In the frame of discussion on speleothem sedimento-logy we introduce a particular subclass of speleothemes undergoing accretion both in the continental (subaerial dripstones) and marine (marine organic overgrowth) environments, and describes the chemical-phisycal aspects of speleotheme growth. Hus allows a correct use of this speleothem subclass in paleoclimatic and eustatic investigation. Applications and limits of the most common datation techniques (U/Th,14C) to the chronological reconstructions of sea level oscillations are outlined. The significance of speleothemes wide marine overgrowth as paleoclimatic indicators through the analysis of variations in oxygen and carbon isotopie rations is also discussed (δ;18O e δ13C). The integrations of informations deriving from continental and submerged speleothem allow detailed paleoenvironmental reconscrutions to be made. Durin glacial-interglacial oscillations, an encrease of δ;18O indicate cooling, and marine organogenic overgrowth on speleothemes allows the precise detection of submsion timing.
|Titolo:||Sea level curve and paleoclimatic determination from speleothems [L'uso degli speleotemi per ricostruzioni paleoclimatiche e variazioni del livello del mare]|
|Data di pubblicazione:||1998|
|Appare nelle tipologie:||1.1 Articolo in rivista|