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| Titel |
Formation of large collapse dolines: A three-dimensional numerical perspective |
| VerfasserIn |
T. Hiller, G. Kaufmann, D. Romanov, F. Grabrovsek |
| Konferenz |
EGU General Assembly 2012
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 14 (2012) |
| Datensatznummer |
250059665
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| Zusammenfassung |
| Collapse dolines are a prominent surface expression of karst regions. They can reach diameters from one meter to several hundred meters, and their depth range varies between a few meters and several hundred meters. Field studies reveal that several of these structures originate from the enlargement of fissures and bedding partings in the sub-surface through the removal of calcite by CO2-enriched water, and the subsequent collapse of these enlarged voids, which cause mechanical breakdown of the overburden.
We use the three-dimensional numerical modelling tool KARSTAQUIFER to simulate the temporal evolution of a zone of fractures along the water table. Enlarged fractures can collapse, once a critical width is reached, thus initiating the breakdown and the formation of a collapse doline. The repeated collapse of the fractures keeps the removal rate of calcite high and thus provides an effective process to form a large collapsed zone, which then can migrate towards the karst surface and finally cause a collapse doline. |
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