Ernest E. Angino

Chemical speciation of Cd, Cu, Pb, and Zn in mixed freshwater, seawater, and brine solutions

A theoretical model was developed to study the chemical speciation of the trace elements Zn, Cd, Cu and Pb aqueous solutions and their responses to variations in ionic strength and complexation. Two mixing solutions were investigated, a freshwater-seawater system and a freshwater-brine system. The brine was a calcium, sodium-chloride solution with a molal ionic strength of two. Trace element associations with the ligands OH−, Cl−, CO2−3, SO2−4, and HCO−3 were considered at pHs from 3.5 to 11.0 at 25°C. In general, the relative importance of the various ligand-trace element complexes can be predicted from a comparison of their stability constants. However, the effect of pH on the importance of a given complex is not readily apparent from the stability constants. Freshwater-seawater mixtures, as might be found in a totally mixed estuary, show that seawater composition is the dominant control on chemical complexing. Chloride complexing is similar for lead and zinc in the freshwater-brine mixtures. This similarity may account in part for the association of lead and zinc in strata-bound ore deposits.

Serpentinization and the Origin of Hydrogen Gas in Kansas

Hydrogen gas occurs in ten Kansas wells near the Mid-Continent rift system. Since 1982, two wells have yielded small amounts of gases containing an average of 29-37 mole % H2, the remainder being chiefly N2 with only traces of hydrocarbons. Isotopic compositions for hydrogen (^dgrD = -740 to -836 ^pmil) imply near-ambient (about 10°C) equilibration temperatures for the gases, which are among the most deuterium-depleted in nature and resemble the H2-rich gases described from ophiolites in Oman. Isotopic values for the Kansas N2 differ slightly from those of the atmosphere, but not enough to rule out an atmospheric origin. Because they are low in CH4 and CO2, expected byproducts of biogenic activity, the gases are probably abiogenic in origin. The existence of such gases near a major rift system, containing mafic rocks, and not far from known kimberlites is consistent with an origin from reactions involving Fe+2 oxidation, for example during serpentinization. Because the gases may be associated with kimberlites and deep-seated rifting, mantle outgassing is possible, but such an origin would be difficult to reconcile with the low isotopic temperatures. The H2 gases from Kansas (and elsewhere) seem to be too low in pressure to have commercial value. However, neither the Kansas gases nor those from other H2 occurrences have been adequately examined to assess their importance as potential resources.

A Geochemical Study of Lakes Bonney and Vanda, Victoria Land, Antarctica

During Deep Freeze 61, highly saline water was found on the bottom of Lakes Vanda and Bonney, Victoria Land, Antarctica. These lakes, perennially ice-covered, have unusually warm waters for such cold environments. In December, 1960, the bottom 20-foot layer of Lake Vanda (

Chemical Stratification in Lake Fryxell, Victoria Land, Antarctica

217 feet\pm 5 feet deep

Effect of leachate solutions from fly and bottom ash on groundwater quality

) had a temperature of

High-Level and Long-Lived Radioactive Waste Disposal

22^{\circ} \pm 2^{\circ} C