Interactions between organic and detrital mineral phases strongly influence both the dispersal and accumulation of terrestrial organic carbon (OC) in continental margin sediments. Yet the complex interplay among biological, chemical, and physical processes limits our understanding of how organo-mineral interactions evolve during sediment transfer and burial. In particular, diverse OC sources and complex hydrodynamic processes hinder the assessment of how the partnership of organic matter and its mineral host evolves during supply and dispersal over continental margins. In this study, we integrate new and compiled sedimentological (grain size, surface area), organic (%OC, OC-δ¹³C, OC-F¹⁴C), and inorganic isotopic (ε_Nd, ⁸⁷Sr/⁸⁶Sr) geochemical data for a broad suite of surface sediments spanning the Western Arctic Ocean from the Bering Sea to the Mackenzie River Delta that capture diverse sources and ages of both terrestrial and marine material deposited in contrasting shelf and slope settings. Spatial gradients in sediment properties were used to delineate regional sources and transport processes influencing the dispersion and persistence of OC-mineral particle associations during export and burial. We found strong relationships between physical parameters, aluminum content, and OC-¹⁴C suggesting that terrestrial OC remains tightly associated with its detrital mineral carrier during source-to-sink transport. Notably, carbon and neodymium isotopic data yield consistent information regarding organic matter provenance. Results obtained highlight the potential for coupled organic-inorganic tracer measurements to elucidate sediment sources and to constrain physical and geochemical processes during sediment mobilization and transport in the Western Arctic Ocean. Tandem measurements of carbon and Nd isotopes may provide a new way to identify large-scale biogeochemical and ecological changes in the sources, nature, and fate of OC stemming from predicted increases in sea ice loss and fluvial inputs of dissolved and particulate OC to this complex and dynamic high latitude marginal sea.

有机相和碎屑矿物相之间的相互作用强烈影响陆缘沉积物中陆地有机碳 (OC) 的扩散和积累。然而，生物、化学和物理过程之间复杂的相互作用限制了我们对沉积物迁移和掩埋过程中有机矿物相互作用如何演变的理解。特别是，不同的 OC 来源和复杂的水动力过程阻碍了对有机物质及其矿物宿主在大陆边缘供应和扩散过程中的伙伴关系如何演变的评估。在这项研究中，我们整合了新的和编译的沉积学（粒度、表面积）、有机（%OC、OC-δ ¹³ C、OC-F ¹⁴ C）和无机同位素（ε _Nd、⁸⁷ Sr/⁸⁶ Sr) 涵盖从白令海到麦肯齐河三角洲的一系列广泛表层沉积物的地球化学数据，这些数据捕获了沉积在对比鲜明的陆架和斜坡环境中的陆地和海洋物质的不同来源和年龄。沉积物特性的空间梯度被用来描绘影响输出和埋藏过程中 OC-矿物颗粒组合的分散和持久性的区域来源和运输过程。我们发现物理参数、铝含量和 OC- ¹⁴之间存在密切关系C 表明在源到汇的运输过程中，陆地 OC 仍然与其碎屑矿物载体紧密相关。值得注意的是，碳和钕同位素数据产生了关于有机物来源的一致信息。获得的结果突出了耦合有机-无机示踪剂测量在阐明沉积物来源和限制西北冰洋沉积物流动和运输过程中物理和地球化学过程的潜力。碳和 Nd 同位素的串联测量可能提供一种新的方法来识别 OC 的来源、性质和归宿的大规模生物地球化学和生态变化，这些变化源于预测的海冰损失增加以及溶解和颗粒 OC 对该复合体的河流输入和动态的高纬度边缘海。