Early - Midholocene paleoenvironmental shifts and related seasonalities in Andalusia

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In two by the DFG funded projects we were able to depict the fundamentals about Early- and Midholocene paleoenvironmental conditions by means of fluvial dynamics in West and East-Andalusia. This project is based on knowledge obtained from archives of the rivers Guadalete (downstream section) and Galera. We concentrate on a timespan (9 – 5 ka) and investigated soil formation and alluvial deposits in the downstream section of the Rio Guadalete that reached a thickness of 4.5 meters (Wolf et al. 2013; Profile La Ina 3), and tufa formation in the middle course of the Rio Galera that reached up to 5 m in order to obtain a high resolution alluvial history. The tufas at the Rio Galera were fed by rainwater (s. tufa models after PEDLEY 2009) and are qualified for isotope analyses and for further geochemical investigations. The challenge of this project is to test the combination of two methodological approaches. On the one hand we aim to better work out paleoenvironmental shifts by means of fluvial archive study (molluscs and tufas) for the concerned time span. On the other hand we aim to work out environmental seasonality patterns by means of stable isotope analysis (δ13C and δ18O) based on a sclerochronological approach. Therefor we use snail shells from adult species and from well-dated layers. With these sclerochronological data we may be able to depict interannual information on temperature and precipitation that will complete our picture of past environmental and climate variability. We think to combine these two approaches will substantially contribute to a high-resolution research of our sedimentological archives and hence prepare the ground for a profound interpretation.