Additional works:
  • 2D/3D survey design  
  • Seismic acquisition supervision (bird dog)  
Reflection seismics
Case study: Reprocessing of seismic data for the exploration of deep thermal water

In the Bavarian Molasse basin the geothermal exploration of the Upper Jurassic Malm carbonates are planned. In order to improve the structural geologic model it is necessary to precise the depth of top Malm and to localize fault zones within the range of base Paleogene and Upper Jurassic. Especially, this refined model is necessary for the well path planning and for fixing the drilling target of the production wells.

Numerous 2D reflection seismic data were acquired in Bavaria during the 1970s and 1980s for oil and gas exploration using very different acquisition parameters. These old seismic data were now reprocessed just to a migrated time section, then time-to-depth converted with the help of existing wells, and finally selected horizons like top Aquitanian, top Chattian sands, base Chattian sands, base Paleogene and top Malm were interpreted. The reprocessing is focused on signal matching of different seismic sources, velocity analysis with small distances between analysis points and an enhancement of the vertical resolution at the target depth. By this means the risk of drilling in unprofitable parts of the Malm will be significantly reduced.

Fig. 1: 3D view of seven seismic lines with a total length of 55 km