Eocene biogenic silica accumulation rates at the Pacific equatorial divergence zone
نویسندگان
چکیده
منابع مشابه
Enrichment of dissolved silica in the deep equatorial Pacific during the Eocene-Oligocene
Silicon isotope ratios (expressed as δSi) in marine microfossils can provide insights into silica cycling over geologic time. Here we used δSi of sponge spicules and radiolarian tests from the Paleogene Equatorial Transect (Ocean Drilling Program Leg 199) spanning the Eocene and Oligocene (~50–23 Ma) to reconstruct dissolved silica (DSi) concentrations in deep waters and to examine upper ocean ...
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[1] Using a three-dimensional physical-biogeochemical model, we have investigated the modeled responses of diatom productivity and biogenic silica export to iron enrichment in the equatorial Pacific, and compared the model simulation with in situ (IronEx II) iron fertilization results. In the eastern equatorial Pacific, an area of 540,000 km was enhanced with iron by changing the photosynthetic...
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Because aggregated diatoms sink rapidly through the water column, leaving little time for dissolution, aggregation influences the balance between recycling of biogenic silica (bSiO2) and its sedimentation and preservation at the seafloor. Additionally, aggregation may directly impact dissolution rates of opal. Laboratory experiments were conducted to investigate the influence of aggregation on ...
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A new method uses alluvial paleosols to calculate sediment accumulation rates for thin (25 m) stratigraphic intervals and allows the reliable interpolation of ages for stratigraphic levels within a thick stratigraphic interval bounded by established dates. Sediment accumulation rates calculated for a 650 m composite section in the Eocene Willwood Formation of Wyoming span time intervals ranging...
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ژورنال
عنوان ژورنال: Paleoceanography
سال: 2008
ISSN: 0883-8305
DOI: 10.1029/2007pa001514