Observatories

DomůObservatories
Long-term observations of geophysical fields form one of the pillars of activities of the Institute of Geophysics. We record earthquakes and other seismic events in the territory of the Czech Republic and abroad, we measure temperatures at the surface and in wells, gravity and electromagnetic fields. Observed data is used to study the structure of our planet and the processes in the Earth. Data is available on the portal of the infrastructure project CzechGeo/EPOS which is supported by the Ministry of Education of the Czech Republic.

Czech regional seismic network monitors earthquakes, rockbursts and explosions in mines in the Czech Republic, in central Europe and globally. It consists of twenty broadband stations situated in the territory of the Czech Republic. Data is transferred in real time to the data center at the Institute.  Seismic service performs daily analysis of earthquakes, creates bulletins of readings of seismic stations and catalogues regional events. Digital data is provided to international data centers and serve e.g. to expedite the location process of prominent earthquakes in the world.

Local seismic network WEBNET monitors seismic activity in West Bohemia which is known for the occurance of earthquake swarms. Hot and cold mineral springs, and increased CO2 flux (Soos or Hartoušov moffetes) are other signs of the ceasing volcanic activity in the region. The dense network of seismic stations is operated by the Institute of Geophysics jointly with the Institute of Rock Structure and Mechanics.

Local seismic network REYKJANET is deployed in Reykjanes penninsula in the southeastern tip of Iceland Mainshock-aftershock sequences as well as earthquake swarms occur in this region close to the North Atlantic ridge. Stations in the REYKJANET network operate in off-line regime. Data is copied several times a year during the service visit of the stations and sent to the Institute of Geophysics in Prague for processing. The network of seismic stations is operated by the Institute of Geophysics jointly with the Institute of Rock Structure and Mechanics.

MOBNET is a pool of seismic stations installed temporarily in tectonically different regions in the frame of collaborative seismic experiments. The pool consists of 65 portable units. About half of the seismometers of the pool are short period Lennartz Le-3D sensors, the rest are tree-component broad-band seismometers – Streckeisen (STS-2) and Guralp (CMG-3T, CMG-3ESP, CMG-40T). GAIA data acquisition systems work mostly in offline regime. MOBNET stations have been deployed in international passive seismic projects RETREAT, LAPNET, PASSEQ, MOSAIC, BOHEMA and AlpArray.

Geothermal network GeoCLIMANET consists of three stations in the Czech Republic (Praha, Kocelovice, Svojšice), one station in Portugal (Evora-Caravelinha) and one station in Slovenia (Malence). All the stations monitor air and soil temperatures at different depth levels between the surface and a depth of 1 m. Except Svojšice, all stations measure also bedrock temperatures at depths between 40 m to 190 m. The observed data is used for the analysis of the air – ground surface temperature coupling and the heat transfer in different climatic, pedological and environmental conditions.
National geomagnetic observatory Budkov is situated in the southern Bohemia, in the district of Prachatice. Since 1996 the observatory meets high international standards and is a certified observatory of the international network INTERMAGNET. The observatory is equipped with two digital magnetometers with 3-axis ferromagnetic fluxgate sensors and with Bobrov type variometers. Data is uploaded to the Geomagnetic Information Node in Edinburgh. Variation measurements are completed weekly by absolute measurements of the geomagnetic field, carried out by a non-magnetic theodolite CARL – ZEISS equipped with a single-axis Bartington fluxgate sensor.

In the geodynamic networks CZET, WEBGEODYN and GREVOLCAN we perform measurements of the earth tides at several tiltmeter stations, precise measurements of surface displacements by the GNSS technology, and observations of the earth’s gravity field and its temporal variations. As well, we continuously record changes of groundwater level at wells. Beside these permanent observations we investigate location, composition and activity of volcanic structures in West Bohemia, Bavaria and Greece.

In the Tectonic modelling laboratory (TML), we perform physical analog experiments to investigate large-scale and long-term geological processes, such as orogenic buckling, salt tectonics in rift basins and fold-and-thrust-belts as well as magmatic plumbing systems. Our laboratory infrastructure consists of a number of modelling devices to simulate tectonic shortening and extension, pure and simple shear strain, magmatic intrusions and eruptions as well as sediment deposition systems. To record deformation and strain patterns, our laboratory is equipped with modern strain quantification techniques such as a 3D digital image correlation system and anisotropy of magnetic susceptibility generated by magnetic particles aligned in the deformed material.