THE EXTENDING OCEAN DRILLING PURSUITS (EODP) PROJECT: SPATIAL DISTRIBUTION OF BIOGENIC SEDIMENTS THROUGH THE CENOZOIC

Deep-sea sediments are exceptionally well-preserved in the geological record and provide extensive insights into ocean-atmosphere-biosphere interactions. Quantifying how sedimentation has evolved both temporally and spatially offers a unique perspective of how these interactions impact upon production, deposition, and preservation of sediments across various scales. Biogenic sediments, in particular, are dominantly composed of skeletal material from microorganisms, and are exceptional indicators of marine biogeochemical cycles; especially the carbon and silica cycles. While we are aware that microfossils and the sediments they produce vary across space, this is frequently ignored due to the time required and complex nature of reconstructing paleogeographic information for a robust analysis. Most existing data is centered on specific periods of time or concentrated regions, predominantly near continents and continental shelves, which thus misses key trends of how sedimentation has changed across major transitions.

The abundance, preservation, and distribution of calcareous and siliceous microfossils in sediments are influenced temporally and spatially by several abiotic and biotic factors including temperature, ocean circulation patterns, surface productivity, and bacterial activity. Subsequently, mapping paleo-sedimentation patterns can be utilized as a practical visual resource to understand the nature of marine environments and oceanic response to climate perturbations at the time of deposition. Here, using the vast quantities of scientific ocean drilling data compiled and harmonized in the extending Ocean Drilling Pursuits (eODP) project, initial distributions of four microfossil groups (planktic foraminifera, calcareous nannofossils, radiolarians, and diatoms) and the spatial extent of their corresponding lithologies are analyzed and visualized on a global scale, to infer how and why sedimentation patterns have developed through time and across space.