Phosphorous Diagenesis and Burial in Marine Sediments

磷是海洋生物生产的必需营养素。 海洋沉积物中磷的成岩作用和埋藏效率对海洋生物地球化学循环具有重要控制作用。 在整个地质时期，海洋中磷的含量在很大程度上将受到其在海洋沉积物中的埋藏率的控制。 这对于开发现实的、预测的生物地球化学模型以及沉积记录的解释至关重要。 使用新的选择性顺序提取 (SEDEX) 技术生成的详细固相 p 数据将针对各种典型海洋环境和一个河流-河口-三角洲系统（密西西比河）进行收集。 通过结合孔隙水和其他固相数据检查沉积物中固相磷随深度的重新分布，可以确定海洋沉积物保留磷的相。 这种方法提供了对负责这些相的形成和保存的早期成岩化学反应的深入了解。 成岩模型将用于测试基于固相和孔隙水数据的解释，并就所推断的化学过程的速率得出进一步的结论。 比较沉积物-水界面附近的细尺度（mm）深度区间内固相磷与孔隙水梯度的数量和化学性质，将允许对该界面附近的磷循环和埋藏效率进行量化和表征。 通过比较密西西比河/河口悬浮物中的固相磷形态与相关三角洲沉积物中的固相磷形态，可以量化颗粒磷在穿越特定大陆-海洋界面期间的生物地球化学处理程度。 将产生对磷埋藏的沉积环境控制，从中构建全球海洋磷预算。

Phosphorus is an essential nutrient for biological production in the ocean. Diagenetic processing and burial efficiency of P in marine sediments exert a major control on marine biogeochemical cycles. Over geologic time, the level of P in the ocean will be controlled to a large extent by its rate of burial in marine sediments. This is crucial to the development of realistic, predictive, biogeochemical models and to the interpretation of the sedimentary record. Detailed solid-phase p data, generated using a new selective sequential extraction (SEDEX) technique, will be collected for a diverse suite of typical marine environments and one river-estuary-delta system (the Mississippi). Phase s responsible for P retention by marine sediments will be identified by examining solid-phase P redistribution with depth in sediments in conjunction with pore water and other solid-phase data. This approach provides insight into the early diagenetic chemical reactions responsible for formation and preservation of these phases. Diagenetic modeling will be used to test interpretations made on the basis of solid-phase and pore water data and to draw further conclusions as to rates of the chemical processes inferred. Comparison of the quantity and chemical nature of solid-phase P to pore water gradients over fine-scale (mm) depth intervals near the sediment-water interface will permit quantification and characterization of P cycling and burial efficiency near this interface. The extent of biogeochemical processing of particulate P during transit across a particular continent-ocean interface will be quantified by comparing solid-phase P speciation in Mississippi River/Estuary suspended matter with that in associated deltaic sediments. Depositional environmental controls on P burial will be generated from which to construct a global marine P budget.