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Our company does use a whole portfolio of near-surface geophysical methods. See details below.
• Seismics
• Geoelectrics
• Gravimetry
• Magnetometry
• Radiometry
Main office
Přístavní 24
170 00, Praha 7
tel./fax 266712779
ISO 9001:2008
Ministry of the Environment - geophysical works
Ministry of the Environment - geological survey
Ministry of Transport - geotechnical survey via geophysical methods
Ministry of Transport - corrosion survey
Seismic methods are based on registering seismic waves behavior and their velocities. They can reflect, refract or diffract. Increasing velocities generally indicate more solid and harder environment. According to velocities we are able to calculate elastic moduli of rocks and other physical parameters as well.
Gravimetry is based on observing of the gravity field and changes in it. After substracting the regional influences we get so called residual anomalies. Negative residual anomalies indicate lack of volume or density (increasing porosity, cavities, voids etc.). Positive anomalies mean increasing density, i.e. elevation of the bedrock.
Geomagnetic field´s anomalies are caused by presence of rocks or objects with anomalous magnetic properties. Magnetometry is being used for detecting undergroud objects with different magnetic properties (iron, steel...), for mapping different lithological types (according to magnetic susceptibility changes), localizing old landfills material (barrels, drums...), unexploded ordnance or buried pipelines, wires etc.
Geoelectrics is generally divided in two branches - DC and AC (electromagnetic) methods. Typically we measure apparent resisitivity of the environment, permittivity or spontaneous (natural) potentials. According to these parameters we can interpret changes in water saturation, state of stress, presence of fracture zones, movement of contaminants in the groundwater or solve issues in archeology, roads, railways etc.
Radiometry is based on observing the distribution of natural and artifical sources of radioactivity. Measurements of radioactivity can be ground-based, airborne or in drillholes. Typical applications are mapping of radioactive ores, localizing the fracture zones or radon risk´s assessment.