The Pignola-Abriola section (Southern Apennines, Italy) fulfills all the qualifications required by the Subcommission on Triassic Stratigraphy to be proposed as Global Boundary Stratotype Section and Point (GSSP) candidate for the Norian/Rhaetian Boundary (NRB). The Pignola-Abriola section consists of pelagic basinal strata, well exposed and very well preserved with minimal tectonic stress and deformation, outcropping along the SP5 “della Sellata” road in a very accessible location in a protected natural Park, which assures a long-time preservation of the site. The main marker event proposed to define the NRB is the First Appearance Datum (FAD) of the conodont Misikella posthernsteini s.s. at level PIG 24 (m 44.9), which in the study section is associated to other events, useful proxies for the identification of the base of the Rhaetian: 1) the base of the radiolarian Proparvicingula moniliformis Zone; 2) a strong negative shift of the δ13Corg, which is documented as a global marker. Both the δ13Corg negative shift and the FAD of M. posthernsteini s.s. occur within the magnetozone MPA-5r of Pignola-Abriola at ~205.7 Ma. In this work we discuss M. posthernsteini taxonomy, phylogenesis, and global correlations with other fossil groups and physical events. Furthermore, we update the already existing conodont and radiolarian biostratigraphy with new data, providing better constraint of the age interval determined by the conodont species.
The Norian/Rhaetian boundary interval at Pignola-Abriola section (Southern Apennines, Italy) as a GSSP candidate for the Rhaetian Stage: an update
BERTINELLI, Angela;CASACCI, MANUELA;
2016
Abstract
The Pignola-Abriola section (Southern Apennines, Italy) fulfills all the qualifications required by the Subcommission on Triassic Stratigraphy to be proposed as Global Boundary Stratotype Section and Point (GSSP) candidate for the Norian/Rhaetian Boundary (NRB). The Pignola-Abriola section consists of pelagic basinal strata, well exposed and very well preserved with minimal tectonic stress and deformation, outcropping along the SP5 “della Sellata” road in a very accessible location in a protected natural Park, which assures a long-time preservation of the site. The main marker event proposed to define the NRB is the First Appearance Datum (FAD) of the conodont Misikella posthernsteini s.s. at level PIG 24 (m 44.9), which in the study section is associated to other events, useful proxies for the identification of the base of the Rhaetian: 1) the base of the radiolarian Proparvicingula moniliformis Zone; 2) a strong negative shift of the δ13Corg, which is documented as a global marker. Both the δ13Corg negative shift and the FAD of M. posthernsteini s.s. occur within the magnetozone MPA-5r of Pignola-Abriola at ~205.7 Ma. In this work we discuss M. posthernsteini taxonomy, phylogenesis, and global correlations with other fossil groups and physical events. Furthermore, we update the already existing conodont and radiolarian biostratigraphy with new data, providing better constraint of the age interval determined by the conodont species.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
