The Conrad Observatory is part of the Austrian Seismological Network as it hosts the seismological station CONA. The network is operated by the Austrian Seismological Service (ZAMG) and responsible for fast and reliable recording and documentation of earthquakes in Austria and worldwide.

Seismology is the scientific study of the  origin, temporal and spatial distribution, measurement and consequences of earthquakes. Earthquakes are tremors in the Earth's crust, which can be triggered by a multitude of causes. Only if the origin is known can measures be set to minimize risks. Mechanisms often reveal themselves already in seismograms (Fig. 1) - recordings by seismometers, which are instruments that measure ground motions.

The recordings often show typical signatures providing information on the origin of individual earthquakes. Furthermore, conclusions about the Earth's interior can be drawn by interpreting these records. Therefore, the research of earthquakes contributes to our understanding of geological structures and the Earth's composition. Generally, two main groups of earthquakes can be distinguished: (1) Natural earthquakes: Tectonic and volcanic earthquakes, as well as earthquakes due to cave-ins, e.g. sinkholes, and impacts, e.g. meteorites, are counted amongst these; and (2) Induced earthquakes: This group summarizes all ground tremors caused by human activity and anthropogenic impact on the environment, e.g. earthquakes related to mining of natural resources, construction of dams, waste injections into wells, and blasting operations.


In 1895 the severe earthquake in Laibach (Ljubljana, Slovenia) led to the foundation of the Austrian Seismological Service by the Austrian Academy of Sciences and the systematic installation of several seismological stations in the Austro-Hungarian Empire. For this purpose, pendulums to register ground movements were originally used in Vienna (Austria), Trieste (Italy), Laibach (Slovenia), Kremsmünster (Austria) and Lemberg (Lviv, Ukraine). Incidentally, the seismological station in Kremsmünster has continually been in use since 1898 and is therefore the oldest seismological station in Austria. In contrast, in Vienna a seismological station was only installed in mid-1903 at the k.k. Zentralanstalt für Meteorologie und Erdmagnetismus (Hohe Warte). The following year, in 1904, the Austrian Seismological Service was officially incorporated into the responsibilities the k.k. Zentralanstalt. In the same year Victor Conrad, namesake of the Conrad Observatory, was appointed Head of the Seismological Service. One of his many contributions to seismology was the development of the Conrad pendulum, which was specially designed to record local earthquakes. The pendulum served as a seismometer between 1908 and 1981 in Austria. Today the Austrian Seismological Service maintains not only a large number of seismological stations in Austria, but also accesses data from stations in our neighboring countries thanks to mutual agreements between relevant institutions. In Austria two systems are in use: broad-band stations (eg. CONA) which can register earthquakes over both short and long distance, and strong-motion stations for recording stronger earthquakes with strong ground movements close to an epicenter. Additionally, few short-period stations are also still in use.

 


In 2002 the first seismological broad-band measurement was performed at the Conrad Observatory, which became part of the Austrian Seismological Network with the international station code of CONA (Fig. 2). In 2007 a free field broad-band station CSNA (Fig. 3) was commissioned outside of the seismo-gravimetric observatory. The Conrad Observatory serves as the master station as well as research center for instrumentation and comparison of signals recorded with different seismometer types. The excellent laboratory facilities offer the infrastructure and instrumentation to carry out short- and long-term experiments. The Conrad Observatory also provide expertise in testing and training for seismic instrumentation, data acquisition systems and site preparation.


References
Wolfgang Lenhardt (2010) The Seismic Network in Austria. COBS Journal 2010. (link)
Alfons Eckstaller, T. Fromm, S. Huber (2010) Testing hardware and software for the local seismographic network at Neumayer Station, Antarctica - lessons about Antelope software. COBS Journal 2010. (link)
Wolfgang A. Lenhardt, Peter Melichar, Rudolf Steiner und Nikolaus Horn (2001) Erdbebenstationen in Österreich. In: Christa Hammerl, Wolfgang Lenhardt, Reinhold Steinacker, Peter Steinhauser (Hrsg.): Die Zentralanstalt für Meteorologie und Geodynamik 1851 – 2001. Leykam.

Related Literature
Conrad, V. (1909) Beschreibung des seismischen Observatoriums der k. k. Zentralanstalt für Meteorologie und Geodynamik in Wien. In: Mitteilungen der Erdbeben-Kommision der kaiserl. Akad. d. Wissensch. in Wien, Neue Folge, 1900-1912, No. XXXIII, 1-28.
Conrad, V. (1910) Ein einfaches Instrument für seismische Stationen in habituellen Stossgebieten. Beträge zur Geophysik, Bd.X, Heft 3, 157-160.
Kreil, K. (1855) Über einen neuen Erdbebenmesser. Sitzungsber. d. k. Akad. d. Wiss., mathem.-naturwiss. Cl., XV, Heft I-III, 370-371.
Wiechert, E. (1903) Ein astatisches Pendel hoher Empfindlichkeit zur mechanischen Registrierung von Erdbeben. Gerl. Beiträge zur Geophysik, VI, 435-460 and Phys. Zeitschr., 4, 821-829.

Suggested Literature
Modern Global Seismology (1995) T. Lay, T.C. Wallace, 521 S., Academic Press.
Quantitative Seismology (2009) K. Aki, P.G. Richards, 700 S., University Science Books.
Of Poles and Zeros, Fundamentals of Digital Seismology (2001) F. Scherbaum, 280 S., Springer.
The Mechanics of Earthquakes and Faulting (2002) C.H. Scholz, 496 S., Cambridge University Press.

Suggested Online Material

Live – Seismogram CONA
What should I do when there is an earthquake?: ZAMG Erdbeben Verhaltensratgeber (German only)
For more information on earthquakes follow the link: ZAMG Geophysik Erdbeben Informationsmaterial (German only)
ZAMG Forschungsheft zum Thema Erdbeben für Kinder und Jugendliche (German only)
USGS Earthquake Hazards Program – Learn
IRIS Incorporated Research Institutions for Seismology – Education and Public Outreach

Definitions
Seismological stations are used to observe and record ground motions, which can be triggered by earthquakes, volcanic activity, explosions, etc. These observations and recordings are used to identify the cause and consequence for the nearby population. In order to ensure high quality of the measurements the locations of these stations have to be selected very carefully to minimize background noise, e.g. a location like the Conrad Observatory.

The Austrian Seismological Service has to fulfill multiple duties including the maintenance of a station network in order to record all seismological events in Austria in addition to pinpointing their location and to provide an interpretation. Furthermore, registration and documentation of earthquakes perceived by the Austrian population are among these tasks as well as the support of public crisis management in account of possible effects. This leads to the responsibility to prepare a compilation of an earthquake risk classification on the basis of historical and recently recorded earthquakes. Additional tasks include international communication and exchange of seismological data, as well as participation in monitoring the compliance of the nuclear-test-ban-treaty, just to name a few.