Geophysical methods provide accurate data about the structure of the subsurface - valuable information in the field of engineering. We gather non-destructive measurement data by means of airborne geophysics, along the earth's surface as well as in or from tunnels and boreholes. These measurements are then processed and turned into three-dimensional models of the terrain from which the data was collected. Essential information is entered into geographical information systems (GIS).
In addition to the methods of gravimetry, magnetics, electromagnetics (EM), electrical resistivity tomography (ERT) or ground penetrating radar (GPR) we also apply individual specialist seismic techniques or combinations thereof. These include high resolution reflection seismic, in which we observe primary and secondary waves, refraction seismic, CMP refraction seismic, refraction tomography, analysis of surface waves (MASW), as well as seismic tomography in boreholes and hydro-acoustics (marine seismic) in bodies of water.
By using the same seismic data set but a variety of evaluation techniques, we are able to depict separate models for different exploration purposes, whereas with hybrid seismic we present a range of evaluation results in one common format. For this method it is necessary to adapt the acquisition of seismic data according to the different questions being addressed.
Electromagnetic procedures can be carried out in both the frequency domain (FEM) and time domain (TDEM). In addition to Electric Resistivity Tomography (ERT), further electrical methods include Induced Polarization (IP) Capacitive Coupled Resistivity (CCR) and the Spontaneous (self) Potential Method (SP). In the offshore sector it is possible to combine the techniques of Sidescan Sonar, Marine Seismic and Marine Electromagnetics.
To combine the measurements and results of geophysical surveys with geotechnical soil data, information must be taken directly from drilling or digging. In particular, we offer surveys utilising borehole geophysics, which provide a direct link between geophysics and geotechnics on the spot.
In the engineering sector, our geophysical investigation methods have a wide range of applications in the following areas:
- Ground surveys e.g. in areas prone to landslides, geological hazards, karst areas
- Surveys for planned transport routes
- Investigations of abandoned waste dumps, environmental geophysics
- Site and structural investigations
- Abandoned mining, detection of underground objects, ductwork, supply lines
- Permafrost regions
- Salt / potash mining, cavern construction (3D down-hole radar)
- Hydrogeological issues
In our exploration endeavours we not only rely on geophysical surveys combined with geological and geotechnical evaluations, but also utilise geodetic data for an all-round more reliable result. For example, our integrated solutions can be used to achieve better planning reliability and a smooth flow of production for your structural projects. At DMT we put together the optimum combination of exploration techniques for each individual client, placing great emphasis on finding environmentally friendly and non-destructive solutions as far as possible.