nnsn-realtime by hedongchenchen

VIEWS: 56 PAGES: 30

									   Norwegian National Seismic
   Network realtime monitoring
         Terje Utheim, Jose Ojeda and Jens Havskov




                                  Presented at
                             International workshop
SEISMICITY AND SEISMOLOGICAL OBSERVATIONS OF BALTIC SEA REGION AND ADJACENT
                                 TERRITORIES
                             10–12 September, 2007
                              VILNIUS, Lithuania,
Stations in
  NNSN

Norwegian
National Seismic
Network and
other seismic
stations in
Norway. Blue
symbols are
NNSN stations
and red are
NORSAR arrays.
The station JMIC
is operated by
NORSAR.
        Typical NNSN recording system using
                    SEISLOG
                                                       Communication




         Sensor          Analog to
                          Digital              Computer              Data storage
          input
                         converter




                                                            Power
                                      GPS
                                                            supply



The signal is sent to the anlog to digital converter which converts the signal to a
digital signal. It is then transferred to a computer, where it is recorded and stored.
Via internet, the signal are sent from there to Bergen. The SEISLOG system runs
in QNX, Windows and Linux. NNSN also connects to GSN stations.
         Communication for NNSN



Fixed internet, free
Internt with ADSL, cheap
Interent with ISDN, expensive
Internet with mobile phone (3G, Edge or GPRS), medium price
Current NNSN data collection: SEISNET
            NNSN real time system


Data in realtime to Bergen
Improve network monitoring
Do triggering centrally instead of locallly
Use well proven public domain software
Develop new software for real time systems and make it public
domain

Use protocols LISS and/or SEEDlink
                      What is LISS


Made for installations and maintenance of the Global Seismic
Network and collection and distribution of data produced by these
stations.

Sends out live data from the Global Seismic Network
Albuquerque Seismological Lab is part of USGS and responsable
Protocol: one-way only

Data transmitted in standardized MiniSeed format 512 byte blocks.

32 byte integer, Steim1 or Steim2 compression
GSN stations
         What is SEEDLINK

Similar to LISS with extra headers added
Capable of 2 way communication
Retransmission and error correction
SEEDLINK server made by GFZ-Potsdam and intgrated in their
SEISCOMP acquisition system
Used for GEOFON network and others
Geofon – Worldwide




                     Geofon –
                     Worldwide
                                 SEISLOG Linux

                                                                       SeisComp

                                                                      Acquisition
                        SEISLOG                    SRV
                                                                      Plugin LISS
                        Data-structure         LISS Server
   RD3                                                                 SeedLink
                        Shared Memory         512 byte blocks
 EarthData              Driver Digitizer                              Earthworm
                                                MiniSEED
                                              Steim 1 Compr.
  SADC24                                                               LISSPLOT


On SEISLOG Windows and SEISLOG Linux,              MiniSEED blocks can be requested
SEISAN can be installed, and data can be           on localhost or remotely via
recorded directly into the SEISAN data base        Internet.
for local processing.                              The LISS protocol is one-way only.
                       Software
All SEISLOG Linux routines are written in C

Software identical for desktop PC, laptop and embedded

Utilities for monitoring and graphics are written as clients
communicating with SEISLOG server over sockets

Ringbuffer and event files written in MiniSEED format

SEISAN S-files written in SEISAN data base structure

Waveform data written in SEISAN data base structure

Server function emulates LISS server (transmission of
512 byte MiniSEED blocks over Internet)
                   Embedded ?
The computer used is a single-board micro-computer

The computer will normally not have keyboard, monitor
or mass storage such as standard hard disks connected

The operating system is pre-installed in flash memory
and is a stripped version of standard distributions of
Linux to save memory

Application software SEISLOG, also stored in flash

Communication with the computer is done through a
console serial port or through Ethernet with a terminal
emulator
TS-7260




 Cost: $ 180
            Embedded SEISLOG Linux



                      TS-7260 200 MHz
                       32 Mb SDRAM
                         32 Mb Flash
                           Ethernet
                       3 x Serial ports
                           2 x USB
                      Different options:
Digitizer              64 Mb SDRAM
                          Serial lines     USB Hardisk
              RS232         PC104

                      Linux and Seislog     USB pen
                         embedded




                          Ethernet
SEISLOG Linux embedded + Earth Data
              digitizer
SARA embedded Linux recorder with geophones




                  Cost: 1900 EU
Broad band sensor versus 4.5 Hz geophone




                        Noise spectrum for 4.5 Hz
                        SARA recorder
NNSN communication
     Software for real time monitoring

Real time plot: RTNET and LISSPLOT
Monitoring of remote field stations: RTMON and
NETMON
REAL time network detection: EARTHWORM,
SEISCOMP and RTDET

All software is public domain
  RTNET real time plot




Plot uses SEEDLINK as input
     RTNET real time plot filtered




Raw signals                 Signals filtered 2-8 Hz
RTNET single trace plotting
               LISSPLOT




Helicorder type real time plot using LISS as input
              Monitor program RTMON




Real time monitoring stations using SEEDLINK. The detection program
reads data from a Seedlink server. The red line indicates a trigger and LAT
is latency relative to real time.
NETMON monitoring of SEISLOG stations




      Bar lengths show station uptime since last start
EARTHWORM helicorder plot
   Event detection RTDET




Event detected by RTDE. Uses SEEDLINK as input.
                NNSN real-time data acquisition
    BERB                                             Solaris
Seislog Linux
                         Linux PC
                    SeisComp/SeedLink              EarthWorm
 LISS-server
  SeedLink                                    Continuous 1-hour files
                      Ringbuffer system
    BER
                       Continuous Data             Trigger files
Seislog Win
LISS-server            Re-transmission               Heliplot

   KONO
                            Heliplot
   USGS
LISS-server           Seisgram monitor
                      Plots of selected
    LRW                 components

    BGS
  SeedLink


     XXX
Seislog Linux
                                                    SEISAN
PC+Embedded
                    Data sharing with other        DATA-BASE
 LISS-server
                    SeedLink servers, local
                          or remote.
    YYY
Seislog Win
LISS-server                                          SEISAN
             NNSN experience

15 stations from Norway, Finland and the UK are
monitored
EARTHWORM has triggered reliably but real
time station density is too low to give good
coverage in parts of the region
RTDET seems to trigger like EARTHWORM, but
more testing needed
The real time graphical monitoring is very usfull
for daily check of the stations

								
To top