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D. B. Hawkins

Publications and source records attributed to D. B. Hawkins.

7 recordsLinked to original sources
USGS1978

Arsenic in streams, stream sediments, and ground water, Fairbanks area, Alaska

Arsenic concentrations of less than 5 ppb to as large as 1,260 ppb in stream waters and from 5 ppm to 4,000 ppm in stream sediments were found in the Pedro Dome-Cleary Summit area, Alaska. Waters from three of 20 wells sampled had arsenic concentrations exceeding the U.S. Public Health Service recommended limit of 50 ppb. The high arsenic levels are a consequence of arsenic enrichment in the rocks of the area. Placer and lode-gold mining may increase the arsenic content of the waters by exposing arsenic-containing rocks to surface waters and by increasing the load of arsenic-rich sediments in the streams. Finding these disturbingly large concentrations of arsenic in the waters of the Fairbanks area was the major result of this work, inasmuch as a subsequent study (to be published) revealed arsenic concentrations as large as 10 ppm in domestic wells and prompted an extensive study by Federal and State agencies of the health hazard posed by these arsenic-rich waters.

Alaska↗
USGS1969

Gold anomalies and magnetometer profile data, Ester Dome area, Fairbanks district, Alaska

Gold analysis of grab and auger samples of bedrock taken along the new Ester Dome Road reveals that this road cuts several mineralized zones characterized by anomalous concentrations of gold. The results of a magnetometer traverse along this road indicate that the negative magnetic anomalies along the traverse may be correlative with the gold anomalies. The presence of previously unreported gold anomalies indicates that additional prospecting may be warranted.

Open-File Report↗
USGS1968

Gold gradients and anomalies in the Pedro Dome-Cleary Summit area, Fairbanks district, Alaska

Anomalous gold values have been discovered in hydrothermally altered quartz diorite, quartz monzonite, and quartz mica schist at the head of Fox Creek; and in similarly altered quartz diorite in the Granite Creek area. Channel samples across some of these altered zones have produced anomalous gold values over widths which merit further investigation as potential large tonnage low-grade gold deposits. Trace gold gradients have also been detected in the wall rocks adjacent to mineralized veins and in hydrothermal alteration zones in the Pedro Dome-Cleary Summit area. Although most of the gradients may not materially increase the mineable width of the deposit under current economic conditions, such gradients can be used to locate auriferous quartz veins and altered zones by geochemical methods. Gold enrichment is accompanied by anomalous concentrations of arsenic and antimony, and gold bearing quartz veins and altered zones are frequently signaled by peripheral haloes of these metals before trace gold is detectable. Hydrothermally altered and/or sheared zones in both granitic and metamorphic rocks should be carefully prospected, along the trend of the Cleary Antiform.

Open-File Report↗
USGS1959

Plastic standards for geochemical prospecting

Plastic standards for use in geochemical prospecting have been prepared by impregnating a clear thermosetting resin with different amounts of a stable dye or colored metal complex. The colored plastic is molded or subsequently milled into convenient shapes to form standards that are less bulky and more stable than the liquid standards conventionally used in rapid field methods. The use of such standards is limited only by the availability of stable coloring materials. The preparation of plastic standards for use with copper, zinc, tin, and mercury field procedures is described.

Economic Geology↗