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The Broadband
Digital Seismic
Principles of the New Broadband Digital Seismic Network at Kandilli Observatory A new technological and conceptual approach to seismic network design is necessary to fulfill current and future needs. The New Kandilli Observatory Broadband Digital Seismic Network will include the latest in seismic instrumentation deployed evenly throughout the country thus providing homogeneous and consistent data. This network of seismic stations will also require a central real-time data processing, archiving and data distribution infrastructure. This high quality digital seismic data will be used both for real-time emergency operations and scientific research. Real Time Operations
Scientific Aims
Seismic Network Design Criteria One of the primary goals of the Broadband Project is to
install at least 1 seismic station at every 150- Click on each station mark for Specific Station
Information Seismic Instrumentation and Station Design One of the major improvements underway is the installation of
broadband seismic sensors which can record local, regional and
teleseismic earthquakes. Each broadband seismic sensor will be able to
record, at minimum, up to a 20s seismic wave period. This minimum criteria is
necessary in order to calculate Surface Wave Magnitudes (Ms). However, the
majority of the broadband seismic sensors will be able to record up to a 300
s period. This “broadband” capability will make the data useful to other
applications such as earthquake source and structure studies which are
crucial in understanding All newly
designed broadband seismic stations now have:
Real-Time Data Telecommunication At present the majority of the stations are transmitting data
via dedicated lease lines which utilizes the telephone communications
infrastructure. This is required in order to guarantee the data flow for
real-time monitoring purposes. However, internet is becoming an
alternative since it is economical and also provides a communication
infrastructure with a high level of redundancy. Such Internet connected broadband
stations have already been cooperatively installed at universities in Telecommunication currently being used at each station. Real-Time Seismic Data Processing
and Seismic Since October of 2001, real-time processing of all incoming
seismic data to Kandilli Observatory has been achieved by using the
comprehensive Kandilli Observatory Real-Time Automated
Seismic Data Processing System, designed and maintained by the Broadband
Group. This complete system uses Earthworm
as its core real-time data processor. The Earthworm software suite was
originally developed and is continually supported by the United States
Geological Survey (USGS)
and other cooperative academic institutions throughout the world. This system
is currently in use throughout all major seismic networks in the Seismic All digital stations are monitored on a daily basis for data recovery percentages, station timing (GPS) and power supply (voltage). This information is then formed into a Daily State of Health (DSOH) reports which are distributed via e-mail to the real-time system managers, network planners/de-buggers and decision makers. In addition to DSOH reports Event State of Health (ESOH) reports are created when a large enough teleseism sweeps across the entire network. In this case the trace data from both digital and analog stations are analyzed for quality thus creating a more complete picture of overall network performance. These internal reports are distributed to all members within Kandilli Observatory that request them. Finally semi annual and annual broadband continuous data recovery reports are created and distributed to network operators, planners and decision makers. Though routine in nature these combined reports provide vital information to keep the proper people informed about daily network problems/successes. Over the long term they provide valuable quantitative information necessary for overall operations evaluation that can be used for sensible future planning. Data Archiving and Distribution The data archiving and distribution system currently managed by the Broadband Group is a sub-system of the Kandilli Observatory Real-Time Automated Seismic Data Processing System. Continuous and auto-event based data collected in real-time are automatically backed up to 2 mirrored Linux PCs in SAC Format. The most recent 6 months of data remains on the hard-drive and is available via FTP within the Kandilli Campus. At the beginning of each month the most recent months data is written to 2 copies of DDS-3 DAT tapes for long term archiving. Future plans include the installation of an Auto Data Request Manager (AutoDRM) which will allow everybody direct automated access to our high quality digital data via email request. Real-Time International Data Exchange Location accuracy becomes an issue when events are
located outside national networks, e.g., border regions. This is particularly
relevant to Since taking responsibility for the digital station network operations at Kandilli Observatory in March of 2003 thirteen completely re-designed broadband stations were installed throughout Turkey (see map and section above on “Seismic Instrumentation and Station Design”). The general plan is to increase the number of broadband stations to 40 by the end of 2005. Many of the new stations will use infrastructure (buildings, power and phone line connections) belonging to the currently operating analog short period stations. As the number of digital stations and thus incoming data volume grows new design innovations to the Kandilli Observatory Real-Time Automated Seismic Data Processing System are a constant necessity to ensure central processing efficiency and robustness. Such design innovations are ongoing. M. Aktar and H. Karabulut, National Seismic Network of
Turkey: Design and Implementation, PDF (for
Turkish) Active Broadband Project Team Members Hayrullah Karabulut Project Manager
Other Contributors
Sotfware Development -
Broadband Group Modified EARTHWORM module naqs2ew - ZIP - RAR - TXT (Notes)
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Hazırlayan: Doğan AKSARI Telif Hakki
Bogaziçi Üniversitesi, Kandilli Rasathanesi ve Deprem Arastirma Enstitüsü Jeofizik
Anabilim Dalı 34680 ,
Çengelköy, |
