SSP4.4Late Cretaceous – Early Paleogene climate dynamics and time scales
|Convener: S. Batenburg | Co-Conveners: S. Voigt , A. S. Gale , T. Westerhold|
In the Late Cretaceous to Early Paleogene (~100-50 Ma) Earth’s climate changed from a maximum Greenhouse (during the mid-Cretaceous) to a moderate Greenhouse world, punctuated by extreme events such as widespread ocean anoxia and hyperthermals. Numerous high resolution paleoclimate records are being generated that provide valuable insights in Earth’s most recent hot-house period. However, a deeper understanding of both gradual and rapid climate change depends on accurate and precise timing.
Astronomical tuning has led to significant refinement of Neogene and Paleogene time scales and is now being extended into the Cretaceous. Improved Ar/Ar and U/Pb dating techniques are very close to offering sufficient age constraints to tie in “floating” tunings to the absolute time scale. Thus, investigation of high-quality and high-resolution sedimentary records, with and integrated approach of geochronology and cyclostratigraphy, are now needed to establish a detailed and reliable time scale for the Late Cretaceous – Early Paleogene interval.
The cyclostratigraphic interpretation of Late Cretaceous - Early Paleogene climatic records is strongly related to our comprehension of paleoclimate and paleoceanography. In order to understand drastic events observed in climate proxy records, we need more insight in both periodic and long term changes and variability. This requires an imperative effort to improve the knowledge of the processes affecting the climate/ocean response to astronomical forcing in key areas of the planet during the Late Cretaceous – Early Paleogene interval.
In this session we want to explore: i) the potential for a refined and accurate time scale of the Late Cretaceous – Early Paleogene based on integrated results from cyclostratigraphy and geochronology, ii) the global climate and ocean evolution during the late Cretaceous – Early Paleogene from high-resolution sedimentary records, iii) the climate/ocean dynamics at work during deposition of the Late Cretaceous Ocean Anoxic Events.