Perspectives of IODP3 Expedition 506S SIGNALS - Stratigraphic InteGration of North Atlantic Legacy Sites

SPARC (Scientific Projects using Ocean Drilling Archives) is an IODP³ programme to utilize legacy cores by large-scale research groups. Three projects (Exp. 504S, Exp. 505S, Exp. 506S) were launched in the first year, with a start date in summer or fall and will last for three years.

The North Atlantic plays a crucial role in regulating global climate due to its proximity to major ice sheets and sensitivity to changes in the Atlantic Meridional Overturning Circulation (AMOC). Over millennial and orbital timescales, the region has experienced abrupt climate shifts with significant global implications. The Exp. 506S SIGNALS (Stratigraphic InteGration of North Atlantic Legacy Sites) project aims to synthesize and integrate legacy records into a coherent, four-dimensional stratigraphic framework to provide a regional reconstruction of past climate variability on millennial to orbital timescales since the late Miocene.

SIGNALS will enhance stratigraphic correlation, refine age models, and synchronize proxy datasets for multiple legacy sites across the North Atlantic spanning a wide range of climatic and bathymetric gradients. The project will capitalize on advanced methods, including machine learning and signal correlation algorithms, to rapidly produce high-resolution data by automated processing of core images, point counting, and precise stratigraphic correlation.

SIGNALS will address methodological issues associated with estimating uncertainty in stratigraphic correlations and the limits of temporal resolution at each site given varying sedimentation rates, bioturbation, and sampling frequency. Furthermore, we will develop process models to understand how orbitally-driven climatic changes are expressed as cycles in the stratigraphic record of each site. By analyzing high-resolution geochemical and sedimentological proxies in a robust stratigraphic framework, the project seeks to reconstruct climate evolution and ocean circulation changes across the North Atlantic since the late Miocene. The project will focus on major climatic transitions and provide robust regional paleoclimate data for numerical modeling and assimilation studies. Beyond research advancements, SIGNALS will also foster collaboration by developing user-friendly computational tools, training early-career researchers, and making data publicly accessible through open repositories.

Although the exact implementation plan will not be decided until the science team has been selected, we will present objectives and general plans of Exp. 506S SIGNALS as one of the first SPARC projects.