Observatories and Research Facilities for EUropean Seismology
Volume 2, no 3 December 2000 Orfeus Newsletter


The Austrian Seismic Network

Wolfgang Lenhardt and Peter Melichar.
Central Institute for Meteorology and Geodynamics, Hohe Warte 38, A-1190 Vienna, Austria.

Short-period instrumentation - Broad-band stations -
Strong-motion stations - Analogue stations - General -

The seismic network of Austria is operated by the Department of Geophysics at the Central Institute of Meteorology and Geodynamics (ZAMG) in Vienna.

Short-period instrumentation

At the moment four digital stations in Tyrol operate at 100 Hz sampling rate. This network was established by the end of 1990 allowing a more precise evaluation of the seismic activity in the province of Tyrol of Austria. These stations are equipped with S13-sensors supplied by Teledyne® and the first data IRIS-type acquisition system Quanterra® SPCMU. The four stations are to be upgraded during 2001 with one Q4120 at the station at the Wattenberg (WTTA) and Q730's for the remaining three stations St. Quirin (SQTA), Moosalm (MOTA) and Walderalm (WATA).

Broad-band stations

Five broad-band stations with STS-2 seismometers by Streckeisen and Quanterra®-data loggers have been deployed in Austria so far. All but of two use Q380 data acquisition systems. The two exceptional stations at Hochobir (OBKA) and at the Kölnbreinsperre (KBA) are equipped with Q680-data loggers and strong-motion sensors, whereas 'KBA' is equipped with an FBA23-sensor and 'OBKA' with an 'EpiSensor' manufactured by Kinemetrics®. In addition, two stations of the Institute of Physics of the Earth (IPE) in Brno and one station of the GeoForschungsZentrum Potsdam (GFZ-Potsdam), can be utilized on-line to evaluate tremors in near-realtime. These stations use Q380 data loggers, too. Stations in Austria exhibit a mean delay-time of 10 seconds for data transmission from the seismic station to the data centre in Vienna. Data transmitted telemetrically may take a bit longer due to technical constraints. All data are accessible via 'AutoDRM' via autodrm@zamg.ac.at. All waveform data are processed and analyzed with the 'Environmental Monitoring Software Antelope' by Boulder Real Time Technologies®.

Strong-motion stations

In addition, eighteen strong-motion sensors have been deployed through recent years in Austria. Seven stations operate with SMACH SM-2-sensors from SIGSA, five of which are installed in Vienna and two in the vicinity of Wiener Neustadt - that is 40 km south of Vienna. The other eleven stations are equipped with 'FBA23'-sensors and K2 data acquisition systems manufactured by Kinemetrics®.

Analogue stations

Today, still a few analogue seismometers are in use in Austria, such as in Kremsmünster in the province of Upper Austria and the station Cobenzl in Vienna and one analogue long period instrument at the ZAMG.

General

No mobile stations are available at the ZAMG for deployment for aftershock studies and the like. Nevertheless, significant progress could be made in cooperation with the On-Site Inspection Group of the CTBTO during the aftershock sequence of the Ebreichsdorf earthquake of July 11, 2000 thus establishing the depth horizon at which the recent earthquake seems to have taken place. Although most of these events were to weak to be recorded by remote stations, clear indications regarding the focal mechanisms of the main shock and subsequent largest aftershock could be evaluated by moment tensor inversions (see web-site of the Swiss Seismological Service) and first motion studies which were conducted by the ZAMG.

Seismic stations in Austria
ISC-Code Location Latitude Longitude Elevation installed
Short period S13
MOTA Moosalm 47.3448 11.1037 1575 m 1990
SQTA St. Quirin 47.2205 11.2087 1307 m 1989
WATA Walderalm 47.3357 11.5763 1492 m 1989
WTTA Wattenberg 47.2638 11.6363 1764 m 1990
broad-band STS2
ARSA Arzberg 47.2505 15.5232 577 m 1997
DAVA Damuels 47.2867 9.8803 1602 m 1999
KBA Koelnbreinsperre 47.0784 13.3447 1721 m 1997
MOA Molln 47.8495 14.2659 572 m 1996
OBKA Hochobir 46.5092 14.5489 1075 m 1998

klick for original large figure

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