HR: 1340h
AN: U13B-1145    [Abstracts]
TI: Millennial-scale Hydrological Fluctuations in Western Mediterranean During the Last 20 ka: The Sedimentary Record of Lake Estanya (NE Spain)
AU: * MORELLON, M
EM: mariomm@ipe.csic.es
AF: Instituto Pirenaico de Ecología (IPE) – CSIC, Campus de Aula Dei. Avenida Montañana 1005, Zaragoza, 50059, Spain
AU: VALERO-GARCÉS, B
EM: blas@ipe.csic.es
AF: Instituto Pirenaico de Ecología (IPE) – CSIC, Campus de Aula Dei. Avenida Montañana 1005, Zaragoza, 50059, Spain
AU: MORENO, A
EM: amoreno@ipe.csic.es
AF: Instituto Pirenaico de Ecología (IPE) – CSIC, Campus de Aula Dei. Avenida Montañana 1005, Zaragoza, 50059, Spain
AU: MORENO, A
EM: amoreno@ipe.csic.es
AF: Limnological Research Center (LRC) - University of Minnesota, 310 Pillsbury Drive SE, Minneapolis, MN 55455, United States
AU: GONZALEZ-SAMPERIZ, P
EM: pgonzal@ipe.csic.es
AF: Instituto Pirenaico de Ecología (IPE) – CSIC, Campus de Aula Dei. Avenida Montañana 1005, Zaragoza, 50059, Spain
AU: RICO, M
EM: mayterico@ipe.csic.es
AF: Instituto Pirenaico de Ecología (IPE) – CSIC, Campus de Aula Dei. Avenida Montañana 1005, Zaragoza, 50059, Spain
AU: CORELLA, J
EM: pablocorella@ipe.csic.es
AF: Instituto Pirenaico de Ecología (IPE) – CSIC, Campus de Aula Dei. Avenida Montañana 1005, Zaragoza, 50059, Spain
AU: MATA, P
EM: pilar.mata@uca.es
AF: Facultad de Ciencias del Mar y Ambientales. Universidad de Cádiz, Avenida República Árabe Saharaui s/n. Polígono Río San Pedro., Puerto Real (Cádiz), 11510, Spain
AU: MARTIN-PUERTAS, C
EM: celia.martin@uca.es
AF: Facultad de Ciencias del Mar y Ambientales. Universidad de Cádiz, Avenida República Árabe Saharaui s/n. Polígono Río San Pedro., Puerto Real (Cádiz), 11510, Spain
AU: ANSELMETTI, F
EM: flavio@erdw.ethz.ch
AF: Geological Institute - ETH Zürich, Sonneggstrasse 5, Zürich, CH-8092, Switzerland
AU: ARIZTEGUI, D
EM: Daniel.Ariztegui@terre.unige.ch
AF: Section des Sciences de la Terre. Faculté des Sciences. Université de Genève, Rue des Maraîchers 13, Geneva, CH-1205, Switzerland
AU: SCHNELMANN, M
AF: Geological Institute - ETH Zürich, Sonneggstrasse 5, Zürich, CH-8092, Switzerland
AB: The impact of North Atlantic changes in Western Mediterranean Sea has been widely documented by marine records (Cacho et al., 2001; Martrat et al., 2004 and 2007; Moreno et al., 2005). Although this teleconnection has also been recorded in several mountain records of northern Spain (Allen et al., 1996; Leira and Santos, 2002; González-Samperiz et al., 2006), the environmental effects and the hydrological amplitude of these fluctuations in continental, low-land areas of Iberian Peninsula are still poorly understood. The multi-proxy study of sediment cores from karstic Lake Estanya (Pre-Pyrenees, NE Spain) provides the first continuous record of the hydrological evolution in this area during the deglaciation. The chronological model, based on 14 AMS radiocarbon dates shows an age of ca. 20,000 calendar years BP for the base of the sequence. Seismic stratigraphy revealed a sedimentary filling up to 15 m thick consisting on three main units identifiable through the lake basin and deposited during the Lateglacial, Early-to-Mid Holocene and Late Holocene, respectively. Sediment analyses have been carried out in cores from the deepest area of the lake. Sedimentary facies have been defined after the integration of sedimentological and mineralogical proxies (X-ray diffraction and SEM), high-resolution analyses of light elements (Al, Si, P, S, K, Ca, Ti, Mn and Fe) by XRF core-scanner and stable isotope analyses of ostracods, carbonate phases and organic matter. Increased run-off and higher lake levels are interpreted from massive, clastic facies while more concentrated waters and shallower conditions were more frequent during deposition of laminated and organogenic gypsum-rich facies. Lateglacial sequence shows fluctuating but shallow lake conditions followed by a large increase in water availability during the Early Holocene and lowered lake levels and arid conditions for the Mid-to-Late Holocene (4.2 – 0.8 ka). Fluctuating but higher lake levels occurred during the last 800 years. Millennial-scale hydrological phases recorded in Lake Estanya are coherent with western Mediterranean reconstructions (Frigola et al., 2007) and central Europe lacustrine records (Magny, 2004), but show similarities with northern African records (Lamb et al., 1995) suggesting a complex interplay of mid-latitude and subtropical dynamics in the climatic evolution of the Iberian Peninsula.
UR: http://www.ipe.csic.es/limnogeologia/principal.htm
DE: 4901 Abrupt/rapid climate change (1605)
DE: 4902 Anthropogenic effects (1803, 4802)
DE: 4914 Continental climate records
DE: 4942 Limnology (0458, 1845, 4239)
SC: Union [U]
MN: 2007 Fall Meeting