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| Titel |
Fault analysis as part of urban geothermal exploration in the German Molasse Basin around Munich |
| VerfasserIn |
Jennifer Ziesch, David C. Tanner, Sabine Hanstein, Hermann Buness, Charlotte M. Krawczyk, Rüdiger Thomas |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250148167
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| Publikation (Nr.) |
 EGU/EGU2017-12401.pdf |
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| Zusammenfassung |
| Faults play an essential role in geothermal exploration. The prediction of potential fluid
pathways in urban Munich has been started with the interpretation of a 3-D seismic survey
(170 km2) that was acquired during the winter of 2015/2016 in Munich (Germany) within the
Bavarian Molasse Basin. As a part of the research project GeoParaMoL*, we focus on the
structural interpretation and retro-deformation analysis to detect sub-seismic structures within
the reservoir and overburden. We explore the hydrothermal Malm carbonate reservoir (at a
depth of ~3 km) as a source of deep geothermal energy and the overburden of Tertiary
Molasse sediments.
The stratigraphic horizons, Top Aquitan, Top Chatt, Top Bausteinschichten, Top
Lithothamnien limestone (Top Eocene), Top and Base Malm (Upper Jurassic), together with
the detailed interpretation of the faults in the study area are used to construct a 3-D geological
model. The study area is characterised by synthetic normal faults that strike parallel
to the alpine front. Most major faults were active from Upper Jurassic up to the
Miocene. The Munich Fault, which belongs to the Markt-Schwabener Lineament, has a
maximum vertical offset of 350 metres in the central part, and contrary to previous
interpretation based on 2-D seismic, this fault dies out in the eastern part of the
area.
The south-eastern part of the study area is dominated by a very complex fault system. Three
faults that were previously detected in a smaller 3-D seismic survey at Unterhaching, to the
south of the study area, with strike directions of 25°, 45° and 70° (Lüschen et al. 2014),
were followed in to the new 3-D seismic survey interpretation. Particularly noticeable
are relay ramps and horst/graben structures. The fault with a strike of 25° ends in
three big sinkholes with a maximum vertical offset of 60 metres. We interpret this
special structure as fault tip horsetail-structure, which caused a large amount of
sub-seismic deformation. Consequently, this area could be characterised by increased fluid
flow.
This detailed understanding of the structural development and regional tectonics of the study
area will guide the subsequent determination of potential fluid pathways in the new 3-D
subsurface model of urban Munich.
This project is funded by the Federal Ministry for Economic Affairs and Energy
(BMWi).
Lüschen, E., Wolfgramm, M., Fritzer, T., Dussel, M., Thomas, R. & Schulz, R. (2014): 3D
seismic survey explores geothermal targets for reservoir characterization at Unterhaching,
Munich, Germany, Geothermics, 50, 167-179.
* https://www.liag-hannover.de/en/fsp/ge/geoparamol.html |
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