Naslov
Mineralogy of Eocene marls of the Eastern Adriatic Coast: a proxy to climatic optima?

Autori
Tomašić, Nenad ; Maljković, Ana ; BREEMECO team

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
23rd General Meeting of the International Mineralogical Association, IMA 2022 Mineralogy and Space / - Lyon, 2022, 10-10

Skup
23rd International Mineralogical Association General Meeting (IMA22)

Mjesto i datum
Lyon, Francuska, 18.07.2022. - 22.07.2022

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
marl, mineralogy, Eocene, climatic optima

Sažetak
Eocene sediments of the Dinaric Foreland basin were imprinted with fossil evidences, which indicate warming trends reaching their maximum in the Early Eocene Climate Optimum (EECO, ca 49 – 53 Ma), and the Middle Eocene Climate Optimum (MECO, ca 40 Ma) warming episodes. In this study within BREEMECO project (IP-2019—04-5775), marls from Mid Eocene flysch sequences were investigated for their mineralogical properties in order to trace evidences of these warming episodes. The samples were collected on two Eastern Adriatic islands mutually 240 km apart, all together at three locations: Baška beach (SE Island Krk, 5 samples), Podstine bay (3 samples) and Zavrače beach (4 samples)(SW Island Hvar). Mineralogical analysis performed by X-ray powder diffraction shows differences in carbonate content and clay mineral assemblage. Semiquantitative mineral composition was determined using relative-intensity-ratio method (RIR). All analyzed samples contain calcite, quartz and clay mineral assemblage. Dolomite occurs only in the Hvar samples, while plagioclase is more frequent in the Krk samples. Calcite content is more abundant in the Hvar samples (Podstine bay 62-69%, Zavrače 8-15% and 40-53%) than in the Krk samples (17-26%), which are thus more argillaceous. The carbonate content shows various regimes of sedimentation of marl along the continental margin in Mid Eocene. Further critical work is currently deployed focusing to clay mineral assemblage in order to find imprints of thermal optima, and initial clay analysis reveals illite, illite-smectite, chlorite, dioctahedral vermiculite and sparse kaolinite as clay mineral phases present.

Izvorni jezik
Engleski

Znanstvena područja
Geologija

POVEZANOST RADA