1887

Abstract

Summary

We used FD-seismic modelling to investigate paleo-doline structures in the Upper Jurassic (Malm) carbonates in the Bavarian Molasse Basin at a depth of 2 – 3 km. A high-quality 3-D seismic dataset that was shot for an area-wide supply of the district heating system of Munich shows distinct paleo-dolines, which could be isolated as geo-bodies in a variance volume. They show a vertical extent up to 500 m, while their diameter increases, from top to bottom, up to 750 m. The largest structures are connected with faults. The results of the modelling show that diffractions occur at the edges of the doline that interfere with reflections of deeper reflectors. Regardless of the migration algorithm used (including depth migration using the correct velocity model), these interferences could not be separated. Therefore distortions remain that were previously interpreted as the true extent of the dolines. In addition, we could show that the form of the dolines most likely resemble a bowl-shaped structure rather than a trapeze shape, and that the velocities are reduced inside and/or directly beneath the dolines, which causes downbending of deeper reflectors. The results confirm that dolines in the Malm carbonates represents a promising target for geothermal energy extraction.

Loading

Article metrics loading...

/content/papers/10.3997/2214-4609.201902506
2019-09-08
2020-05-29
Loading full text...

Full text loading...

References

  1. Dussel, M., Lüschen, E., Thomas, R, Agemar, T., Fritzer, T., Sieblitz, S., Huberc, B., Apfle, J. Schulz, R.
    [2016] Forecast for thermal water use from Upper Jurassic carbonates in the Munich region (South German Molasse Basin).- Geothermics60, 13–30.
    [Google Scholar]
  2. Hecht, C. & Pletl, C.
    [2015] Das Verbundprojekt GRAME - Wegweiser für eine geothemische Wärmeversorgung urbaner Ballungsräume.Geothemische Energie, Heft82, 2015/2.
    [Google Scholar]
  3. Lemcke, K.
    [1987] Zur Frage der alten Verkarstung des Malm im Untergrund des deutschen Molassebeckens und an dessen Nordwestrand. Bulletin der Vereinigung Schweiz. Petroleum-Geologen und Ingenieure, Band 53, Heft 125.
    [Google Scholar]
  4. Roeder, D. & Bachmann, G.
    [1996] Evolution, structure and petroleum geology of the German Molasse Basin.- Memoires du Museum National d’Histoire Naturelle, 1996, Vol. 170, pp. 263–284.
    [Google Scholar]
  5. Waltham, T., Bell, F. & Culshaw, M.
    [2005] Sinkholes and Subsidence - Karst and Cavernous Rocks in Engineering and Construction. - 384 p.; Berlin (Springer) - ISBN: 3-540-20725-2.
    [Google Scholar]
http://instance.metastore.ingenta.com/content/papers/10.3997/2214-4609.201902506
Loading
/content/papers/10.3997/2214-4609.201902506
Loading

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error