Isotopic and Petrographic Evidence as a Proxy in Paleoclimatic Reconstructions from Flowstones in Southern Spain

Document pages: 15 pages

Abstract: Changes in the morphology and mineralogy of speleothems (flowstones)clearly respond to climate-related phenomena, such as drip rate variability andtemperature-modulated cave ventilation. Detailed petrographic observations havebeen coupled with δ18O and δ13C values. Fabrics may show changes related to variations insupersaturation, drip rate or input of detrital particles or organic compounds.Fabrics formed under relatively constant and regular drips (columnar compact,open and elongated) show similar δ18O and δ13C values, which are more negativethan those of micrite and microsparite. The combination of internalmicrostratigraphy studies and isotopic data (δ18O and δ13C) from two flowstonescollected from two caves in the north of Almeria province (SE Spain), suggest aspectrum of environmental conditions ranging from wetter to drier periods. Bothrecords constitute a very useful tool for screening and interpretinghigh-resolution paleoclimate reconstructions.