Abyssal Benthonic Foraminifera and the Carbonate Saturation of Sea Water and a Benthonic Foraminiferal Carbonate Saturation History for the Cape Verde Basin for the Last 550,000 Years

摘要

The distribution of certain Atlantic Ocean benthonic foraminifera is most consistently correlated with the degree of saturation of seawater with respect to calcium carbonate. The relative abundance of cibicidids, miliolids, Uvigerina and Globocassidulina subglobosa increases in saturated water and the relative abundance of Nuttlaides umbonifera increases in undersaturated water. Using this relationship it is possible to recognize changes in the 'paleosaturation' of deep and bottom waters from fossil deep-sea benthonic foraminifera. A carbonate saturation history for the Cape Verde Basin for the last 550,000 years based on benthonic foraminifera shows that undersaturation in the Cape Verde Basin was as great or greater than it is today at 120,000-180,000 yr. B.P.