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1. Dimensions of Radiocarbon Variability within Sedimentary Organic Matter

   https://doi.org/10.1017/RDC.2018.22  

   Bao, Rui; McNichol, Ann P; McIntyre, Cameron P; Xu, Li; Eglinton, Timothy I (June 2018, Radiocarbon)

   ABSTRACT Organic carbon (OC) radiocarbon ( 14 C) signatures in marine surface sediments are highly variable and the causes of this heterogeneity remain ambiguous. Here, we present results from a detailed 14 C-based investigation of an Arabian Sea sediment, including measurements on organic matter (OM) in bulk sediment, specific grain size fractions, and OC decomposition products from ramped-pyrolysis-oxidation (RPO). Our results show that 14 C ages of OM increase with increasing grain size, suggesting that grain size is an important factor controlling the 14 C heterogeneity in marine sediments. Analysis of RPO decomposition products from different grain size fractions reveals an overall increase in age of corresponding thermal fractions from finer to coarser fractions. We suggest that hydrodynamic properties of sediment grains exert the important control on the 14 C age distribution of OM among grain size fractions. We propose a conceptual model to account for this dimensionality in 14 C variability that invokes two predominant modes of OM preservation within different grain size fractions of Arabian Sea sediment: finer (<63 µm) fractions are influenced by OM-mineral grain aggregation processes, giving rise to relatively uniform 14 C ages, whereas OM preserved in coarser (>63 µm) fractions includes materials encapsulated within microfossils and/or entrained fossil ( 14 C-depleted) OC hosted in detrital mineral grains. Our findings highlight the value of RPO for assessment of 14 C age variability in sedimentary OC, and for assessing mechanisms of OM preservation in aquatic sediments. 

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2. Seismic response of Nenana sedimentary basin, central Alaska

   Smith, Kyle; Tape, Carl; Tsai, Victor C. (January 2023, Bulletin of the Seismological Society of America)
3. The Sedimentary Geochemistry and Paleoenvironments Project

   https://doi.org/10.1111/gbi.12462  

   Farrell, Úna C.; Samawi, Rifaat; Anjanappa, Savitha; Klykov, Roman; Adeboye, Oyeleye O.; Agic, Heda; Ahm, Anne‐Sofie C.; Boag, Thomas H.; Bowyer, Fred; Brocks, Jochen J.; et al (July 2021, Geobiology)
4. Site M0077: Post-Impact Sedimentary Rocks

   https://doi.org/10.14379/iodp.proc.364.105.2017  

   Gulick, S; Morgan, J; Mellett, CL; Green, SL; Bralower, T; Chenot, E; Christeson, G; Claeys, P; Cockell, C; Coolen, MJL; et al (December 2017, International Ocean Discovery Program)
5. Deep-Time Marine Sedimentary Element Database

   https://doi.org/10.5194/essd-17-1613-2025  

   Lai, Jiankang; Song, Haijun; Chu, Daoliang; Dal_Corso, Jacopo; Sperling, Erik A; Wu, Yuyang; Liu, Xiaokang; Wei, Lai; Li, Mingtao; Song, Hanchen; et al (January 2025, Earth System Science Data)

   Geochemical data from ancient marine sediments are crucial for studying palaeo-environments, palaeo-climates, and elemental cycles. With increased accessibility to geochemical data, many databases have emerged. However, there remains a need for a more comprehensive database that focuses on deep-time marine sediment records. Here, we introduce the Deep-Time Marine Sedimentary Element Database (DM-SED). The DM-SED has been built upon the Sedimentary Geochemistry and Paleoenvironments Project (SGP) database with a new compilation of 34 874 data entries from 433 studies, totalling 63 627 entries. The DM-SED contains 2 522 255 discrete marine sedimentary data points, including major and trace elements and some stable isotopes. It includes 9207 entries from the Precambrian and 54 420 entries from the Phanerozoic, thus providing significant references for reconstructing deep-time Earth system evolution. The data files described in this paper are available at https://doi.org/10.5281/zenodo.14771859 (Lai et al., 2025). 

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