The aim of this paper is to use inorganic geochemical analysis of fine-grained sediments to shed light on the depositional and diagenetic processes related to the development of the Mesozoic–early Cenozoic rifted margin of the northwest Atlantic Ocean off Newfoundland (Canada), as sampled during Leg 210 (Tucholke, Sibuet, Klaus, et al., 2004). Site 1276 is located at the base of the continental rise east of the Grand Banks/Flemish Cap (Figs. F1, F2). Chemical data presented here complement the information from core descriptions, smear slide analysis, X-ray diffraction (XRD), and preliminary chemical analysis, as obtained at sea (Shipboard Scientific Party, 2004). Analysis of chemical changes in fine-grained sediments through time is useful to identify changes in sediment provenance, paleoceanography, and diagenesis. Despite this, published geochemical analyses of deep-sea sediments that cover a long time-range, as presented here, remain remarkably rare.
Fine-grained sediments that were studied represent a combination of background hemipelagic sediments and the fine-grained upper intervals of turbidites, which in many instances cannot be easily distinguished from one another in the cores (Shipboard Scientific Party, 2004). These sediments experienced extensive mixing during sediment transport, prior to final deposition, and are therefore likely to record the composition of a range of source rocks exposed over a wide area in the region of sediment supply. Sand-sized sediment was studied petrographically in a related study (Marsaglia et al., this volume).