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G. K. Lee

Publications and source records attributed to G. K. Lee.

14 recordsLinked to original sources
USGS2008

Regional Geochemical Results from Analyses of Stream-Water, Stream-Sediment, Soil, Soil-Water, Bedrock, and Vegetation Samples, Tangle Lakes District, Alaska

We report chemical analyses of stream-water, stream-sediment, soil, soil-water, bedrock, and vegetation samples collected from the headwaters of the Delta River (Tangle Lakes District, Mount Hayes 1:250,000-scale quadrangle) in east-central Alaska for the period June 20-25, 2006. Additionally, we present mineralogic analyses of stream sediment, concentrated by panning. The study area includes the southwestward extent of the Bureau of Land Management (BLM) Delta River Mining District (Bittenbender and others, 2007), including parts of the Delta River Archeological District, and encompasses an area of about 500 km2(approximately bordered by the Denali Highway to the south, near Round Tangle Lake, northward to the foothills of the Alaska Range (fig. 1). The primary focus of this study was the chemical characterization of native materials, especially surface-water and sediment samples, of first-order streams from the headwaters of the Delta River. The impetus for this work was the need, expressed by the Alaska Department of Natural Resources (ADNR), for an inventory of geochemical and hydrogeochemical baseline information about the Delta River Mining District. This information is needed because of a major upturn in exploration, drilling, and general mineral-resources assessments in the region since the late 1990s. Currently, the study area, called the 'MAN Project' area is being explored by Pure Nickel, Inc. (http://www.purenickel.com/s/MAN_Alaska.asp), and includes both Cu-Au-Ag and Ni-Cu-PGE (Pt-Pd-Au-Ag) mining claims. Geochemical data on surface-water, stream-sediment, soil, soil-water, grayleaf willow (Salix glauca L.), and limited bedrock samples are provided along with the analytical methodologies used and panned-concentrate mineralogy. We are releasing the data at this time with only minimal interpretation.

Open-File Report↗
USGS2007

Bathymetry and Geology of the Floor of Yellowstone Lake, Yellowstone National Park, Wyoming, Idaho, and Montana

High-resolution, multi-beam sonar mapping of Yellowstone Lake was conducted by the U.S. Geological Survey in conjunction with the National Park Service from 1999 to 2002. Yellowstone Lake is the largest high-altitude lake in North America, at an altitude of 2,357 m with a surface area of 341 km2. More than 140 rivers and streams flow into Yellowstone Lake. The Yellowstone River, which enters at the southern end of the lake into the Southeast Arm, dominates the inflow of water and sediment (Shanks and others, 2005). The only outlet from the lake is at Fishing Bridge where the Yellowstone River flows northward discharging 375 to 4,600 cubic feet per second. The multi-beam sonar mapping occurred over a four-year period beginning in 1999 with mapping of the northern basin, continued in 2000 in West Thumb basin, in 2001 in the central basin, and in 2002 in the southern part of the lake including the Flat Mountain, South, and Southeast Arms.

Scientific Investigations Map↗
USGS1999

Geochemical data for stream-sediment, heavy-mineral-concentrate, and rock samples collected from the Fortyseven Creek gold-arsenic-antimony-tungsten prospect, southwestern Alaska

In the summer of 1991, we conducted a reconnaissance geochemical survey around the Fortyseven Creek Au-As-Sb-W prospect that is located in the southwestern part of the Sleetmute quadrangle. At that time, this project was a small part of a more comprehensive Alaska Mineral Resource Assessment Program (AMRAP) study of the Sleemute quadrangle. AMRAP studies were conducted by the U.S. Geological Survey (USGS) to fulfill requirements of the Alaska National Interests Lands Conservation Act (Public Law 96-487, 1980) to survey certain federal lands to determine their mineral potential. Although AMRAP is no longer in operation, this study represents a small topical study that was conducted during the Sleetmute quadrangle AMRAP study. The objective of the Fortyseven Creek work was to characterize the geochemistry of samples collected downstream from the Fortyseven Creek prospect, as well as mineralized and altered rock samples collected from the prospect. In this report, we describe the samples collected in 1991, the methods used for the analysis of the samples, and the geochemical data for these samples. The data in this report are also available in digital form on computer diskette in Gray and others (1999). An interpretation of these data appears in Gray and others (1998).

Alaska↗
USGS1993

Reconnaissance guidelines for gold exploration in Central Alaska

Distribution of more than 300 gold-bearing samples from the Livengood (Tolovana) and parts of the Fairbanks and Rampart mining districts in central Alaska, USA, indicate that the concentration of gold in placers is spatially related both to structural features and to Late Cretaceous and (or) Tertiary felsic plutons. The regional consistency of these spatial relationships is demonstrated by proximity analysis using a Geographic Information System (GIS), and suggests a genetic association between faults, felsic plutons, and gold occurrences. The local presence of gold within several of the plutons indicates that these are the source of some of the gold. In addition, some gold occurs proximal to faults where plutons are not present, suggesting that some of the gold was also derived from the country rock. We envision a model whereby weakly mineralized solutions, thermally driven by latent plutonic heat, were enriched by circulation through clastic units that may have had a naturally elevated gold background. The resultant enriched solutions were channeled and reconcentrated along or adjacent to large-scale fault systems. Future exploration to define individual target areas should be directed toward areas where Late Cretaceous and (or) Tertiary felsic plutons occur near major faults. ?? 1993.

Journal of Geochemical Exploration↗
USGS1993

Maps showing mineral resource assessment for porphyry and stockwork deposits of copper, molybdenum, and tungsten and for stockwork and disseminated deposits of gold and silver in the Butte 1° x 2° quadrangle, Montana

This report documents the assessment for potential occurrences of undiscovered porphyry and stockwork deposits of copper, molybdenum, and tungsten (porphyry Cu-Mo-W) and stockwork and disseminated deposits of gold and silver (disseminated Au-Ag) in the Butte 1 °X2° quadrangle. The Butte quadrangle, in west-central Montana, is one of the best known mineral producing regions in the U.S. Mining districts in the quadrangle, including the world famous Butte or Summit Valley district, have produced a variety of metallic and nonmetallic mineral commodities valued at more than $6.4 billion (at the time of production). Because of its importance as a mineral producing region, the Butte quadrangle was selected for study by the U.S. Geological Survey under the Conterminous United States Mineral Assessment Program (CUSMAP). Under this program, new data on geology, geochemistry, geophysics, geochronology, mineral resources, and remote sensing were collected and synthesized. The field and laboratory studies were supported, in part, by funding from the Geologic Framework and Synthesis Program and the Wilderness Program. The methods used in this resource assessment for porphyry Cu-Mo-W and disseminated Au-Ag deposits in the quadrangle include a compilation of all data, the development of descriptive occurrence models, and the analysis of data using techniques provided by a Geographic Information System (GIS). This map is one of several maps on the Butte 1 °X2° quadrangle. Other deposit types have been assessed for the Butte quadrangle, and maps (U.S. Geological Survey (USGS) Miscellaneous Investigation Series Maps) for each of the following have been prepared: Vein and replacement deposits of gold, silver, copper, lead, zinc, manganese, and tungsten (Elliott, Wallace, and others, 1992a) and skarn deposits of gold, silver, copper, tungsten, and iron (Elliott and others, 1992b ). Other publications resulting from this study include linear features map (Rowan and others, 1991 ); limonite and hydrothermal alteration map (Rowan and Segal, 1989); mineral occurrence maps (Elliott and others, 1986; Elliott, Loen, and others, 1992); and geologic maps (Wallace, 1987; Wallace and others, 1987).

Montana↗
USGS1982

Geologic reconnaissance and geochemical sampling survey of molybdenum mineralization near Schiestler Peak, Temple Peak Quadrangle, Sublette County, Wyoming

A brief geologic reconnaissance and geochemical survey of molybdenum mineralization near Schiestler Peak, Sublette County, Wyo., indicates that molybdenite occurs in this area as disseminations and blebs in granitic or quartz monzonitic rocks intruded by felsic dikes of similar composition. Samples of stream sediments, panned concentrates from stream sediments, soils, rocks, and water were collected in the geochemical survey. Analytical results show that in reconnaissance, panned concentrates are the best of the sample types used in this study to detect molybdenum mineralization. More detailed analysis of the distribution of the molybdenum is best achieved through the collection of rock samples. Hydrothermal alteration is generally not conspicuous in the study area; however, rock samples that contain molybdenite are usually slightly enriched in silver, copper, lead, and in several instances, gold. Conversely, there appear to be negative associations between molybdenum and zinc and between molybdenum and several of the rare-earth elements. Mo concentrations in the rock samples with no visible molybdenite range from undetectable at a sensitivity of 5 parts per million (ppm) to 700 ppm. Mo content in rock samples containing visible molybdenite ranges from 10 ppm to greater than 2,000 ppm. Stream-sediment values range from undetected to 15 ppm; panned concentrates from undetected to 15 ppm; soils from undetected to 20 ppm. Analyses of the water samples indicate Mo concentrations from 0.8 parts per billion (ppb) to 4.8 ppb. As currently understood, this deposit is not extensive or continuous, but drilling to provide information on the vertical extent of mineralization may alter this opinion.

Open-File Report↗