Controls and Development of Late Quaternary Periplatform Carbonate Stratigraphy in Walton Basin (Northeastern Nicaragua Rise, Caribbean Sea)

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The late Quaternary sedimentary record in periplatform oozes and muds deposited on the northern Nicaragua Rise results from the interplay of four main controls: (1) input of pelagic carbonates and bank‐derived fine aragonite and magnesian calcite; (2) input of siliciclastic sediments; (3) dispersal and removal of sediments by the Caribbean Current; and (4) partial seafloor dissolution of metastable carbonates. High accumulation rates of the calcite coarse sediment fraction throughout the study area demonstrate that planktonic foraminiferal productivity peaked during interglacial stages. Neritic carbonate productivity also peaked during interglacial stages, when bank and shelf tops along the Nicaragua Rise were submerged within the photic zone. Because the bank and shelf tops remained mostly exposed during glacial stages, the surface area available for the neritic carbonate productivity was drastically reduced to a narrow band along the margins of Pedro Bank and the southern shelf of Jamaica. A large volume of siliciclastic sediments, transported from the coastal area of South America and the eastern and western regions of Jamaica, were deposited during glacial stages within the eastern and western deep extensions of Walton Basin. This finding contrasts with the input pattern of siliciclastic sediments in Walton Basin itself, where the largest input of siliciclastic sediments occurred at each of the interglacial climatic optima, corresponding to intervals of maximum sea level transgression. Finally, cores in water depths exceeding 1100 m display during interglacial stages aragonite accumulation rates systematically lower than rates in cores from water depths shallower than 1100 m. This indicates that some bank‐derived aragonite and magnesian calcite has been partially removed by seafloor dissolution in areas from water depths exceeding 1100 m. Results from this study on the northeastern Nicaragua Rise indicate that not only do offbank transport and water column saturation state influence the late Quaternary record but also that the variable strength of the Caribbean Current and the proximity of sources for siliciclastic sediments have played a major role in the development of the late Quaternary periplatform high resolution stratigraphy.