Holocene palaeoenvironmental evolution of the Ebro Delta (Western Mediterranean Sea) : evidence for an early construction based on the benthic foraminiferal record
MetadataShow full item record
KeywordEbro Delta; Sedimentary sequences; Benthic foraminifera; Environmental evolution; Mediterranean Sea; Holocene
Major Mediterranean deltas began to develop during a period between 8000 and 6000 yr BP when the rate of fluvial sediment input overtook the declining rate of sea-level rise. However, different authors have argued that the Ebro Delta primarily formed during the Late Middle Ages as a consequence of increased anthropogenic pressure on its river basin and these arguments are supported by the scarcity of previous geological studies and available radiocarbon dates. To reconstruct the environmental evolution of the Ebro Delta during the Holocene, we used micropalaeontological analysis of continuous boreholes drilled in two different locations (Carlet and Sant Jaume) on the central delta plain. Different lithofacies distributions and associated environments of deposition were defined based on diagnostic foraminiferal assemblages and the application of a palaeowater-depth transfer function. The more landward Carlet sequence shows an older and more proximal progradational delta with a sedimentary record composed of inner bay, lagoonal, and beach materials deposited between 7600 yr BP and >2000 yr BP under rising sea-level and highstand conditions. This phase was followed by a series of delta-plain environments reflected in part by the Carlet deposits that formed before 2000 yr BP. The Sant Jaume borehole is located closer to the present coastline and contains a much younger sequence that accumulated in the 3 last 2.0 ka during the development of three different deltaic lobes under highstand sea40 level conditions. The results of the present study reinforce the idea that the Ebro Delta dates to the early Holocene, similar to other large Mediterranean deltas.
Author Posting. © The Author(s), 2015. This is the author's version of the work. It is posted here for personal use, not for redistribution. The definitive version was published in The Holocene 26 (2016): 1438-1456, doi:10.1177/0959683616640048.
Showing items related by title, author, creator and subject.
Evolution of a Holocene delta driven by episodic sediment delivery and coseismic deformation, Puget Sound, Washington, USA Barnhardt, Walter A.; Sherrod, Brian L. (Blackwell, 2006-08-16)Episodic, large-volume pulses of volcaniclastic sediment and coseismic subsidence of the coast have influenced the development of a late Holocene delta at southern Puget Sound. Multibeam bathymetry, ground-penetrating radar ...
Hu, Dengke; Clift, Peter D.; Boning, Philipp; Hannigan, Robyn E.; Hillier, Stephen; Blusztajn, Jerzy S.; Wan, Shiming; Fuller, Dorian Q. (John Wiley & Sons, 2013-07-26)Sediments in the Pearl River delta have the potential to record the weathering response of this river basin to climate change since 9.5 ka, most notably weakening of the Asian monsoon since the Early Holocene (∼8 ka). Cores ...
Ashton, Andrew D.; Giosan, Liviu (American Geophysical Union, 2011-07-07)Wave-influenced deltas, with large-scale arcuate shapes and demarcated beach ridge complexes, often display an asymmetrical form about their river channel. Here, we use a numerical model to demonstrate that the angles from ...