transmission,
also monitoring Vrancea;
- RSAN,
with speed
and acceleration sensors for automatic transmission by GSM
equipments
(WAVECOM, FALCON, NOKIA etc), monitoring all country and used in
determination
of earthquake
parameters and study of seismical precursors.
Besides,
there are a lot of seismic stations built in teritories as
special enclosures to protect sensors,
radio equipment and back-up systems.
Seismical signals reception
and processing system includes
broadcasting receivers (YAESU), data acquisition device
(NATIONAL INSTRUMENTS), radio and GSM modems,
industrial computers (ICP), enclosures with controlled atmosphere
(RITAL) etc.
Finally, the decision
and alerting unit consists of industrial computers, special
software for spectral analysis
(LABVIEW), radio-paging broadcasters
(ZETRON), RDS encoders (AZTEC), GSM servers, back-up system etc.
Within the Romanian Institute
for Applied Seismolgy we conceived a complex monitoring system
for seismic precursors
( bioprecursors, natural
currents, infrasounds, radium emanations, magnetic fields’ distorsions
) and have big hopes that
the results of our research
will lead to a better prediction of
earthquakes.
Since the system exists, all
alerts transmitted towards customers were correct and also earthquakes
from remote
regions have been detected and relieved (
Turkey - 3 minutes & 20 seconds before ; Afghanistan - 7 minutes
& 33 seconds
before etc ).
The projects for the future
follow up the bootstrapping of the System in the Transport Industry
( railways, airports, sea ports ), the
Energetical Department, Gas and Oil Industry ( for interrupting certain
utilities
in case of important seismical events ) as
well as the generalization of the alerting system in schools,
hospitals and other public places for
prevention of accidents and panic due to an important
earthquake.
VRANCEA
ELECTROMAGNETIC MONITORING Project
smas@fotonsas.ro
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