Enhanced Cenozoic chemical weathering and the subduction of pelagic carbonate

  title={Enhanced Cenozoic chemical weathering and the subduction of pelagic carbonate},
  author={Ken Caldeira},
THE observed trend of increasing oceanic 87Sr/86Sr ratios during the late Cenozoic led Raymo et al.1 to propose that chemical weathering rates increased at this time as a result of enhanced weatherability of silicate rocks. They suggested that this was due in turn to continential uplift, primarily in the Himalayas and the Andes. Because weathering involves the reaction of silicates with atmospheric carbon dioxide, considerations of changes in weathering rates must take into account the need to… 
Global Chemical Erosion during the Cenozoic: Weatherability Balances the Budgets
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The Cenozoic evolution of the strontium and carbon cycles: relative importance of continental erosion and mantle exchanges
The past variations of the seawater 87Sr86Sr isotopic ratio are related to changes in the relative contribution of the mantle Sr input to the ocean and the Sr supply from continental weathering.
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Neogene continental denudation and the beryllium conundrum
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Large imbalances in the relative net CO2 flux over the last 100 m.y. are obtained from independently derived estimates of CO2 uptake by weathering and organic carbon burial and of CO2 outgassing
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The early Paleozoic carbon cycle
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Modelling the Phanerozoic carbon cycle and climate: constraints from the 87Sr/86Sr isotopic ratio of seawater.
A history of atmospheric carbon dioxide and climate during Phanerozoic time, consistent with the strontium isotopic data, is reconstructed and is shown to be compatible with paleoclimatic indicators, such as the timing of glaciation and the estimates of Cretaceous paleotemperatures.
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Five lines of concrete, quantitative evidence about oceanic chemical composition during the past 65 m.y. can provide insights into the controlling processes and their temporal variations, but the
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