A new _13Ccarb curve from the Green Point section (Newfoundland, Canada), the GSSP of the Cambro-Ordovician Boundary, has been constructed because (1) no high-resolution carbon isotope profile was previously presented for the GSSP section and (2) the exact stratigraphic level of the Cambrian–Ordovician boundary, based on conodont biozonation, has become recently an issue of debate. The previously constructed C-isotope profile was based on lower resolution field sampling protocols. The δ13C values of 84 well-preserved micrite microsamples range from –4.7 ‰ to +1.7‰ (VPDB) and the profile reveals a composite negative shift (three peaks) of ~ 6.0 ‰. The combination of C-isotope stratigraphy with biozonation provides a powerful tool of high-resolution global correlations.
The 13δCcarb curve from the Green Point succession in western Newfoundland, Canada and correlation of the GSSP section of the Cambrian-Ordovician boundary
BAGNOLI, GABRIELLA;
2013-01-01
Abstract
A new _13Ccarb curve from the Green Point section (Newfoundland, Canada), the GSSP of the Cambro-Ordovician Boundary, has been constructed because (1) no high-resolution carbon isotope profile was previously presented for the GSSP section and (2) the exact stratigraphic level of the Cambrian–Ordovician boundary, based on conodont biozonation, has become recently an issue of debate. The previously constructed C-isotope profile was based on lower resolution field sampling protocols. The δ13C values of 84 well-preserved micrite microsamples range from –4.7 ‰ to +1.7‰ (VPDB) and the profile reveals a composite negative shift (three peaks) of ~ 6.0 ‰. The combination of C-isotope stratigraphy with biozonation provides a powerful tool of high-resolution global correlations.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
