Transcript On going development of a seismic alert management system for the

On going development of a
seismic alert management
system for the Campania region
(southern Italy)
A. Zollo(1), G. Iannaccone(2),C.Satriano(1),
E.Weber(2), M. Lancieri (1) and A. Lomax(3)
(1) Research Unit RISSC, Dip. di Scienze Fisiche, Università di Napoli Federico II
(2) Research Unit RISSC, Osservatorio Vesuviano, INGV, Napoli
(3) Anthony Lomax Scientific Software Mouans-Sartoux, France
Outline
WHY WHAT HOW
• WHY
an earthquake early warning
system in southern Italy
• WHAT
are the system architecture and
components
• HOW
does it work
SAMS: A Seismic Alert Management
System for the Campania Region
A pilot project to experiment a system for earthquake early warning and
rapid evaluation of ground motion scenarios in the Regione
Campania
WHY WHAT HOW
Objectives:
• Early-Warning and Rapid Ground shaking scenarios
• Remote control and protection of a selected target
Time Schedule:
end 2005  real-time seismic network completion
end 2006 upgrade data transmission system
Financial support:
Campania Region - Department of Civil Protection
AMRA Regional Center for Analysis and Monitoring of Environmental Risks
WHY WHAT HOW
Regional historical seismicity
Tyrrenian sea
Ground shaking during the 1980,
Irpinia Earthquake, Ms=6.9
WHY WHAT HOW
Peak accelerations &
velocities modified
from Cabanas et al.,
1998
Intensity map,
modified from De
Rubeis et al., 1996
WHY WHAT HOW
Recent earthquake activity
INGV catalogue (1981-2002), M>2.5
Rate of occurrence
Instrumental data
(Boschi et al,2003)
southern
Apennines
M>4.0
WHY WHAT HOW
M>5.0
M>6.0
Probability map of moderate to
large earthquakes (M5.5) in Italy
for the next 10 years (Cinti et al.,
G3, 2005)
1 event every
1.5 years
1 event every 4
years
1 event every
32 years
Potential targets for an EWS in
Campania region
WHY WHAT HOW
city of Napoli
4 small towns
hospitals
railways
highways
industries
gas/electric pipelines
fire stations
WHY WHAT HOW
Peculiarities / criticalities
• Moderate events (M4.5) are of interest 
social impact, loss of occupancy
• Short hypocentral distances  narrow
“early warning” windows
• Multiple rupture events  complexity/
reliability of location/magnitude
estimations
EEW seismic network & seismicity
WHY WHAT HOW
“Shake map”
network
“Early warning”
network
Network architecture
Stations
Sub-nets
WHY WHAT HOW
Local
Control
Centers
Three levels of data acquisition and
transmission:
> Stations (data loggers)
> Local Control Center (sub-nets)
> Network Control Center (Naples)
WHY WHAT HOW
Communications
2.4 GHz
54 Mbps
Data transmission system:
data logger  LCC: point-to-point
Wireless LAN bridge
LCC  LCC : backbone (SDH) / ADSL
LCC  Network center (Naples):
backbone (SDH) / ADSL
Fonctionality
WHY WHAT HOW
Local Control Center
Seismic station
• Local Control Center:
Fully automated.
Manages and processes
the sub-net data (seedlink
protocol & Earthworm
data management
system)
• Data logger: on-site
computational capabilities
(event detection,
automatic P time, peak
amplitude, P-frequency,..)
The seismic instruments
WHY WHAT HOW
Embedded Linux and Open Source Software
24-bit AD converter
Removable mass storage (2 PCMCIA slots 5Gb)
ARM720T processor, supervisory system
6 channels: 3 accelerometers + 3 seismometers (Short
Period or Broad Band)
Operational mode
1.
2.
WHY WHAT HOW
EQK
3.
STA1
4.
LCC1
5.
Event detection (STA1)
LCC1 linked to the closest
station, verifies the event
coincidence, collects and
processes P-waveform data
(time, amplitude, ..)
LCC1 estimates the
hypocenter location and
magnitude with errors (X,
DX, M, DM)
New data entries from
progressively distant
stations LCC1 updates
estimates of X,DX,M,DM
Alert notifications to endusers is sent after each updating step
Characteristic times for EEW
Latency/computational
To
T_first_P
T_S_target
time
WHY WHAT HOW
1.5 – 3.5 sec for eqk at depths of 4-16 km
60 km
80 km
100 km
16 – 18 s
22 – 24 s
28 – 30 s
3-5 sec
Source parameter estimates
Moment/Magnitude:
WHY WHAT HOW
Location:
 Trigger station order
(Voronoi cells)
 Equal differential time
(Lomax,2004)
Bagnoli (22 km)
Calitri(20 km)
Tpmax
 P and early-S max
amplitudes
 v^2 plots
 instantaneous period
TPmax (4sec)
1980 Irpinia
earthquake
Ms=6.9
Allen & Kanamori,2003
M
P-wave detection capability vs time
To + 6
3 sec
4
5
WHY WHAT HOW
At each time
step, the map
shows the
number of
stations which
would record the
first-P wave of an
earthquake
occurring at 12
km depth
beneath the
network
Evolutionary earthquake location 1/4
stations
(operational)
hypocenter
WHY WHAT HOW
Voronoi cell
boundaries
wavefront
Evolutionary earthquake location 2/4
ttB  ttA  0

“conditional”
EDT surface
volume defined
by stations
without arrivals
WHY WHAT HOW
B
A
First station
detects
arrival –
constraint
is Voronoi
cells
Evolutionary earthquake location 3/4
ttB  ttA  tnow  tA
“conditional”
EDT surface
WHY WHAT HOW
B
A
Wavefront
expands – EDT
surfaces
deform,
constraint
improves
Evolutionary earthquake location 4/4
Second station
detects arrival –
constraint
includes EDT
surface
ttB  ttA  tB  tA
“true”
EDT surface
WHY WHAT HOW
B
A
Voronoi cells of Irpinia network
WHY WHAT HOW
Voronoi cells
give the location
of the eqk
epicenter (no
depth!)
constrained by a
single station
trigger
Real time eqk location: Simulation
The plotted
quantity is
proportional to
the probability
of earthquake
location at a
given point
WHY WHAT HOW
Map at 12 km depth
Tnow=0.0 is the time of
first-P at the closest
station
WHY WHAT HOW
Real time eqk location: Simulation
Real time eqk location: Simulation
WHY WHAT HOW
Second station
detects P-arrival
WHY WHAT HOW
Real time eqk location: Simulation
WHY WHAT HOW
Real time eqk location: Simulation
WHY WHAT HOW
Real time eqk location: Simulation
WHY WHAT HOW
Real time eqk location: Simulation
WHY WHAT HOW
Real time eqk location: Simulation
WHY WHAT HOW
Real time eqk location: Simulation
WHY WHAT HOW
Real time eqk location: Simulation
WHY WHAT HOW
Real time eqk location: Simulation
Real time eqk location: Simulation
WHY WHAT HOW
P-wave arrives
at nine stations
within 2 sec
from the first-P
at the closest
station
WHY WHAT HOW
Real time eqk location: Simulation
WHY WHAT HOW
Real time eqk location: Simulation
Conclusions
A high-density, high dynamics (strong motion +
seismometers) seismic network is under installation in
Campania region for “regional” early-warning applications
The main targets are strategic infrastructures located at
distances such that expected S-wave lead time is around
20-30 sec
The network architecture is designed to have distributed
levels of data storage, communication and decisions
On going development of methods for earthquake
location, magnitude estimation. Need to provide
parameter uncertainty variation with time  engineering
structural control
An example: the evolutionary earthquake location
approach