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1 June

The main goal is to introduce some of the technical methods of time series analysis and cyclostratigraphy, with the overall focus to enable interested scientists with little experience in time series analysis to “get their hands dirty” while analysing their own data sets. The course notes make use of example data sets, and provide pointers to additional methods and software to conduct the basic steps of analysis of geological data that appear to show evidence of cyclicity. The short course notes presented here were originally developed as teaching material for advanced undergraduate and postgraduate students at the University of Cambridge and Stockholm University. The original notes were modified and enhanced, and aim to supplement the presentation during the Paleontological Society Short Course 2006.

The Palaeocene/Eocene thermal maximum, ∼55 million years ago, was a brief period of widespread, extreme climatic warming, that was associated with massive atmospheric greenhouse gas input. Although aspects of the resulting environmental changes are well documented at low latitudes, no data were available to quantify simultaneous changes in the Arctic region. Here we identify the Palaeocene/Eocene thermal maximum in a marine sedimentary sequence obtained during the Arctic Coring Expedition. We show that sea surface temperatures near the North Pole increased from ∼18°C to over 23°C during this event. Such warm values imply the absence of ice and thus exclude the influence of ice-albedo feedbacks on this Arctic warming. At the same time, sea level rose while anoxic and euxinic conditions developed in the ocean's bottom waters and photic zone, respectively. Increasing temperature and sea level match expectations based on palaeoclimate model simulations, but the absolute polar temperatures that we derive before, during and after the event are more than 10°C warmer than those model-predicted. This suggests that higher-than-modern greenhouse gas concentrations must have operated in conjunction with other feedback mechanisms-perhaps polar stratospheric clouds or hurricane-induced ocean mixing-to amplify early Palaeogene polar temperatures. © 2006 Nature Publishing Group.

The Palaeocene/Eocene thermal maximum represents a period of rapid, extreme global warming ∼55 million years ago, superimposed on an already warm world. This warming is associated with a severe shoaling of the ocean calcite compensation depth and a >2.5 per mil negative carbon isotope excursion in marine and soil carbonates. Together these observations indicate a massive release of13C-depleted carbon and greenhouse-gas-induced warming. Recently, sediments were recovered from the central Arctic Ocean, providing the first opportunity to evaluate the environmental response at the North Pole at this time. Here we present stable hydrogen and carbon isotope measurements of terrestrial-plant- and aquatic-derived n-alkanes that record changes in hydrology, including surface water salinity and precipitation, and the global carbon cycle. Hydrogen isotope records are interpreted as documenting decreased rainout during moisture transport from lower latitudes and increased moisture delivery to the Arctic at the onset of the Palaeocene/Eocene thermal maximum, consistent with predictions of poleward storm track migrations during global warming. The terrestrial-plant carbon isotope excursion (about -4.5 to -6 per mil) is substantially larger than those of marine carbonates. Previously, this offset was explained by the physiological response of plants to increases in surface humidity. But this mechanism is not an effective explanation in this wet Arctic setting, leading us to hypothesize that the true magnitude of the excursion - and associated carbon input - was greater than originally surmised. Greater carbon release and strong hydrological cycle feedbacks may help explain the maintenance of this unprecedented warmth. © 2006 Nature Publishing Group.

This thesis arises from the fact that changes in the geometry of the Earth-Sun system, due to the gravitational interaction among the planets, cause quasi-cyclic climatic variations that are imprinted in the geological record. A speech-recognition method is adapted to provide an automated procedure to calibrate cyclic geological data to astronomical calculations. Synthetic data are used to test the performance of the new method. The new algorithm is then applied to lithological data. Results show that the method is well suited to objectively match geological data to astronomical calculations of the Earth’s orbit. The calibration of the geological time scale is extended into the late Paleogene. This is achieved by generating a lithological proxy record employing an X-ray fluorescence Core Scanner that non-destructively determines elemental concentrations of calcium and iron on split sediment cores. These data exhibit cyclic variations that are shown to be of astronomical origin, and are then used to calibrate the relative duration of magnetochrons C16 through C18. Advanced time series analysis methods are used to extract the astronomical signal. It is shown that the most recent published astronomical solution is not compatible with geological data from the late Paleogene. This new late Eocene time scale is independently confirmed by measurements of stable isotope ratios of oxygen and carbon, obtained from the same material, providing a high-resolution record of climatic variations over intervals of the late Middle and Late Eocene for the first time. Astronomically calibrated geological data are analysed to extract parameters that are required for the calculation of detailed astronomical models. Very small changes in the precession constant of the Earth are extracted by developing a new interference method. This leads to the extraction of the long-term evolution of the tidal dissipation and dynamical ellipticity parameters of the Earth. Geological

This thesis arises from the fact that changes in the geometry of the Earth-Sun system, due to the gravitational interaction among the planets, cause quasi-cyclic climatic variations that are imprinted in the geological record. A speech-recognition method is adapted to provide an automated procedure to calibrate cyclic geological data to astronomical calculations. Synthetic data are used to test the performance of the new method. The new algorithm is then applied to lithological data. Results show that the method is well suited to objectively match geological data to astronomical calculations of the Earth’s orbit. The calibration of the geological time scale is extended into the late Paleogene. This is achieved by generating a lithological proxy record employing an X-ray fluorescence Core Scanner that non-destructively determines elemental concentrations of calcium and iron on split sediment cores. These data exhibit cyclic variations that are shown to be of astronomical origin, and are then used to calibrate the relative duration of magnetochrons C16 through C18. Advanced time series analysis methods are used to extract the astronomical signal. It is shown that the most recent published astronomical solution is not compatible with geological data from the late Paleogene. This new late Eocene time scale is independently confirmed by measurements of stable isotope ratios of oxygen and carbon, obtained from the same material, providing a high-resolution record of climatic variations over intervals of the late Middle and Late Eocene for the first time. Astronomically calibrated geological data are analysed to extract parameters that are required for the calculation of detailed astronomical models. Very small changes in the precession constant of the Earth are extracted by developing a new interference method. This leads to the extraction of the long-term evolution of the tidal dissipation and dynamical ellipticity parameters of the Earth. Geological