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R.M. Garrels

Publications and source records attributed to R.M. Garrels.

5 recordsLinked to original sources

Glass electrodes sensitive to divalent cations

Glass electrodes suitable for measurement of divalent cations have been made and tested. Empirical and theoretical electrode equations have been presented to describe electrode behavior in a variety of aqueous solutions. Most electrodes show response interpretable as showing nearly ideal solid-solution behavior of the cations in the glass surface. The electrodes should be useful in the measurement of divalent-cation activities in natural waters and biological fluids, and useful in general analytical chemistry.

Science

Equilibrium distribution of dissolved sulphur species in water at 25°C and 1 atm total pressure

The E h -pH diagrams for the equilibrium concentrations in aqueous solution at 25°C of native sulphur and all the various sulphur-containing ions and acids from which the ions are produced have been constructed for systems having a total sulphur concentration of 0.1 molar. The composite of these diagrams indicates that elemental sulphur, H 2 S, HS − HSO 4 − and SO 4  are the species that predominate in the environments that might be found in nature. This indication is in agreement with the composition of all sulphur-containing minerals.

Geochimica et Cosmochimica Acta

Is Carbon dioxide an ore-forming fluid under shallow-earth conditions?

A review of some of the physical-chemical properties of CO 2 and of the system CO 2 --H 2 O indicates that under some shallow-earth conditions CO 2 can exist as a separate phase with a density approximately that of water. The effect of dissolved neutral or acid salts on the solubility of CO 2 in H 2 O is not large. Carbonates, oxides, and silicates, through reactions with a CO 2 -saturated water phase, will eventually cause the disappearance of a CO 2 phase. The prevalence of CO 2 in the earth's crust is attested by its abundance in natural gases and fluid inclusions in minerals. Some of the characteristics of uranium ores of the Colorado Plateau are not incompatible with the assumption that deposition was from a fluid CO 2 phase.

Economic Geology