The area of Strunjan cliff is built by Eocene flysch. The facies association is rather monotonous, it's about changing marls and distal siliciclastic turbidites, with intermediate rare, but outstanding calciturbite layers. Between cape Ronek and Sveti Križ we logged 216 meters long sedimentological section. From the whole sequence because of lighter color stands out 8 thicker layers of carbonate turbidites, which I researched detaily for my diploma thesis.
The most representative is 145 cm thick layer, where complete Bouma sequence is visible, where the upper 60 cm represents upper (Te) part of sequence. The thickest 5,7 meters calciturbidite layer is at Sveti Križ. The special feature of this layes is large marly plasticlasts, which are mostly washed out on the surface, so the rock has a hollow appearance. This layer ends with a nearly 3 meters thick limestone marl cap. Other calciturbidite layers are thinner and formed by upper parts of Bouma sequence. Coarse-grained calciturbidites are rudstone to packstone type and are composed of benthic foraminifera, red algae and echinoderm fragments, rarely found are bivalve shells and bryozoans. Limestone clasts, containing biogenic debris, ostracods, planctonic foraminifera and some red algae also appear. They often indicate plastic deformations, so they are most likely eroded outer platform (ramp) or slope sediments. In fine-grained calcarenites we observe plankton foraminifera and quartz grains. Elongated grains are orientatied parallel to the bedding, matrix is micrite with a lot of biogenic debris.
Source area of calciturbidites was Dinaric (Adriatic) Carbonate Platform, flysch on Strunjan cliff does not contain eroded clasts of older platform limestones, which suggests mostly unfurrowed transition between the south lying Dinaric Carbonate Platform and the flysch basin.
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