Carbon isotope stratigraphy: a tool for basin to carbonate platform correlation

Abstract

ABSTRACT The Early Cretaceous carbonate carbon isotope stratigraphy established in pelagic limestones is marked by several pronounced excursions towards positive δ 13 C values. We investigated a biostratigraphically and palaeomagnetically calibrated Aptian section to see whether C isotope stratigraphy could be recognized in shallow‐water carbonates. The chosen carbonate platform sections are located in southern Italy and have been dated by biostratigraphy. Bulk samples, chosen from the Barremian‐Albian part of the sequence, were analysed for their O and C isotope compositions. The C isotope curve established shows two major positive excursions which can be correlated with the synchronous and globally recognized Aptian C isotope events. The data provide evidence that C isotope stratigraphy can be used as a powerful correlation tool between pelagic and shallow‐water limestone sequences.