Astronomic calibration of the late Eocene/early Oligocene Massignano section (central Italy)

We present an astronomically tuned polarity timescale for the late Eocene/early Oligocene based on a
cyclic limestone/marls sedimentary succession exposed at Massignano, Italy (GSSP for the Eocene-
Oligocene boundary). Here we applied spectral analysis techniques to the high-resolution magnetic
susceptibility record. The results provide clear evidence of a regular and cyclic signal that allows us to
discard a stochastic mechanism as controlling these fluctuations. Conversely, these outcomes reveal the
presence of stable and notable periodicities that are in tune with those associated with orbital forcing.
Through a cyclostratigraphic analysis of the rhythmic sedimentary alternations and combination with the
results of time series analysis of the proxy record, we refine the late Eocene portion of the GPTS. Through
astronomical tuning of the rhythmic sedimentary alternations to recent astronomically calculated variations
of Earth’s orbit we recalibrated the polarity boundaries ages and the main stratigraphic events recognized
throughout the sedimentary record. Among these, an age of 33.714 Ma is proposed for the E/O boundary.

Berggren, W. A., D. V. Kent, C. C. Swisher III, and M. P.
Aubry (1995), A revised Cenozoic geochronology and
chronostratigraphy, in Geochronology, Time Scales and Global
Stratigraphic Correlation, edited by W. A. Berggren et
al., Spec. Publ. SEPM Soc. Sediment. Geol., vol. 54,
pp. 129–212.
Bice, D., and A. Montanari (1988), Magnetic stratigraphy of
the Massignano section across the Eocene/Oligocene boundary,
in The Eocene/Oligocene Boundary in the Marche-
Umbria Basin (Italy), Int. Subcomm. on Paleogene Stratigr.,
special publication, edited by I. Premoli Silva, R. Coccioni,
and A. Montanari, pp. 111–117, Ind. Grafiche Fratelli Aniballi,
Ancona, Italy.
Bodiselitsch, B., A. Montanari, C. Koeberl, and R. Coccioni
(2004), Delayed climate cooling in the late Eocene caused by
multiple impacts; high-resolution geochemical studies at
Massignano, Italy, Earth Planet. Sci. Lett., 223(3 –4),
283–302.
Cande, S. C., and D. V. Kent (1995), Revised calibration of the
geomagnetic polarity time scale for the Late Cretaceous and
Cenozoic, J. Geophys. Res., 100, 6093–6095.
Coccioni, R., D. Basso, H. Brinkhuis, S. Galeotti, S. Gardin,
S. Monechi, and S. Spezzaferri (2000), Marine biotic signal
across a late Eocene impact layer at Massignano, Italy: Evidence
for long-term environmental perturbations?, Terra
Nova, 12, 258–263.
Coxall, H. K., P. A. Wilson, H. Pa¨like, C. H. Lear, and
J. Backman (2005), Rapid stepwise onset of Antarctic glaciation
and deeper calcite compensation in the Pacific Ocean,
Nature, 433, 53–57, doi:10.1038/nature03135.
Dell’Antonia, B., A. Bossio, and C. Guernet (2002), The Eocene/
Oligocene and the psycrospheric event in the Tethys as
recorded by deep-sea ostracods from the Massignano Global
Boundary Stratotype Section and Point, central Italy, Mar.
Micropaleontol., 910, 1–16.
Ghil, M., et al. (2002), Advanced spectral methods for climatic
time series, Rev. Geophys., 40(1), 1003, doi:10.1029/
2000RG000092.
Jovane, L., F. Florindo, and J. Dinare`s-Turell (2004), Environmental
magnetic record of paleoclimate change from the
Eocene-Oligocene stratotype section, Massignano, Italy,
Geophys. Res. Lett., 31, L15601, doi:10.1029/
2004GL020554.
Lanci, L., W. Lowrie, and A. Montanari (1996), Magnetostratigraphy
of the Eocene/Oligocene boundary in a short drillcore,
Earth Planet. Sci. Lett., 143, 37–48.
Laskar, J. (1999), The limits of Earth orbital calculations for
geological time-scale use, Philos. Trans. R. Soc. Math. Phys.
Eng. Sci., 357(1757), 1735–1759.
Laskar, J., P. Robutel, F. Joutel, M. Gastineau, A. Correia, and
B. Levrard (2004), A long term numerical solution for the
insolation quantities of the Earth, Astron. Astrophys., 428,
261–285.
Lourens, L. J., and F. J. Hilgen (1997), Long periodic variations
in the Earth’s obliquity and their relation to third-order
eustatic cycles and Late Neogene glaciations, Quat. Int., 40,
43–52, doi:10.1016/S1040-6182(96)00060-2.
Lowrie, W., and L. Lanci (1994), Magnetostratigraphy of Eocene/
Oligocene boundary sections in Italy: No evidence for
short subchrons within chrons 12R and 13R, Earth Planet.
Sci. Lett., 126, 247–258.
Monechi, S., A. Buccianti, and S. Gardin (2000), Biotic signals
from nannoflora across the iridium anomaly in the upper
Eocene of the Massignano section: Evidence from statistical
analysis, Mar. Micropaleontol., 39, 219–237.
Montanari, A., A. L. Deino, R. E. Drake, B. D. Turrin, D. J. De
Paolo, G. S. Odin, G. H. Curtis, W. Alvarez, and D. M. Bice
(1988), Radioisotopic dating of the Eocene-Oligocene
boundary in the pelagic sequence of the northeastern apennineds,
in The Eocene/Oligocene Boundary in the Marche-
Umbria Basin (Italy), Int. Subcomm. on Paleogene Stratigr.,
special publication, edited by I. Premoli Silva, R. Coccioni,
and A. Montanari, pp. 195–208, Ind. Grafiche Fratelli Aniballi,
Ancona, Italy.
Montanari, A., F. Asaro, H. V. Michel, and J. P. Kennett
(1993), Iridium anomalies of late Eocene age at Massignano
(Italy), and ODP 689B (Maud Rise, Antarctic), Palaios, 8,
420–437.
Paillard, D., L. Labeyrie, and P. Yiou (1996), Macintosh program
performs time-series analysis, Eos Trans. AGU, 77,
379.
Pa¨like, H., N. J. Shackleton, and U. Ro¨hl (2001), Astronomical
forcing in late Eocene marine sediments, Earth Planet. Sci.
Lett., 193, 589–602.
Pa¨like, H., J. Laskar, and N. J. Shackleton (2004), Geologic
constraints on the chaotic diffusion of the solar system, Geology,
32(11), 929–932, doi:10.1130/G20750.
Premoli Silva, I., and D. G. Jenkins (1993), Decision on the
Eocene-Oligocene boundary stratotype, Episodes, 16, 379–
382.
Sagnotti, L., F. Florindo, K. L. Verosub, G. S.Wilson, and A. P.
Roberts (1998), Environmental magnetic record of Antarctic
palaeoclimate from Eocene-Oligocene glaciomarine sediments,
Victoria Land margin, Geophys. J. Int., 134, 653–662.
Shackleton, N. J., S. J. Crowhurst, G. Weedon, and L. Laskar
(1999), Astronomical calibration of Oligocene-Miocene time,
Philos. Trans. R. Soc. London, Ser. A, 357, 1909–1927.
Spezzaferri, S., D. Basso, and R. Coccioni (2002), Late Eocene
planktonic foraminiferal response to an extraterrestrial impact
at Massignano GSSP (northeastern Apennines, Italy),
J. Foraminiferal Res., 32, 188–199.
Torrence, C., and G. P. Compo (1998), A practical guide to
wavelet analysis, Bull. Am. Meteorol. Soc., 79, 61–78.
Turco, E., F. J. Hilgen, L. J. Lourens, N. J. Shackleton, andW. J.
Zachariasse (2001), Punctuated evolution of global climate
cooling during the late middle to early late Miocene; highresolution
planktonic foraminiferal and oxygen isotope records
from the Mediterranean, Paleoceanography, 16(4),
405–423.
Vonhof, H. B., J. Smit, H. Brinkhuis, A. Montanari, and A. J.
Nederbragt (2000), Global cooling accelerated by early late
Eocene impacts?, Geology, 28, 687–690.
Wade, B. S., and H. Pa¨like (2004), Oligocene climate dynamics,
Paleoceanography, 19, PA4019, doi:10.1029/
2004PA001042.
Weedon, G. P. (2003), Time-Series Analysis and Cyclostratigraphy,
259 pp., Cambridge Univ. Press, New York.