Seabed and Surface Sediment Map of the Kvarner Region, Adriatic Sea, Croatia (Lithological Map, 1:500,000)

• Main Authors: Mladen Juračić, Čedomir Benac, Ranko Crmarić
• Format: Article
• Language: English
• Published: Croatian Geological Survey 2010-11-01
• Series: Geologia Croatica
• Subjects: Sediment; Recent sedimentation; Holocene; Quaternary; Adriatic Sea
• Online Access: http://www.geologia-croatica.hr/ojs/index.php/GC/article/view/268

<div>A lithological map of recent marine sediments and the seabed of</div><div>the Kvarner region (Adriatic Sea, Croatia) is presented on a scale of</div><div>1:500,000. The map was compiled from existing published and</div><div>unpublished data. This is an area characterised by a number of islands</div><div>located between the Istrian Peninsula and the Vinodol-Velebit coast.</div><div>Water depths in channels between the islands reach up to 125 m,</div><div>compared to depths of 40-50 m in the open waters of the adjacent</div><div>northern Adriatic.</div><div>Over most of the Kvarner area, muddy and sandy sediments cover</div><div>the seafloor. Mud (M) is found on the bottom in Rijeka Bay, the</div><div>northern part of the Kvarner, in Kvarneriæ, and in the Vinodol and</div><div>Velebit channels, whereas over the rest of the Kvarner region seafloor</div><div>sandy mud (sM) prevails, with subordinate occurence of gravelly</div><div>mud (gM). Sandy sediments, i.e. muddy sands (mS) dominate in the</div><div>SW part to the open Adriatic, and west of Rab Island, in the Pag and</div><div>Velebit Channels.</div><div>Previous investigations indicate that the fine grained particles</div><div>that are found in deeper parts of Rijeka Bay, Kvarneriæ, and Vinodol</div><div>Channel are of recent origin, and are deposited at water depths below</div><div>the wave base. Sources of these particles are local permanent and</div><div>temporary streams and the direct input from weathering processes,</div><div>along with input by submarine springs (vrulje) near the coast. The</div><div>large areas of the bottom not covered with sediments, or covered with</div><div>gravelly and sandy sediments are found above the wave base, i.e. in</div><div>the erosional wave zone. Coarse-grained material is lithic and/or biogenic.</div><div>However, due to the very rapid Late glacial-Holocene transgression,</div><div>when sea-level rose more than a hundred metres, coarse sandy</div><div>sediments are found below the recent wave base in the SW part</div><div>towards the open Adriatic, and west of Rab Island, in the Pag and</div><div>Velebit Channels. Therefore the sediment distribution in the Kvarner</div><div>region is only partly in dynamic equilibrium with modern hydrodynamic</div><div>conditions.</div>