Ricostruzione paleoclimatica attraverso l'analisi di uno speleotema nella Sardegna centro-orientale: risultati preliminari

Abstract

This paper, carried out in the framework of a local project 60% «Pleistocene-Holocene palaeoclimate and palaeogeography reconstructions based on marine and continental deposits of Sardinia» (Resp. Prof. Sandro De Muro) and within a series of researches involving several bodies (Archaeological Superintendence of NU/SS, Universities of Parma and Cagliari) and caving associations (Gruppo Speleo Ambientale Sassari, Gruppo Speleo-Archeologico Giovanni Spano of Cagliari, Unione Speleologica Cagliaritana and Gruppo Archeo Speleo Ambientale Urzulei), reports the first results of a palaeo-climate study carried out on a stalagmite sampled in the Su Palu cave, Codula Ilune, Urzulei (Central-East Sardinia). This stalagmite has been subjected to radiometric U/Th dating and stable isotope δ180 and δ 13C analysis. These isotopic data based on 139 samples showed a general increase in stable isotope ratios that would indicate a growth of the concretion in a period of global warming (Upper Pleistocene- Holocene?). The chronological setting by means of U/Th datings, unfortunately, did not allow to define the exact timeframe because of the presence of detrital Thorium. C14 analysis are under way to try to obtain information on the time during which the stalagmite growed