The salinity of hypersaline brines: Concepts and misconceptions
- David A. Anati
- … show all 1 hide
Rent the article at a discountRent now
* Final gross prices may vary according to local VAT.Get Access
Some widespread misconceptions about salinity are pointed out, explained and commented on. Definitions, units, and methods of salinity determination recommended for brines of moderate salinities may become unsuitable for highly saline brines. Various salinity units are examined and commented on, and density at a precisely monitored temperature is chosen as the preferable “substitute parameter” for salinity determination of hypersaline brines. It is shown that ambient air density during pycnometric measurements must be known as accurately as required of the brine's density, and that its value must be added to the direct pycnometric measurement. Variations of atmospheric pressure at the time of pycnometry must be taken into account if greater than 15 mB. For a salinity accuracy of ±0.02 per mille, as required for some physical and chemical studies, the temperature of the sample during salinity measurement must be monitored with an accuracy of at least 0.04°C. A definite curve in the ρ-S plane, corresponding to the conversion of salinity to density at a fixed temperature, andvice-versa, does not exist if the brine is saturated in one of its salts. Non-linearity in the equation of state is shown to affect the surface level drop due to evaporation; the effect is negligible at low salinities, but a 10 per cent correction is already required at the salinity found in the northern Red Sea (41 per mille). Reliable reference points for the conversion of absolute salinity to density of highly saline brines are not known, at present, as accurately as desirable; pending the accurate determination of such reference points, a substantial dilution of hypersaline brines (for the purpose of adapting them to conductivity measurements) would multiply the error range by more than a hundred fold. On the other hand, a minute dilution of hypersaline brine samples to prevent salt crystal formation is possible and would not bring about any major increase of the error range in their density (salinity) determination.
- Anati, D.A. 1993. How much salt precipitates from the brines of a hypersaline lake? The Dead Sea as a case study. Geochim. et Cosmochim. Acta 57: 2191–2196. CrossRef
- Anati, D.A. and Stiller, M. 1991. The post-1979 thermohaline structure of the Dead Sea and the role of double-diffusive mixing. Limnol. Oceanogr. 36: 342–354.
- Forschhammer, G. 1865. On the composition of sea-water in different parts of the ocean. Phil. Trans. Royal Soc. London 155: 203–262.
- Gavrieli, I., Starinsky, A. and Bein, A. 1989. The solubility of halite as a function of temperature in the highly saline Dead Sea brine system. Limnol. Oceanogr. 34: 1224–1234. CrossRef
- Kaushansky, P. and Starobinet, S. 1982. A temperature gradient column for the rapid measurement of the density of brines. Marine Chemistry 11: 289–292. CrossRef
- Krumgalz, B.S. and Millero F.J. 1982a. Physico-chemical study of the Dead Sea Waters. I. Activity coefficients of major ions in the Dead Sea water. Marine Chemistry 11: 209–222. CrossRef
- Krumgalz, B.S. and Millero F.J. 1982b. Physico-chemical study of the Dead Sea Waters. II. Density measurements and equation of state of Dead Sea water at 1 atm. Marine Chemistry 11: 477–492. CrossRef
- Lazar, B. 1982. Geochemical studies of heavy metals in natural waters. Ph.D. thesis the Hebrew university, Jerusalem, 174, 166 pp.
- Levi, Y., Bodenheimmer, Y. and Varshawski, Y. 1984. Optical Measurements in the Dead Sea. Jerusalem College of Technology.
- Marcet, A. 1819. On the specific gravity, and temperature, in different parts of the ocean, and particular seas; with some account on their saline content. Philosophical Transactions of the Royal Society of London 10: 161–208.
- Neumann, G. and Pierson, W.S. 1966. Principles of Physical Oceanography. Prentice-Hall Inc., 323 pp.
- Oren, A. and Anati, D.A. 1996. Termination of the Dead Sea 1991–1995 stratification: Biological and physical evidence. Isr. J. Earth Sci 45: 81–88.
- Steinhorn, I. 1981. A Hydrographical and Physical study of the Dead Sea during the destruction of its long-term meromictic stratification. PhD thesis, Weizmann Institute, Rehovot, 323 pp.
- Stiller, M., Kaushansky, P. and Carmi, I. 1983. Recent climatic changes recorded by the salinity of pore waters in the Dead Sea sediments. Hydrobiologia 103: 75–79. CrossRef
- Sverdrup, H.U. 1983. Vereinfachtes Verfahren zum Berechnung der Druck und Massenverteilung im Meer. Geophys. Pub. 10(1), Oslo.
- Unesco (1976) Technical papers in marine sciences, 24.
- Williams, W.D. and Sherwood, J.E. 1994. Definition and measurement of salinity in salt lakes. Int. J. Salt Lake Res. 3: 53–63. CrossRef
- The salinity of hypersaline brines: Concepts and misconceptions
International Journal of Salt Lake Research
Volume 8, Issue 1 , pp 55-70
- Cover Date
- Print ISSN
- Online ISSN
- Kluwer Academic Publishers
- Additional Links
- Dead Sea
- equation of state
- David A. Anati (1)
- Author Affiliations
- 1. Institute of Earth Sciences, Hebrew University in Jerusalem, Givat Ram, 91904, Jerusalem, Israel