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Lower Jurassic sedimentary successions in many central and northern Atlantic basins include relatively thick organic-rich intervals. Despite intense research, it is still unclear which mechanisms led to the deposition of these sediments during the Early Jurassic. In this talk, we will (1) present a detailed temporal and geographical framework of Sinemurian and Toarcian organic matter preservation intervals (OMPIs; subdivided into local, regional, and superregional) and (2) broadly constrain the relationship of OMPIs with the Early Jurassic δ13C record. For this, we combine an in-depth analysis of the distribution of organic-rich facies in the Sinemurian and Toarcian with new geochemical data [total organic carbon (TOC) and organic matter pyrolysis] from Portugal, Spain, and Morocco. The developed OMPI framework suggests a strong local control on organic matter preservation during most of the Sinemurian. Regionally widespread organic-rich facies are associated with the most negative δ13C values of the broad Sinemurian-Pliensbachian negative carbon isotopic trend (including the Sinemurian-Pliensbachian Boundary Event). Pliensbachian OMPIs are expressive in the areas bordering the proto-Atlantic Ocean and are often linked with positive δ13C excursions and short-lived warm intervals, but OMPIs are also observed for the Late Pliensbachian cool interval. Toarcian maximum TOC content occurs with the positive 513C (recovery) trend following the 513C negative shift typically linked to the Early Toarcian Oceanic Anoxic Event (T-OAE). However, superregional OMPIs predate and postdate the T-OAE, indicating that conditions favouring the preservation of organic matter (increased productivity and/or enhanced preservation) were not restricted to the T-OAE interval. We will also briefly discuss how future research should aim to disentangle (1) the complexities in estimating original TOC and organic carbon accumulation rates, (2) temporal and spatial variability in environmental or Earth system feedback mechanisms driving sedimentary carbon sequestration, and (3) their combined impact on the global carbon cycle. [ABSTRACT FROM AUTHOR]