RELATIVE SEA-LEVEL CHANGE AND CARBON ISOTOPES - DATA FROM THE UPPER JURASSIC (OXFORDIAN) OF CENTRAL AND SOUTHERN EUROPE

Studies on Cretaceous pelagic Limestones have shown a close correspond ence between putative sea-level curves and the carbon-isotope profile, suggesting a possible relationship between the two phenomena. Such a relationship could relate to shelf-sea area governing the global buria l rate of organic carbon which, in turn, controls the C-13/C-12 ratio of dissolved inorganic carbon in the oceanic reservoir. In order to se e whether or not this relationship might be of more general applicabil ity, the major mid-Oxfordian (Jurassic) transgression is documented to zonal level and appropriate carbon-isotope data are presented. Althou gh the applicability of ammonite zonation to the mid Oxfordian is prob lematic on a regional scale, a clear delta(13)C excursion is present i n the transversarium Zone, which is coincident with regional overstep and/or evidence of shoreline retreat and/or evidence of bathymetric de epening in Europe and elsewhere. The use of the carbon-isotope curve a s a proxy for shelf-sea area or relative sea level is worthy of furthe r exploration.