Geohysical Institute, Prague, Czech Republic. November 9 - 12, 1998
Torild van Eck
Introduction - Program and Items -
ORFEUS, Royal Netherlands Meteorological Institute,
De Bilt, Netherlands
ORFEUS organized and sponsored in
November 1998 a workshop in Prague at the
Geophysical Institute of the Academy of
Sciences of the Czech Republic (ASCR):
"Installation and operation of broad-band seismograph stations".
The workshop was an initiative from ORFEUS's
Working Group 1 and
Working Group 2.
Jan Zednik, Axel Plesinger and Hana Kochova, all from the Geophysical Institute,
stood for the local organisation.
participants and lecturers from 18 countries met during four days.
Below follows a (very) short summary of the lectures in the program
program. A number of
will or are already available. Much of the practical information presented will be made
available within Working Group 2.
- Winfried Hanka (Geofon),
VBB systems and networks - introductory overview
Broad-band seismometer developments: SRO-derivatives - KS26000 and KS54000 ; STS2 ; 6MG-3T.
New developments: FBS-3 (SSB Beijing) ; JCZ-1 (SSB Wuhan) ; PMD Scientific Inc (USA).
Dataloggers: gain ranging (12 bits) real 24 bit technology and 24 bit Delta-sigma technology.
New developments: Earth Data PR2400 (real 24 bit technology)
Federation of Digital Seismograph Networks (FDSN), GEOSCOPE, IRIS, GRSN, USNSN, GEOFON, etc.
Seismometer installation. with Geofon's and GRSN's shielding techniques. Vaults. Datalogger and
SeisComP (see software) concept
- Damiano Pesaresi (MedNet),
Installation & maintenance of VBB station
Seismometer installation, noise and temperature isolation.
Data Acquisition (DAQ) Systems - MedNet, like GEOFON operates Quanterra - GPS
(Satelite) communication, mobile phone and wireless Internet: VSAT, INMARSAT
Practical operational procedures and station examples.
- Erhard Wielandt (Stuttgart),
Force-balance seismometers - theory & calibration
Principle of inertial seismometers (for example the STS-1 and STS-2).
Poles and Zeros description of the system response
Relative (electrical) calibration - software available at Stuttgart University
Absolute (mechanical) calibration - presentation of effective (poor man's) method.
- Reinoud Sleeman (ORFEUS),
AutoDRM: concept and implementation
presentation of AutoDRM for potential operators and users.
- Axel Plesinger (GI ASCR, Prague),
Transfer functions, system responses & calibration headers
Theory of transfer functions, the Poles and Zeros description of the transfer function.
Fourier, Laplace transform, Z-transforms. Amplitude and phase response, Minimum-phase systems.
IIR (Infinite Impuls Response) and FIR (Finite Impuls Response) filters,
causal and acausal filters.
Calibration, MatLab based software available.
- Frank Scherbaum (Potsdam),
High resolution AD conversion & FIR filters
FIR filters, principles of Sigma-Delta modulators, relevancy of accurate filtering
(deconvolution) procedures, i.e. ground motion recovery.
Stable deconvolution using minimum and maximum phase filters.
Filtering and educational software available.
- Roderick Stewart (CTBTO/IMS),
CTBTO: International Monitoring System and Global Communication
Presentation and explanation of the CTBT Organisation.
Presentation activities of the IMS, discussions about the interaction between
IMS (who bears the responsibility for verifying the systems) and the
- Bernard Dost (ORFEUS) and
Jan Zednik (GI ASCR, Prague),
Data archiving and exchange, formats & format conversion
Overview SEED (Standard for the Exchange of Earthquake Data),
Data exchange facilities (AutoDRM, ftp, Internet).
Format conversion (available software) overview.
- Klaus Stammler (Gräfenberg),
Basic data handling and analysis software
Presentation of and hands-on training with Seismic Handler (SH),
an (array) data analysis package used at Gräfenberg.
- Neil Spriggs (Nanometrics),
Satelite communication in seismology
The potential of satelite communication: Ku-band technologies, presentation of Libra
- Dan Harvey (Boulder Real Time Technologies, Inc.),
The Lodore Broadband Array
Practical aspects of the (Kinemetrics) installation of a BB array with different
remote data users. Presentation of the Antilope Seismic Information System (ASIS - a
further development of DataScope).
- Rhett Butler (IRIS),
A Broadband Seismic Station on the Sea Floor: The Hawaii-2 Observatory
Interesting 15 minutes summary video of the installation of a Deep Sea station
connected to an old Pacific telephone cable for communication.
- Genevieve Roult (GEOSCOPE),
an Experiment of Sea Floor Observatory
Presentation on the French Ocean Bottom Observatories.
ORFEUS is planning a similar workshop with emphasis on
"Installation, operation, data processing in experiments involving mobile
(broad-band) seismic equipment" for autumn 1999.
The planning of another workshop
"Seismological software development with emphasis on Java"
will be discussed at the IUGG99 in Birmingham. Any suggestions with
regard to these plans are appreciated.
ORFEUS received much more applications for the 1998 ORFEUS workshop, however,
only a limited number of people could be admitted. Please, let us know if you
are interested in a repeat of the ORFEUS 1998 workshop.
( send an email to Torild van Eck).