Search results for " foraminifera"
showing 10 items of 74 documents
The Messian Salinity Crisis and the catastrophic Zanclean flooding of the dessicated Mediterranean: the Red Sea record
2013
Facies stacking and extinctions across the Triassic–Jurassic boundary in a peritidal succession from western Sicily
2017
An uppermost Triassic–lowermost Jurassic carbonate platform succession, which is 430 m thick, in northwestern Sicily is described with the aim to provide new data on the sedimentological and biological variations across the Triassic–Jurassic boundary in peritidal environments. The studied succession belonged to the rimmed carbonate shelf that developed during the upper Triassic along the margins of the Ionian Tethys. The peritidal sediments consist of metre-scale shallowing-upward cycles formed by subtidal, intertidal and supratidal facies. Three main informal units are differentiated along the section on the basis of the variations recorded by the subtidal facies. The lower and middle unit…
Benthic foraminiferal assemblage turnover during intensification of the Northern Hemisphere glaciation in the Piacenzian Punta Piccola section (South…
2012
Abstract We present the results of a high-resolution analysis of the benthic foraminiferal assemblages at the Punta Piccola section (Stratotype for the Piacenzian Stage), which spans the gradual climate transition of the intensification of the Northern Hemisphere glaciation (3.6–2.6 Ma). This study highlighted a major benthic foraminiferal fauna turnover, which started at about 3.05 Ma with LO of Cibicidoides italicus , registered the gradual decline of Stilostomella spp. and culminated at about 2.7–2.75 Ma, when the dominant Siphonina reticulata was replaced by Cibicidoides pachyderma , costate Bulimine, spinose Bulimine, spinose Uvigerine and the Bolivina dilatata group. Four compositiona…
Ten Years of Paleoceanographic Studies at ODP Site 963 (Central Mediterranean Sea)
2014
The geographical location, the shape and the circulation pattern makes the Mediterranean Sea an ideal laboratory to study the interplay between different climatic systems, abrupt climate changes and the response of marine ecosystems. The Ocean Drilling Program Site 963 was drilled in the Northwestern part of the Sicily Channel, the sill that divides the western from the eastern Mediterranean Sea. Numerous papers have been published on Site 963 sediments in the last decade, investigating Mediterranean paleoceanographic themes. Here we offer a synthetic framework of these investigations carried out by sub-centennial resolution. We present the whole sequence of suborbital climatic oscillations…
Reconstruction of the environmental evolution of a Sicilian saltmarsh (Italy)
2013
The present study deals with the reconstruction of the environmental evolution of a Trapani saltmarsh (southwestern Sicily, Italy) by combining different analytical approaches such as metal content evaluation, low-field nuclear magnetic resonance (NMR) relaxometry, and benthic foraminifera identification. A 41 cm core was collected in the sediments of a Trapani saltmarsh (southwestern Sicily, Italy) at a water depth of about 50 cm. Different time intervals were recognized, each characterized by peculiar features that testify different environmental conditions. In particular, the bottom layers of the sediment core (41–28 cm) comprised the lowest amount of mud fraction, only some selected met…
Benthic foraminiferal response to trace element pollution. The case study of the Gulf of Milazzo, NE Sicily (Central Mediterranean Sea).
2013
The response of benthic foraminiferal assemblages to trace element pollution in the marine sediments of the Gulf of Milazzo (north-eastern Sicily) was investigated. Since the 1960s, this coastal area has been a preferred site for the development of two small marinas and a commercial harbour as well as for heavy industry. Forty samples collected in the uppermost 3-4 cm of an undisturbed layer of sediment in the littoral environment were used for this benthic foraminiferal analysis. The enrichment factors (EFs) of selected trace elements (As, Co, Cr, Cu, Mn, Ni, Pb and Zn) were also calculated. Changes both in benthic foraminiferal assemblages and in some trace elements concentrations have pr…
First colonization of the genus Amphistegina and other alien benthic foraminifera in the Pelagian Islands and in the south-eastern Sicily (central Me…
2013
Suborbital climate variability during Marine Isotopic Stage 5 in the central Mediterranean basin: evidence from calcareous plankton record
2006
Abstract New faunal and floral records from Ocean Drilling Project Hole 963A, resolved at ∼80-year spacing, provide evidence of suborbital scale climate variability in the central Mediterranean Sea throughout Marine Isotope Stage (MIS) 5. Cold events in the central Mediterranean Sea, indicated by low abundances of warm species and high abundances of cold species, are also evident in a planktonic foraminifera paleoclimatic curve. They have been linked to NGRIP Greenland ice core “C” events and appear correlative with similar sub-millennial climate fluctuations identified in the North Atlantic region and in the Alboran Basin (Westernmost Mediterranean). Low-resolution benthic and planktonic O…
Evolucion paleoambiental desde el Holoceno temprano hasta la actualidad del marjal de Almenara (Mediterráneo occidental)
2018
The main aim of this study is to characterize the different stages in the palaeoenvironmental evolution of the Almenara marsh, Spain, from the early Holocene to the present day. This marsh is one of the most important in Castellón province. Five cores extracted from the marsh underwent sedimentological analysis, micropalaeontological study (foraminifera, ostracods and gastropods) and 14C dating. The results show that before the maximum transgression of the Mediterranean during the Marine Isotope Stage 1 (5500 cal yr. BP dating in the Almenara marsh), the area was occupied by a brackish marsh (prior to the 8.2 ka event). During the middle Holocene, the regional sea level rise and later stabi…
Surface hydrographic changes at the western flank of the sicily channel associated with the last sapropel
2021
Abstract In the eastern Mediterranean Sea, the early Holocene was characterized by major climatic and oceanographic changes that led to the formation of the last sapropel (S1) between 10.8 and 6.1 kyr cal. BP. These hydrographic changes might have altered the water exchange between the eastern and western Mediterranean sub-basins through the Strait of Sicily, but the existing evidences are inconclusive. In the present study we show new evidence from sediment core NDT-6-2016 located at the western flank of the Sicily channel, a key location to monitor the surface/intermediate water exchange between the two Mediterranean sub-basins. We perform paleo-hydrographic reconstructions based on plank…