Enhanced Cenozoic chemical weathering and the subduction of pelagic carbonate

@article{Caldeira1992EnhancedCC,
  title={Enhanced Cenozoic chemical weathering and the subduction of pelagic carbonate},
  author={Ken Caldeira},
  journal={Nature},
  year={1992},
  volume={357},
  pages={578-581}
}
  • K. Caldeira
  • Published 1 June 1992
  • Environmental Science, Geology
  • Nature
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

The question addressed here is whether global chemical weathering and erosion rates have increased over Cenozoic time in response to uplift of the Himalayas.1–2 Chemical weathering of the continents

Balancing the Cenozoic carbon and alkalinity cycles: Constraints from isotopic records

A simple model of the carbon, alkalinity and strontium cycles is built up and used to interpret the carbon and strontium isotopic evolution of seawater over the Cenozoic as recorded in marine

The Himalayas, organic carbon burial, and climate in the Miocene

  • M. Raymo
  • Environmental Science, Geography
  • 1994
Cooling ages of rock in the Himalayas imply that rapid exhumation between the Main Central thrust system and the South Tibetan detachment system occurred between 21 and 17 Ma. The generation of

Neogene continental denudation and the beryllium conundrum

A beryllium cycle model is presented whose results show that variations in the 9Be weathering flux are counterbalanced by near-coastal scavenging while the cosmogenic 10Be flux from the upper atmosphere stays constant, and predicted seawater 10Be/9Be ratios remain nearly constant even when global denudation and Be weathering rates increase by three orders of magnitude.

Geochemical consequences of increased Late Cenozoic weathering rates and the global CO2 balance since 100 Ma

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

Synchronous changes in seawater strontium isotope composition and global climate

THE 87Sr/86Sr ratio of sea water has increased gradually over the past 40 Myr, suggesting a concomitant increase in global chemical weathering rates1–6. Recently, Dia et al.7 analysed a 250-kyr

Modulation of Late Cretaceous and Cenozoic climate by variable drawdown of atmospheric pCO 2 from weathering of basaltic provinces on continents drifting through the equatorial humid belt

Abstract. The small reservoir of carbon dioxide in the atmosphere (pCO2) that modulates climate through the greenhouse effect reflects a delicate balance between large fluxes of sources and sinks.

The early Paleozoic carbon cycle

...

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