Abstract | Analizom taložnih okoliša dobivaju se informacije o vrsti sedimenta koji se taloži, mineralnom sastavu, gibanju morske vode te organizmima koji nastanjuju to područje. Cilj ovog rada bio je na temelju sedimentnih jezgri u uvali Funtana i Veštar okarakterizirati taložne okoliše. U uvali Funtana uzete su tri jezgre na tri različite postaje. Na južnoj strani uvale uzeta je postaja Funtana 1 (u blizini potoka), na sredini uvale uzeta je jezgra na postaji Funtana 3 te na sjevernoj strani uvale uzeta je jezgra na postaji Funtana 5. Uzorkovanje je obavljeno u tri sezone odnosno proljeće, ljeto i jesen 2021 godine. U uvali Veštar uzete su jezgre na dvije postaje odnosno na području rasta cvjetnice C. nodosa i na području rasta cvjetnice Z. noltii, također u sve tri sezone. Nakon uzorkovanja napravljene su laboratorijske analize poput granulometrije sedimenta putem koje smo dobili informacije o veličini zrna, sortiranosti te vrsti sedimenta. Mikroskopskom analizom pregledani su svi uzorci te fotografirani kako bi se vidio udio litoklasta i bioklasta te postoje li razlike između postaja u svakoj od uvala te razlike između dvije uvale. Mikroskopska analiza dodatno je potvrđena analizom udjela karbonata i mineraloškim sastavom sedimenta. Granulometrijskom analizom utvrđeno je da se u uvali Funtana uzorci razlikuju ovisno o postaji uzorkovanja. Postaja Funtana 1 (F1) okarakterizirana je kao blago šljunkovito-pjeskoviti mulj u većoj mjeri te u manjoj mjeri blago šljunkoviti mulj. Postaja Funtana 3 (F3) okarakterizirana kao šljunkoviti mulj za uzorak iz listopada na dubini jezgre od 18-20 cm, dok ostali uzorci okarakterizirani kao blago šljunkovito-pjeskoviti mulj. Postaja Funtana 5 (F5) granulometrijski se razlikuje ovisno o sezoni uzorkovanja. Ovisno o sezoni uzorkovanja sedimenti su okarakterizirani kao blago šljunkovito-muljeviti pijesak ili blago šljunkovito-pjeskoviti mulj. U uvali Veštar obje postaje granulometrijski su okarakterizirane kao blago šljunkovito-muljeviti pijesak. Udio karbonata u uvali Funtana povećava se od južne strane uvale (postaja F1) prema sjeverno strani uvale (postaja F5). Prosječni udio karbonata na postaji F1 iznosi 20,32±1,59 %, F3 21,29±3,58 %, F5 60,78±8,12 %. U uvali Veštar nema većih razlika između postaje po pitanju udjela karbonata, razlika iznosi oko 0,52 %. Područje rasta cvjetnice C. nodosa iznosi 83,04±6,53 %, a područje rasta cvjetnice Z. noltii iznosi 83,56±5,21 %. Analizom mineraloškog sastava u uvali Funtana pronađeni su dominantni minerali kvarca za postaju F1, a za postaju F5 minerali kalcita i kvarca. Na temelju dobivenih rezultata u uvali Funtana i Veštar okarakterizirani su taložni okoliši za obje uvale. |
Abstract (english) | By analyzing depositional environments, obtained information about the type of sediment that is deposited, its mineral composition, the movement of seawater, and the organisms inhabiting the area. The aim of this study was to characterize the depositional environments in Funtana and Veštar bays based on sediment cores. In Funtana Bay, three cores were taken from three different stations. On the southern side of the bay, station Funtana 1 was sampled (near a water stream), in the middle of the bay, a core was taken at station Funtana 3, and on the northern side of the bay, a core was taken at station Funtana 5. Sampling was conducted in three seasons: spring, summer, and autumn. In Veštar Bay, cores were taken at two stations, one in the area where the seagrass C. nodosa grows and the other in the area where the seagrass Z. noltii grows, also in all three seasons. After sampling, laboratory analyses were conducted, such as sediment granulometry, which provided information on grain size, sorting, and sediment type. All samples were examined microscopically and photographed to observe the proportion of lithoclasts and bioclasts and to identify differences between stations in each bay and differences between the two bays. The microscopic analysis was further confirmed by analyzing the carbonate content and mineral composition of the sediment. Granulometric analysis determined that in Funtana Bay, the samples differ depending on the sampling station. Station Funtana 1 (F1) was characterized as slightly gravelly-sandy silt to a greater extent and slightly gravelly silt to a lesser extent. Station Funtana 3(F3) was characterized as gravelly silt for the October sample at a core depth of 18-20 cm, while other samples were characterized as slightly gravelly-sandy silt. Station Funtana 5(F5) granulometrically varies depending on the sampling season. Depending on the season, the sediments were characterized as slightly gravelly-muddy sand or slightly gravelly-sandy silt. In Veštar Bay, both stations were granulometrically characterized as slightly gravelly-muddy sand. The carbonate content in Funtana Bay increases from the southern side of the bay (station F1) to the northern side of the bay (station F5). The average carbonate content at station F1 is 20.32±1.59 %, at F3 it is 21.29±3.58 %, and at F5 it is 60.78±8.12 %. In Veštar Bay, there were no significant differences between the stations in terms of carbonate content, with a difference of about 0.52 %. The area where C. nodosa grows had a carbonate content of 83.04±6.53 %, and the area where Z. noltii grows had a carbonate content of 83.56±5.21 %. Mineralogical analysis in Funtana Bay found that quartz is the dominant mineral at station F1, while calcite and quartz are the dominant minerals at station F5. Based on the obtained results, the depositional environments for both Funtana and Veštar bays were characterized. |