Changes in Ocean Chemistry

Glacial/Interglacial

Stratigraphy of a Indian Ocean Core.

During Glacial:

Better preservation of carbonate in deep water Calcite Compensation Depth CCD > 4000 m

Aquatic CO2 concentration (Cadmium proxy) less during glaciation (Boyle, 1989)
lysocline deeper, increases capacity of all seawater to disolve CO2

Disolution produces significant changes in assemblages of marine organisms

The composition of the ocean has not been consistent on timescles longer than glacial/interglacial.
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  • Martinson, D.G., Pisias,N.G. Hays, J.D. Imbrie, J., Moore, T.C., Jr., and Shackleton, N.J. 1987. Age dating and the orbital theory of the Ice Ages: development of a high-resolution 0 - 300,000 year chronostratigraphy. Quaternary Research 27:1-29.