Search results for " Paleoecologia"

Element variability in the coralline alga Lithophyllum yemenense as archive of past climate in the Gulf of Aden (NW Indian Ocean)

2017

This study presents the first algal thallus (skeleton) archive of Asian monsoon strength and Red Sea influence in the Gulf of Aden. Mg/Ca, Li/Ca, and Ba/Ca were measured in Lithophyllum yemenense from Balhaf (Gulf of Aden) using laser ablation inductively coupled plasma mass spectrometry, and Mg/Ca ratio oscillation was used to reconstruct the chronology (34 y). Oscillations of element rates corresponding to the algal growth between 1974 and 2008 were compared with recorded climate and oceanographic variability. During this period, sea surface temperatures (SST) in Balhaf recorded a warming trend of 0.55 degrees C, corresponding to an increase in Mg and Li content in the algal thallus of 2.…

Investigation of marine and continental layers in a stalactite older than 1 million years (Custonaci, north-western sector of Sicily)

2012

Questo lavoro si basa sul ritrovamento, in una grotta carsica, a 100 metri di quota a Custonaci in provincia di Trapani, di una stalattite di notevole interesse paleo climatico, ricoperta da coralli marini, la cui sezione rivela la presenza di 3 Iatus che denotano una interruzione della deposizione di carbonato continentale presumibilmente in seguito a trasgressioni marine. Il carbonato, datato attraverso la metodologia 230Th/U MC-ICPMS (NeptunePlus), ha fornito una età più antica del limite temporale massimo di applicabilità del metodo ( 600 ka). I coralli, che ricoprono il livello continentale più giovane, analizzati usando il rapporto 87Sr/86Sr, hanno fornito una età di 1.1±0.2 Myrs. Al…

Gli ammonoidi della collezione Gemmellaro. La catalogazione informatizzata come base per la revisione sistematica.

2010

Anthropogenic impact and environmental evolution of the last 55 years of the Gulf of Palermo (Sicily, Italy)

2009

The coralline red alga Lithophyllum kotschyanum f. affine as proxy of climate variability in the Yemen coast, Gulf of Aden (NW Indian Ocean)

2014

Abstract Recent investigations have shown the potential of red coralline algae as paleoclimatic archive. A previously unexplored subfamily of coralline algae, the Lithophylloideae, was investigated from the Gulf of Aden (Balhaf, Yemen). Seasonal changes in Mg/Ca, Li/Ca and Ba/Ca composition of Lithophyllum kotschyanum f. affine were investigated by Laser Ablation-Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS). For the first time in coralline algae, the Li/Ca composition was analyzed and showed a highly significant and positive correlation with Mg/Ca and SST. Monthly algal Mg/Ca and Li/Ca variations indicate a positive correlation with sea surface temperature (SST), and sea surface…

Climatic and environmental changes of the last 10 kyr in the central Mediterranean. A study of a core collected in the Gulf of Termini (Sicily, Italy)

2009

Climatic changes during Late Pliocene and Early Pleistocene at Capo Rossello (Sicily, Italy): response from planktonic foraminifera

2004

WATER MASSES EXCHANGE THROUGH THE STRAIT OF SICILY DURING THE LAST DEGLACIAL PERIOD AND THE HOLOCENE

2022

The main goal of this thesis is to explore the inter-basin connection between the eastern and the western Mediterranean (E- and W-Med, respectively) during the last deglacial and Holocene periods (last 15 kyr). The thesis is based on the study of a sediment core recovered at the west flank of Sicily channel (W-Sicily), strategically located under the current path of the surface Atlantic waters and directly below the present-day hydrographic boundary layer between the Eastern Mediterranean Sourced Water (EMSW) and the Western Mediterranean Deep Water (WMDW). This key location allow to explore past changes in both surface and deep water exchange between the E and the W-Med. In this thesis, a …

Origination and extinction patterns of mammals in three central Western Mediterranean islands from the Late Miocene to Quaternary

2008

Abstract An overview of the population histories of three insular realms (Gargano palaeo-archipelago, Sardinia–Maritime Tuscany palaeo-bioprovince and the Sicilian insular complex) during the Late Miocene and Quaternary are here presented. The complexity of biodiversity changes in the islands is analysed to propose an interpretation of origination and extinction patterns. The study highlighted several important aspects of insular faunas. Evolutionary radiations were found to contribute significantly only to the Gargano faunal diversity, likely because the area was an archipelago at the time. Another interesting result is that large and small mammals do not disperse and become extinct all at…

New Data from Pleistocene deposit of S. Ciro cave

2014

Quaternary fossil sites in Sicily have been known for a long time and all of them have a common story of human predation and manipulation. Hence, we illustrate the first electrical tomography applied to the study of a fossiliferous deposit in a cave in Sicily. The site investigated is the deposit inside the cave of San Ciro-Maredolce, near Palermo. This study aims to answer the following questions: is the geoelectric survey applicable to quaternary deposit of caves? is the deposit still existing or has been completely emptied? Here we show a ERT model (Electrical Resistivy Tomography) of deposit and possible anthropogenic interactions (presence of historic and\or illegal excavations) with t…