La Costa del Maresme: cambios recientes en el balance sedimentario
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[1] Universitat de Barcelona
Universitat de Barcelona
Barcelona, España
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[2] Universitat Autònoma de Barcelona
Universitat Autònoma de Barcelona
Barcelona, España
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- Localización: Geotemas (Madrid), ISSN 1576-5172, Nº. 6, 2, 2004 (Ejemplar dedicado a: IV Congreso Geológico de España), págs. 265-267
- Idioma: español
- Enlaces
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Resumen
The Maresme coast Sedimentary Cell extends 60 km southwards from Tordera Delta to Barcelona.
The coast was nourished till few decadas ago with coarse sand from Tordera river. Tordera sediment comes from the erosion and drainage of the granitic Catalan Coastal Range System. Sediment input to the coastal system was up to 200.000 m3/y but presently is less than 50.000 m3/y. The fluvial regime is pluvio-torrential type, with two or three annual avenues. Only higher avenues and dominant drift to the SW nourished delta front system and Maresme sedimentary cell. Continuous presence of siliciclastic coarse sands along this coast result on high reflective beaches. Some relict sedimentary sand bodies are present on its narrow continental shelf described previously as transgressive sand bodies. Present Tordera delta had build up from the maximum transgressive sea level;
previous morphology exerted the control on delta system evolution during latest Pleistocene - Holocene sea-level rise from the lowstand level (Blanes Canyon head at -110 m) to present. At least two intermediate relict delta lobes are present and described for the first time. Modern delta system have just over-pass previous relict lobes and increased its base level up to - 60 m at the same time a sand spit has developed from its mouth to the south, feeded with the main volume of sediment carried out. Maresme cell sedimentary balance is now broken resulting in a general erosive tendency attributed until now to human activity. Described changes on the feeding sediment system can help new practices and policies on ICZM.
