Latest Pleistocene and Holocene chronology of an eventful fluvial history.- The Rio Galera in North-Eastern Andalusia
Final Report Abstract
The Holocene sedimentation dynamics of the Rio Galera show a very eventful history and are characterized by changing sedimentation patterns that in turn indicate strongly changing environmental conditions. These sedimentation rhythms of the Rio Galera are unique and individual, however the environmental information stored in the sediments is of regional and supra-regional importance. We aim a chronological classification of these environmental changes. 1. The sediment body begins to build up from 10,300 cal bp with a finely laminated stratification associated to still water conditions. 2. A stronger fluvial dynamic sets in around 9,500 cal bp and shows up in coarse deposits with temporary river incision. 3. From 8,200 cal bp a more humid phase started, which is accompanied by tufa formation that covered the entire valley bottom (swamp formation) and builds up a sediment body of up to 7m thickness. 4. Around 5,800 cal bp the swamp formation ends and the conditions become increasingly drier. Flood plain sediments are deposited on the tufas. 5. From 4,800 cal bp on, slope deposits were accumulated above the flood loams, which we interpret as a sign of even stronger aridification. After this arid phase the river incises to the bottom of the recent valley under more humid conditions. 6. Around 600 before today a last accumulation phase of flood loam deposits starts, which finally builds up a sediment body up to 6 m thick that we interpret as a signal for drier conditions, which last until today.
