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Seismics

Seismics base on measuring travel times of seismic waves, that propagate through subsurface with material specific velocities. The seismic waves are excited by seismic sources as hammer, accelerated weight drop or explosives.

Sample applications:

  • geological structure (weather layer, aquifers, sediment layers, basis of bedrock)
  • parameter of rock and soil (porosity, density, rock classification, characteristic values, earthquake protection)
  • fault investigation (gaps, fracture zones)
  • detection of caves, banks, objects

Investigation depth: 10 meter up to 1000s of meters

Methodically, according to the problem, refraction seismics or reflexion seismics is applied.

Principle of refraction seismics

At geological layer bounderies and all other discontinuities in subsurface, where a change of material occurs, the waves are refracted (broken) and reflected. They can be recorded with vibration measurement devices (geophones) spread along a line.





Resulting plot of a discontinuity

Result of a fault investigation

The travel times and amplitudes are displayed in a so called seismogram. After an accurate data processing, a seismic image of the subsoil turns out therefrom. From this, a geological model can be interpreted. For special investigations, horizontal geophones, a 9 component borehole geophone, and the especially developed FAST 24 system are available.