Benthic foraminifera currents

Unfortunately, equations (3.19) and (3.20), although the best currently available for the data, can only be considered tentative. The weakness lies in the temperature dependence. As mentioned earlier, it is not known whether the results reflect a temperature dependence or a change in the proportion of aragonite to calcite. Another shortcoming in this relationship is that the temperature range of the experiments, 20° to 63°C (if Baertschi s data are included), is well above the temperature at which many organisms secrete carbonate. Because benthic foraminifera have proved very useful in carbon isotopic studies, it is important to have carbon isotopic equilibrium defined over their temperature range. 

Lynch-Stieglitz J., Curry W. B., and Slowey N. (1999a) A geostrophic transport estimate for the Florida Current from the oxygen isotope composition of benthic foraminifera. Paleoceanography 14, 360-373. 

Much of what is currently understood about the Cenozoic history, of deep-sea temperature, carbon chemistry, and global ice volume, has been gleaned from the stable isotope ratios of benthic foraminifera. Benthic foraminifera extract carbonate and other ions from seawater to construct their tests. In many species, this is achieved near carbon and oxygen isotopic equilibrium. Kinetic fractionation effects tend to be small and constant (Grossman, 1984, 1987). As a result, shell fi C and strongly covary with the isotopic... 

Mackensen, A. Licari, L. 2004. Carbon isotopes of live benthic foraminifera from the eastern South Atlantic Ocean sensitivity to bottom water carbonate saturation state and orgnaic matter rain rates. In Wefer, G., Mulitza, S. Ratmeyer, V. (eds) The South Atlantic in the Late Quaternary - Reconstruction of Material Budget and Current Systems. Springer-Verlag, Berlin, Heidelberg, 623 -644. 

VILKS, G. DEONARINE, B. 1988. Labrador Shelf benthic foraminifera and stable oxygen isotopes of Cibicides lobatulus related to the Labrador Current. Canadian Journal of Earth Sciences [Journal Cana-dien des Sciences de la Terre], 25, 1240-1255. 

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