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D. M. McKown

Publications and source records attributed to D. M. McKown.

10 recordsLinked to original sources
USGS1995

Sagebrush as a sampling medium for gold exploration in the Great Basin - evaluation from a greenhouse study

Seedlings (Artemisia tridentata subsp, tridentata germinated from seed collected near Preble, Nevada were grown in soils containing Carlin-type disseminated gold ore. After 4 months growth leaves, twigs and stems were combined and analyzed by INAA. Plants grown in soils containing Carlin ore did not accumulate significantly more gold than those growing in control soil. On the other hand, sagebrush grown in soils containing Carlin ores accumulated significantly more arsenic and antimony compared to those grown in control soils. Results suggest that sagebrush would be a good prospecting medium for detecting concealed Carlin-type deposits in the Great Basin if arsenic and antimony are used as the pathfinder elements. Results also suggest that true gold anomalies in sagebrush will be more difficult to separate from aeolian contamination than those for arsenic and antimony in arid environments. -from Authors

Journal of Geochemical Exploration↗
USGS1984

Determination of uranium concentration in water by liquid anion exchange-delayed neutron analysis

Dissolved uranium is selectively removed from 11 of filtered, acidified water using a liquid anion exchange resin (Amberlite LA-1) dissolved in 10 ml of purified kerosene. The organic phase is then analyzed by a standard delayed neutron counting technique. Yields of removed uranium are consistently greater than 90 percent over a measured concentration range of 1.0 to 100 ppb uranium. The absolute detection limit based on 11 of water is 0.06 ppb. Elemental interferences are minimal and the results compare favorably with fluorometric analyses of natural waters.

Journal of Radioanalytical and Nuclear Chemistry↗