Sedimentation in the Sea Area of the Poreč Harbour

Krunoslav Škaro (HHI); Danijela Bogner; Zvonko Gržetić (HHI);

Godina: 2011


Proceedings of the Tehth International Conference on the Mediterranean Coastal Enviroment, MEDCOAST 11, E. Özhan (Editor), 25-29 October 2011, Rhodes, Grece, MEDCOAST, Mediterranean Costal Foundation, Dalyan, Muğla, Turkey, vol 2, 895 p.

The sea area of the Poreč harbour is semi-coastal area with the size of 383900m2. In his hinterland there is no surface water streams, but has continual anthropogenic influence from the Neolithic to the present. Due to the late Pleistocene-early Holocene transgression that led to the creation of todays Poreč harbour which probably occurred between 7500 to 6500 years BP, a semi-closed area was formed. Geophysical researches are carried out in October 2003, and sediment sampels were collected. Results of analyses imply Holocen sedimentation during which up to 8 m were deposited and coarsening of the sediments towards to coast. In the deepest layer of the core was deposited red soil (Terra Rossa) with the type of clayey silt sediments. Terra rossa soil is typical for the wider area. Her presence in the deepest layer of sediment may be autochthonous (not eroded) and was created in the ground phase, or the allochthonous that was caused due to erosion of the surrounding land, and then transported and deposited in the marine environment. It is assumed that the clayey silt (Terra Rosa) was found throughout the whole area, although its actual thickness was not determined. In the whole area sandy silt was deposited with variable thickness and above it is silty sand. Silty sand was deposited in the coastal area which is most likely due to input of coarse particles from the mainland, the presence of biogenic components and erosion of the central area due to the action of currents and the increased anthropogenic impact (dredging). The sea level rise led to coarsening of sediment particles.