"Sedimentation patterns on Lanzarote reflecting quaternary environmental changes in the Eastern Canaries and North Africa."

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About 1000 ka ago a volcano dammed the valley of Femes situated in Fuerteventura (Canary Islands). Since then all kind of sediments are stored in the valley. In the center of the valley about 50m of sediments are horizontally deposited consisting of in situ soils, characterized by a considerable smectite content, of soil sediments, of tephra and lapilli material as well as of eolian sediments. Most of the eolianites come from the African continent. They contain quartz (in changing grain sizes) and clay minerals (kaolinite and illite), components that are not existent on the island and cannot be formed on it. We aim to reconstruct the sedimentation history of the valley of Femes, and by means of sediment characteristics deduce triggering causes and controlling factors. Furthermore we aim to work out environmental changes through time by means of ostracode analyses. A multiproxy-approach is used to contribute to the question, if and to what extend supra-regional climate phenomena (Heinrich events or precession caused Monsoon activity) are playing a major role in respect to the sedimentation history and to in situ soil formation. We assume that 1. in situ soil formation (smectite) reflect stable environmental conditions linked to more precipitation on the island.2. Heinrich events could be related to dryer conditions in the northwest Saharan source area and thus favor dust supply with giant quartz grains. 3. changing monsoon activity triggered by precession in sub-Saharan Africa resulted in changing landscape conditions (stable/instable) and thus to changing sediment supply in respect to kaolinite content and silty quartz grains.