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Neri Ciaranfi, Bari University (Italy)
Assunta D'Alessandro, Bari University (Italy)
Angela Girone, Bari University (Italy)
Fabrizio Lirer, IAMC-CNR (Italy)
Patrizia Maiorano, Bari University (Italy)
Maria Marino, Bari University (Italy)
Nicola Pelosi, IAMC-CNR (Italy)
Leonardo Sagnotti, INGV Roma (Italy)
Simona Stefanelli, Bari University (Italy)
Mauro Brilli, IGAG-CNR (Italy)
Patrizia Macrì, INGV Roma (Italy)
Antonio Cascella, INGV Pisa (Italy)
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The Montalbano Jonico composite section, cropping out in Southern Italy, consists of about 450 m thick coarsening upward deposits from muddy clays to muddy sands; it has been reconstructed in the field by means of selected stratigraphic sections including nine volcaniclastic horizons and four sapropel layers, peculiar micro and macrobenthic assemblages and calcareous plankton biostratigraphic data. The section belongs to an interval across the small Gephyrocapsa and Pseudoemiliania lacunosa nannofossil zones; the lower most part of the section is not older than the Last Appearance Datum of large Gephyrocapsa and the topmost part of the section is not younger that the Last Occurrence of Gephyrocapsa omega occurring in the Mediterranean region. Additionally, the Globoratalia crassaformis influx, Last Common Occurrence of Reticulofenestra asanoi, and temporary disappearance of G. omega have also been recognized. All these events are astronomically dated according to Astronomical Tuned Neogene Time Scale. A complete high-resolution benthic and planktonic foraminiferal stable oxygen isotope record is available at the Montalbano Jonico section and it is well comparable with the standard Atlantic and Pacific benthic foraminiferal δ18O stacks and with the Mediterranean planktonic record. The correlation of isotope record with the sapropel and calcareous plankton stratigraphy provides the recognition of all Marine Isotope Stages between 15 and 36 thus implying that the Montalbano Jonico section is the only continuous benthic and planktonic δ18O on-land reference in the Mediterranean area for the Mid-Pleistocene transition, between about 600 and 1250 ka. A pilot paleomagnetic study of the section indicated that the sequence is characterized by excellent paleomagnetic properties and a complete paleomagnetic study is presently being carried out in order to precisely locate the position of the magnetic polarity reversals. The combined accurate biostratigraphy and sapropel chronology, tephra stratigraphy and isotope record represent strong chronostratigraphic constraints and point out the global chronostratigraphical value of the Montalbano Jonico section, which represents an ideal candidate for the selection of the GSSP of Ionian Stage (Middle Pleistocene).
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