engleski

Pleistocene glacial and periglacial sediments of Kvarner, northern Dalmatia and southern Velebit Mts. - evidence of Dinaric glaciation

The research comprised field study of Quaternary sediments on Krk, Rab and Pag Islands, Senjska Draga, Jablanac, South Velebit, the coast of Velebit Channel, and Northern Dalmatia (Novigrad Sea, Karin Sea, Obrovac, Paljuv and Smilčić), detailed logging, outcrop mapping and radiometric dating, and the sedimentological data confirmed glacigenic interpretation of the studied sediments, namelly: Glacial sediments, tills or tillites form ground, medial or lateral moraines, and their main characteristics are clasts with glacial striae, ice-shaped (faceted, bullet-shape and conical) and ice-shattered clasts. Glacifluvial sediments comprise glacial outwash deposits of braided streams and flood plains, and fluvial deposits of meandering rivers. The glacigenic origin is based on their occurrence with tills or tillites, and glacially-derived debris. Glacilacustrine sediments comprise clay-silt sediments with classic varves, and varve-like calcisiltites with drop-stones. Glacideltaic sediments are conglomerates, calcarenites and calcisiltites in alternation. Ice-striated clasts, and their association with glacilacustrine sediments, document their glacigenic origin. The following depositional paleoenvironments were reconstructed: a) glacial environment is documented by ground and lateral moraines. The ground moraines are indentified as Rujno, Paklenica and Novigrad members and two tentative members are Sklopine and Raduč. The Paklenica member, found also on Krk and Rab Islands, documents the furthest extent of glaciation. Another characteristic landform of ice-contact zone are kame terraces well preserved on the Krk and Pag Islands. b) proglacial environment influenced by melting ice and glacial outwash processes is widespread in Northern Dalmatia, and proglacial lacustrine sediments of Ždrilo, Seline and Novigrad. c) periglacial environment, is recognized in sediments of Novigrad section, were ice-wedge casts and kettle-forms occur, which indicate freezing and thawing of sediment. The sedimentological data proved far seawards extention of the Dinaric glaciation which at the most advanced phase reached islands of Krk, Rab and Pag, a large part of Northern Dalmatia, and the whole Velebit Channel. Chronostratigraphic correlation of sediments is based on allostratigraphy and 14C and U-series ages of sediments, which allowed attribution of the Middle Pleistocene age to most of the studied sediments.

Middle Pleistocene; sediments; glacial; periglacial; Dinaric glaciation; Adriatic; Velebit

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