EVOLUTION OF COASTAL DEPOSITIONAL SYSTEMS OF THE KRKA RIVER ESTUARY IN RESPONSE TO THE LATE PLEISTOCENE-HOLOCENE SEA-LEVEL CHANGES

doctoral thesis

• Title (english): RAZVOJ OBALNIH TALOŽNIH OKOLIŠA ESTUARIJA RIJEKE KRKE TIJEKOM KASNOPLEISTOCENSKO-HOLOCENSKIH PROMJENA MORSKE RAZINE
• Author: Natalia Smrkulj
• Mentor: Slobodan Miko (mentor)
• Mentor: George Papatheodorou https://orcid.org/0000-0003-3732-1900 (komentor)
• Committee member: Hana Fajković (predsjednik povjerenstva)
• Committee member: Igor Felja (član povjerenstva)
• Committee member: Ozren Hasan (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Geology); Zagreb
• Defense date and country: 2024-11-26, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Geology
• Universal decimal classification (UDC): 55 - Geology. Meteorology. Hydrology

Abstract

Climate and sea-level changes strongly controlled the evolution of shallow coastal
settings worldwide during the Quaternary Period. The shallow coastal region has been
subjected to repeated alternations between the subaerial and marine conditions. The Krka
River mouth area located in central Dalmatia along the microtidal Eastern Adriatic coast
represents a suitable environmental setting for studying palaeoenvironments and relative
sea-level changes. An evolutionary model of the Krka River coastal depositional system was
reconstructed by combining high-resolution acoustic methods and a multiproxy analysis of
sediment cores. The acoustic methods (bathymetrical and seismic studies) provided insight
into the submerged geomorphology and up to 30 m thick sediment sequences preserved in
the study area. The multiproxy analysis was conducted on six sediment cores and included
physical, sedimentological, geochemical, and micropalaeontological analyses supported by 24
radiocarbon dates (14C) to obtain data on benthic communities, hydrological, and depositional
processes related to sea level and climatic conditions and timing of events. The results
indicated fluvial incision and sediment bypass towards the shelf area during the period of low
sea level (lowstand), whereas during the transgressive phase, the shelf area and subsequently
the River canyon were flooded. A system of calcareous tufa barriers started to form in the
upstream tract of the recent Krka River estuary. The calcareous tufa barrier system, together
with sea-level and climate oscillations, had the main influence on the palaeoenvironmental
development of the area. The Holocene sea-level rise progressively flooded the tufa barriers
with the formation of estuarine conditions during the Late Holocene. Human activity
intensified after 600 cal yr BP.

Abstract (english)

Klimatske promjene te promjene morske razine tijekom kvartara znatno su utjecale
na evoluciju obalnih okoliša. Plitka obalna područja pod utjecajem su stalnih izmjena
kopnenih i marinskih uvjeta. Područje ušća rijeke Krke koje se nalazi u središnjoj Dalmaciji na
Istočnoj jadranskoj obali, predstavlja pogodno područje za istraživanje paleookolišnih
promjena te relativnih promjena morske razine. Primjenom visoko-rezolucijskih akustičnih
metoda te „multiproxy“ analizom sedimentnih jezgri rekonstruiran je evolucijski model
taložnih obalnih okoliša rijeke Krke. Akustične metode (batimetrijska i seizmička istraživanja)
dale su uvid u potopljenu geomorfologiju istraživanog područja te u sedimentnu sekvencu
debljine otprilike 30 m. „Multiproxy“ analiza provedena je na 6 sedimentnih jezgri, a
uključivala je fizičke, sedimentološke, geokemijske i mikropaleontološke analize kako bi se
dobili rezultati o bentičkim zajednicama, hidrološkim i taloženim procesima koji ukazuju na
promjene morske razine te klimatske uvjete. Kronologija jezgri zasnivala se na datiranju 24
uzorka metodom radioaktivnog ugljika (14C). Rezultati su ukazali na riječno usijecanje te
transport sedimenta na područje šelfa tijekom razdoblja niske razine mora, dok tijekom
transgresije dolazi do potapanja šelfnog područja, a uzvodno na području današnjeg estuarija
formirao se sustav sedrenih barijera. Sedrene barijere, u kombinaciji s oscilacijama morske
razine i klime, imale su glavnu ulogu na paleookolišni razvoj područja. Porast morske razine
tijekom holocena uzorkuje potapanje sedrenih barijera te formiranje estuuarijskih uvjeta
tijekom kasnog holocena. U posljednjih 600 godina u estuarijskim sedimentima zabilježena je
pojačana antropogena aktivnost i erozija sliva rijeke Krke.

• Keywords: karst estuary; Krka River; sea-level changes; palaeoenvironmental changes; seismic stratigraphy; Eastern Adriatic Coast; late Pleistocene-Holocene
• Keywords (english): krški estuarij; rijeka Krka; promjene morske razine; paleookolišne promjene; seizmička straigrafija; Istočna jadranska obala; kasni Pleistocen-Holocen
• Language: english
• URN:NBN: urn:nbn:hr:217:311125
• Promotion: 2025
• Project: Number: IP-2019-04-8505; Title: Porijeklo i taloženje sedimenata u vrijeme kasno kvartarnih promjena morske razine: Sustav rijeke Krke i Srednjojadranske kotline; Title: Sediments between source and sink during a late Quaternary eustatic cycle: the Krka River and the Mid Adriatic Deep System; Acronym: QMAD; Leader: Slobodan Miko; Jurisdiction: Croatia; Funder: Hrvatska zaklada za znanost; Funding stream: Research Projects
• Study programme: Title: DOCTORAL STUDY OF GEOLOGY; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti u području prirodnih znanosti (doktor/doktorica znanosti u području prirodnih znanosti)
• Type of resource: Text
• Extent: 287 str. ; 30 cm
• File origin: Born digital
• Access conditions: Open access
• Created on: 2025-01-29 10:29:11