 |
| Titel |
Using stable isotopes (δ18O and δD) of gypsum hydration water to unravel the mode of gypsum speleothem formation in semi-arid caves |
| VerfasserIn |
Fernando Gázquez, Jose Maria Calaforra, Nicholas P. Evans, David A. Hodell |
| Konferenz |
EGU General Assembly 2016
|
| Medientyp |
Artikel
|
| Sprache |
en
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250128875
|
| Publikation (Nr.) |
 EGU/EGU2016-8911.pdf |
|
|
|
|
|
| Zusammenfassung |
| Subaerial gypsum speleothems form during the evaporation of calcium-sulfate-rich solutions in caves. The evaporation of infiltration water is the widely accepted mechanism to explain precipitation of gypsum speleothems; i.e., the dissolution of gypsum host-rock (e.g. Messinian marine gypsum) supplies $Ca^{2+}$ and $SO_{4}^{2-}$ ions to cave waters and subsequent evaporation leads to gypsum saturation. However, water condensation actively occurs in caves of semi-arid regions and plays a key role in subaerial cave speleogenesis and recharge of aquifers in low-rainfall environments. To date, water condensation in karstic environments has not been considered as an important factor in gypsum speleothem formation.
We collected speleothem samples from the upper passages of Covadura Cave in the gypsum karst of Sorbas (Almeria, SE Spain). This cave is located in a temperate (annual mean temperature of 19.5$^{o}$C), semi-arid region ( |
|
|
|
|
|
|