Naslov
Luminescence dating of loess from the island of Susak in the Northern Adriatic Sea and the “Gorjanović loess section” from Vukovar in eastern Croatia

Autori
Wacha, Lara

Vrsta, podvrsta i kategorija rada
Ocjenski radovi, doktorska disertacija

Fakultet
Freie Universität, Berlin, Njemačka

Mjesto
Berlin, Njemačka

Datum
17.05

Godina
2011

Stranica
185

Mentor
Frechen, Manfred ; Durn, Goran

Neposredni voditelj
Durn, Goran

Ključne riječi
loess; geochronology; luminescence dating; Susak; Vukovar

Sažetak
Loess-palaeosol sequences are an excellent high-resolution archive for palaeoenvironmental changes. They hide information about the past climate and climatic changes. To be able to reconstruct the palaeoenvironment it is common practice to investigate these deposits with a multidisciplinary approach. A detailed and reliable geochronology is mandatory to be able to interpret the results of such investigations. The aim of this study was to establish a reliable chronological framework of loess-palaeosol sequences from Croatia. In Croatia two major loess regions can be distinguished, the North Adriatic loess region related to the river Po in North Italy and its tributaries and the Danube loess region in eastern Croatia. From both regions the most representative loess-palaeosol sequences were selected for investigations ; the loess-palaeosol sequence on the island of Susak, where up to 90 m of Quaternary deposits, predominantly loess and loess derivatives were determined, and the “Gorjanović loess section” in Vukovar, which is the matter of scientific interest since the last centuries. These two genetically similar but in many ways different remains of climatic fluctuations during the Pleistocene were selected to be the topic for a detailed multi-proxy research for this PhD. This geochronological framework is the first step in high-resolution investigations which is in progress. The dating was performed using infrared stimulated luminescence (IRSL) dating method, which is the method of choice for dating of Quaternary aeolian deposits, as well as radiocarbon dating. Throughout this PhD several luminescence dating protocols were used ; the multiple aliquot additive (MAAD) dose protocol which is a somewhat old-fashioned protocol was used for polymineral fine grain material separated from the loess from Susak for an easier correlation with older published data in this area ; the single aliquot regenerative (SAR) protocol which is a widely used measuring protocol, with fading tests and fading corrections performed on the measured samples as well, to obtain more reliable dating results. For the “Gorjanović loess section” the post-IR IRSL protocol, which is a modified SAR protocol developed recently for dating of older deposits (Middle Pleistocene) was introduced. This protocol has the advantage that it can overcome the performance of fading tests and fading corrections since in this protocol more stable luminescence signals from feldspars are registered. Using the above mentioned laboratory measuring protocols which were supported by numerous experiments and performance tests good and reliable geochronological frameworks for the sections under study were established. The results from the loess-palaeosol sequences on Susak show us that a very detailed record correlating to OIS5 (and possibly OIS6 or older) is preserved, unique in this region. Furthermore, based on the dating results as well as mineralogical and geochemical investigations the three tephra layers were correlated to South Italian volcanic provinces. The luminescence dating results are supported by the radiocarbon dating as well. The “Gorjanović loess section” is an example of the penultimate glacial- last interglacial – last glacial period (OIS6 – OIS2), as seen from the dating results, and can easily be correlated to similar loess-palaeosol sections in the region. In this thesis a detailed and reliable chronological framework of prominent loess-palaeosol sequences in Croatia is established as well as a milestone for a stratigraphy of Quaternary deposits in Croatia.

Izvorni jezik
Engleski

Znanstvena područja
Geologija

Napomena
Rješenje o priznavanju inozemne visokoškolske kvalifikacije, akademski stupanj doktor prirodnih znanosti, od strane Agencije za znanost i visoko obrazovanje, Zagreb, dana 07.09.2011.

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