Fig 1.
(a) Croatia and the Adriatic Sea. (b) Zadar archipelago and location of ancient saltpans. (c) Brbinj on Dugi Otok. (Source: ESRI, Maxar, Earthstar geographics, and the GIS User Community) (d) The saltpans area and the location of the cores (Source: digital surface model of the site generated by the authors, based on Bechor et al. [35]). The figures are similar but not identical to the original images and are therefore for illustrative purposes only.
Fig 2.
Schematic sketch of the saltpan’s structures and their relations to sea level.
(a) Schematic drawing of the surveyed saltworks site in Brbinj, the locations of the basins and the examined cores. (b) Present-day relations between MSL and manmade structures.
Table 1.
Main characteristics of the collected cores in Brbinj.
Fig 3.
The lithological units, CT, and grain size, of the cores BRB-1, BRB-2 and BRB-5.
The cores are aligned below the current MSL (BMSL) and presented in correlation with the top of the separation wall, the bottom of the sluice gate, and the derived paleo MSL.
Fig 4.
Foraminiferal and ostracod characteristics of core BRB-2 vs.
current MSL. Abundance (number of shells/10 cm3), species richness (number of species/sample), and dominance (%). Relative foraminiferal abundances of coastal species (Ammobaculites sp., Ammoscalaria runiana, Ammonia aberdoveyensis, Ammonia parkinsoniana, Ammonia pawlowskii, Cribroelphidium poeyanum, Cribroelphidium williamsoni, Elphidium aculeatum, Elphidium advenum, Elphidium crispum, and Elphidium limbatum) vs. euryhaline species (Ammonia veneta) based on Alve and Murray [49], Avnaim-Katav et al. [52], Hayward et al. [53] and Schönfeld et al. [54]. Relative ostracod abundances of coastal species (Xestoleberis communis, Aurila prasina, Aurila woodwardi, Leptocythere lagunae, Loxoconcha cf. elliptica and Loxoconcha ovulata) vs. euryhaline species (Cyprideis torosa f. littoralis) based on Bonaduce [59] and Mazzini et al. [61].
Fig 5.
Foraminifera from core sediments collected in Brbinj, Dugi Otok, Dalmatian coast, Croatia.
(1a–c) Ammonia aberdoveyensis Haynes 1973, (a) Spiral side view, (b) Umbilical side view, (c) Profile view; (2a–c) Ammonia veneta (Schultze 1854), (a) Spiral side view, (b) Umbilical side view, (c) Profile view; (3a–c) Ammonia parkinsoniana (d’Orbigny 1839), (a) Spiral side view, (b) Umbilical side view, (c) Profile view; (4a–c) Ammonia pawlowskii Hayward and Holzmann 2019, (a) Spiral side view, (b) Umbilical side view, (c) Profile view. Note: we used the sutures characteristics and the test profile as morphological features for distinguishing A. aberdoveyensis from the most similar non-ornamented species A. veneta [53, 54]. Sutures on the domed spiral side of A. veneta are flushed, raised and covered by calcite ridges ornament, whereas A. aberdoveyensis is characterized by a weakly convex to flat spiral side with its smoother sutures.
Fig 6.
Ostracod valves from core sediments collected in Brbinj, Dugi Otok, Dalmatian coast, Croatia.
(1) Cyprideis torosa f. littoralis (Jones 1850) left valve (LV); (2–3) Aurila woodwardi (Brady 1868), (2) right valve (RV), (3) LV; (4) Leptocythere lagunae Hartmann 1958 RV; (5) Leptocythere cf. bacescoi (Rome 1942) RV; (6) Leptocythere cf. bituberculata Bonaduce, Ciampo and Masoli 1976 LV; (7) Callistocythere cf. adriatica Masoli 1968 RV; (8) Xestoleberis communis Müller 1894 RV; (9) Loxoconcha rhomboidea (Fischer 1855) LV; (10) Loxoconcha cf. ovulata (Costa 1853) RV; (11) Loxoconcha cf. elliptica Brady 1868 juvenile, LV.
Fig 7.
Foraminiferal and ostracod characteristics of core BRB-5 vs. current MSL.
Subdivision into units used in the text are denoted and explained in the caption of Fig 4.
Fig 8.
Variations in terrigenous elements ratios to Ca in cores BRB-1, BRB-2 and BRB-5.
Elevations are relative to the current MSL.
Fig 9.
Comparison of elements concentrations and their ratios to Ca, between current study samples from the reddish layers in Brbinj (BRB) to terra rossa soil from Zadar area (ZDR), following Halamić et al. [46].
(a) Concentrations of Ca, K, Mg and Ti. (b) Concentrations of Al and Fe. (c) Concentrations of Co, Nb and Pb. (d) Concentrations of Zn, Cr and Ni. (e) Ratios of Mg/Ca, K/Ca, and Ti/Ca. (f) Ratios of Al/Ca and Fe/Ca.
Table 2.
Summary of OSL dating.
Fig 10.
Schematic reconstruction of the saltpans in Brbinj during its operational period.
Past sea-level, based on elevations of the sluice gate bottom and the separation wall top [35]. The paved, euryhaline layers and the RSL lower limiting points, were identified in the current study.
Fig 11.
Reconstruction of RSL in central Dalmatia, during the last two millennia.
Our newly suggested limiting points of RSL at Brbinj and the determined OSL age, in comparison to previously presented reconstructions and inferences of glacio-isostatic prediction models [35, 79].