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| Titel |
Hiatuses and changes in clastic versus carbonate facies in Holocene riverine tufa deposits from the Iberian Range (Spain) |
| VerfasserIn |
Juan Vázquez-Navarro, Jose Eugenio Ortiz, Trinidad de Torres, Angel Vázquez |
| Konferenz |
EGU General Assembly 2014
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250099919
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| Publikation (Nr.) |
 EGU/EGU2014-15771.pdf |
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| Zusammenfassung |
| Calcareous tufa deposits are a type of terrestrial limestone formed by the precipitation
of carbonate minerals in water bodies at ambient temperature. They represent an
outstanding record of continental paleo-environmental information, as their frequent
presence during interglacial periods of the European geological record is the result of
warmer and more humid climatic conditions -. These climate phases favoured the
development of forest vegetation in contrast to the steppe biome, rather predominant during
glacial/stadial times. Commonly tufa deposits are selected to conduct detailed paleoclimatic
reconstructions, using multiproxy approaches with: malacological and pollen spectra, trace
elements, and δ18O and δ13C of calcite. Additionally, they can preserve a better
record of the erosion episodes in relation to other fluvial sediments, constituting
a type of non-continuous sedimentary archive. We document here the existence
of ten previously-unknown Holocene tufa riverine deposits belonging to a wide
area in the central and eastern Iberian Range (Spain). In order to establish their
stratigraphy and chronology, these have been dated by means of the aminoacid
racemization method, applied on ostracod valves extracted from carbonate facies.
Geomorphologic, sedimentologic, and chronologic surveys have been carried out, having as a
result a database that will be provided with the aim to compare its sedimentary
environments and the synchrony of regional sedimentation and erosion. The evolution of
these tufa sequences is described with special attention to the transitions between
different sedimentary phases from carbonates to clastic. Climate drivers, rather than
other plausible triggering factors such as tectonics, are considered the responsibles
of the tufa “erosion episodes” and the transitions between facies. The successive
dissection episodes generally took place in the spotted area during transition climate
conditions, from the relatively wet early Holocene to the more arid late Holocene. |
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