Evaluation of susceptibility for terrain collapse and subsidence in karst areas, municipality of Iraquara, Chapada Diamantina (BA), Brazil
The morphological evolution of the karstic systems is associated with a set of physical and chemical processes, triggered by the dissolution of the rocks, related to percolation of groundwater and surface water, which consequently open underground voids and carve out peculiar forms of relief. Due to...
| Autores: | , , , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2018 |
| País: | Brasil |
| Institución: | Universidade Federal de Minas Gerais (UFMG) |
| Repositorio: | Repositório Institucional da UFMG |
| Idioma: | portugués |
| OAI Identifier: | oai:repositorio.ufmg.br:1843/52111 |
| Acceso en línea: | https://doi.org/10.1007/s12665-018-7769-8 http://hdl.handle.net/1843/52111 https://orcid.org/0000-0002-7912-3323 https://orcid.org/0000-0001-7183-0368 https://orcid.org/0000-0003-4015-3370 https://orcid.org/0000-0003-3913-3735 https://orcid.org/0000-0001-5268-3999 https://orcid.org/0000-0003-0674-4070 |
| Access Level: | acceso abierto |
| Palabra clave: | Karst Carbonate rocks Chapada Diamantina Collapse and subsidence Brazil Brasil Rochas carbonáticas |
| Sumario: | The morphological evolution of the karstic systems is associated with a set of physical and chemical processes, triggered by the dissolution of the rocks, related to percolation of groundwater and surface water, which consequently open underground voids and carve out peculiar forms of relief. Due to environmental and geotechnical aspects, this system is naturally more fragile and vulnerable than other natural systems and, therefore, has increasingly received the attention of the scientific community over the past decades. The objective of the study was to delimit zones with varying degrees of susceptibility for collapses and subsidence of sinkholes in the municipality of Iraquara, Chapada Diamantina (BA), Brazil, and to understand their geological and morphological determinant factors. Geological data, karst phenomenon map, and visual analysis in the field were used to categorize zones with different types of susceptibilities to the nucleation of new sinkholes based on a Hazard Index. This index was defined from the sum of geological hazard factors, lineament density, and sinkhole density. The areas that presented the highest susceptibility for terrain collapse and subsidence corresponded to regions where carbon‑ ate rocks outcrop, with high density of photolineaments and 2.62 sinkholes/km2. Processes associated with terrain collapse and subsidence in karst areas consisted of a combination of various factors, hindering precise predictions. However, zones of different types of susceptibilities to terrain collapse and subsidence can be delimited when the relationships between these processes and their factors are understood. The Hazard Index proposed does not provide quantitative values for the probability of hazard susceptibility, but rather indicates areas that are more susceptible to terrain subsidence and collapse. |
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