Annual Report 2009 of the Bartonian/Priabonian Boundary Stratotype Working Group

Tasks of the Italian scientific community were to search for GSSPs of the Middle-Upper Eocene and Lower-Upper Oligocene Transitions. Investigations on both transitions have been undertaken by a number of researchers from several Italian Universities (i.e. Padua, Ferrara, Florence, Urbino, Milan) and CNR Institutes as well as from some European and USA Universities and Institutions of the “ALANO NET” and by the numerous scientists of the OLIS Working Group coordinated by Rio (University of Padua) and Coccioni (University of Urbino), respectively. During the first half of 2009 the multidisciplinary studies on the Alano di Piave section (Veneto region, NE Italy), the potential candidate for defining the GSSP of the Middle/Upper Eocene, equated to the base of the Priabonian Stage, have been completed. An article, entitled “Integrated bio-magnetostratigraphy of the Alano section (NE Italy): a proposal for defining the Middle-Late Eocene boundary” co-authored by Agnini, Fornaciari, Giusberti, Grandesso, Rio & Stefani (Univ of Padua), Lanci (Univ. of Urbino), Luciani (Univ. of Ferrara), Muttoni (Univ. of Milan), Palike & Spofforth (Univ. of Southampton, UK), have been submitted for publication to the Geological Society of America Bulletin in August 2009; it was already reviewed and the revised version will be returned to the Editor before the end of October. The Alano section consists of ca. 120-130 m of bathyal gray marls interrupted in the lower part by 8 meters-thick package of laminated dark to black marlstones. Intercalated in the section there are prominent marker beds, six of which are crystal tuff layers, whereas the other two bioclastic rudites, useful for regional correlation. The section is easily accessible, crops out continuously, is unaffected by any structural deformation, is rich in calcareous plankton and contains an expanded record of the critical interval for defining the GSSP of the Priabonian. Integrated calcareous plankton quantitative biostratigraphy (nannofossils and foraminifera), and a detailed magnetostratigraphic analysis have been conducted in high resolution especially across the critical intervals for defining the Priabonian Stage. Moreover, the depositional paleodepth of the Alano section was estimated through the study of benthic foraminifera, whereas the detailed oxygen and carbon isotope curve for the entire section is included in another paper, submitted to Paleoceanography also in 2009, by Spofforth and co-authors entitled “Organic Carbon Burial following the Middle Eocene Climatic Optimum (MECO) in the central-western Tethys”

Report by Isabella Premoli Silva, Chairwoman