Proxy methods geochemical

VoUcman J. K., and Wakeham S. (2001) Precision of the current methods to measure the alkenone proxy U 7 and absolute alkenone abundance in sediments results of an interlaboratory comparison study. Geochem. Geophys. Geosys. 2, paper 2000GC000141. 

Usually, alkalinity is actually the ultimate parameter that is subject to a procedure of genuinely chemical titration, in this regard as a proxy parameter for carbonate. A new spectropho-tometric method for the determination of alkalinity was proposed by Sarazin et al. (1999). Mostly, alkalinity will be, for reasons of simplification, set equal to the total carbonate concentration, although a number of other substances in pore water will contribute to the titration of alkalinity as well. Most geochemical model programs (cf Chap. 15) foresee the input of titrated alkalinity as an alternative to the input of carbonate. The model program will than calculate the proportion allo-catable to the different carbonate species. 

C., Prahl, F., Quinn, J., Rontani, J.-F., Rostek, F., Rullkotter, J., Sachs, J., Blanz, T, Sawada, K., Schulz-Bull, D., Sikes, E., Sonzogni, C., Ternois, Y., Versteegh, G, Volkman, J.K. and Wakeham, S., 2001. Precision of the current methods to measure the alkenone proxy U and absolute alkenone abundance in sediments Results of an interlaboratory comparison study. Geochem. Geophys. Geosyst., 2 Paper number 2000GC000141. 

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