Morska i jezerska sedimentacija u potopljenom u potopljenom kršnom bazenu

doctoral thesis

• Title: Morska i jezerska sedimentacija u potopljenom u potopljenom kršnom bazenu : Taložni sustav Lošinjskoga kanala tijekom kasnog kvartara
• Title (english): Marine and lacustrine sedimentation in a submerged karst basin : The Late Quaternary Lošinj Channel depositional system
• Author: Dea Brunović
• Mentor: Slobodan Miko (mentor)
• Committee member: Mladen Juračić (predsjednik povjerenstva)
• Committee member: Vlasta Ćosović (član povjerenstva)
• Committee member: Ivan Sondi (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Geology); Zagreb
• Defense date and country: 2019-01-28, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Interdisciplinary Natural Sciences; Marine Science
• Universal decimal classification (UDC): 55 - Geology. Meteorology. Hydrology

Abstract

Paleookoliši na prostoru današnjeg Lošinjskoga kanala i otoka Cresa mijenjali su se s promjenama morske razine i klime tijekom kasnog kvartara. Depresije u kršu, prisutne na istraživanom području, omogućile su očuvanje sedimentološkog zapisa paleookolišnih promjena. Stoga se paleookolišna rekonstrukcija temeljila na jezgrama sedimenata. Analizirano je ukupno 8 jezgara sedimenata izbušenih u depresijama u kršu. Geokemijske analize, granulometrijske i mineraloške analize, mjerenje magnetskog susceptibiliteta, te izračun fluksa organskog ugljika omogućili su odredbu okoliša koji su postojali na istraživanom prostoru tijekom kasnog kvartara. Mikropaleontološka analiza zajednice foraminifera, ostrakoda, mekušaca i palinomorfa olakšala je interpretaciju prikupljenih podataka. Kronologija jezgara zasnivala se na datiranju metodom AMS 14C. Rezultati analize jezgara sedimenata upotpunjeni su podacima seizmičke refleksije visoke rezolucije. Dobiveni rezultati su ukazali na izmjenu morskih i jezerskih, odnosno kopnenih faza na istraživanom prostoru od MIS 7 do danas, sukladno s varijacijama morske razine. Osnovni čimbenik koji je utjecao na paleookolišni razvoj istraživanog prostora, uz morsku razinu, je dubina praga istraživanih depresija. Interpretacija paleookoliša zasnivala se na korelaciji s modernim analozima kasno-pleistocenskih i holocenskih paleookoliša, odnosno marinskim jezercima danas razvijenim u ponikvama na otoku Cresu.

Abstract (english)

Sea level and climate changes enabled development of different paleoenvironments during the Late Quaternary in the present-day Lošinj Channel and coastal zone of Cres Island. Karst depressions in the investigated area are exceptional geomorphological features for preservation of thick sediment sequences. Therefore, paleoenvironmental reconstruction was based on the sediment cores. Analysis of 8 sediment cores was conducted using the multi-proxy approach and included determination of geochemical and mineralogical composition, grain-size, magnetic susceptibility measurements and organic carbon flux. Paleontological analysis (foraminifera, ostracods, mollusks, palynomorphs) facilitated the interpretation of obtained sediment core data. Core chronologies were based on 14C dating method. The high-resolution seismic data gave an additional insight into the thick sediment sequences preserved in the investigated depressions. The results indicated the exchange of marine and lacustrine or terrestrial environments since MIS 7, in accordance with the Quaternary sea level changes. The main factor that influenced the paleoenvironmental development of the area, except sea level, was the sill depth. The interpretation of paleoenvironments was based on correlation with the modern analogs of the Late Pleistocene and Holocene paleoenvironments, today present in the coastal zone of Cres Island.

• Keywords: paleookoliši; promjene morske razine; kvartar; sedimenti; seizmičke metode visoke rezolucije; geokemija; foraminifere
• Keywords (english): paleoenvironments; sea level changes; Quaternary; sediments; high-resolution seismic methods; geochemistry; foraminifera
• Language: croatian
• URN:NBN: urn:nbn:hr:217:836080
• Study programme: Title: Interdisciplinary doctoral study in Oceanology; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, područje prirodnih znanosti, polje interdisciplinarne prirodne znanosti (znanost o moru) (doktor/doktorica znanosti, područje prirodnih znanosti, polje interdisciplinarne prirodne znanosti (znanost o moru))
• Type of resource: Text
• Extent: 355 str. ; 30 cm
• File origin: Born digital
• Access conditions: Open access; Embargo expiration date: 2021-01-28
• Created on: 2019-04-09 08:26:32