『Abstract
The carbon cycle model GEOCARBSULF is extended by dividing the
weathering of silicates into volcanic and non-volcanic rocks.
The proportion of volcanic weathering is calculated as a function
of time from the oceanic record of 87Sr/86Sr.
The volcanic proportion is then used to modify the equations for
calculating atmospheric CO2 by the addition
of a new non-dimensional volcanic weathering factor. The effect
of uplift and physical erosion on weathering is also modified
by using only the distribution over time of the abundance of sandstones
and shales, and not Sr isotopic data that had been used previously.
Results indicate moderate change from GEOCARBSULF in the distribution
of atmospheric CO2 over Phanerozoic time. This includes an increased
minimum in CO2 during the Late Ordovician, in agreement with the
presence of a continental glaciation at that time, and a shift
of maximum Mesozoic values from the Jurasic to the Early Vretaceous.』
Introduction
Method
Results and discussion
Acknowledgments
Appendix
Derivation of equation (1)
References