Now showing items 21-40 of 229

    • Natural revegetation of placer mined lands of interior Alaska II

      McKendrick, J.D., Neiland, B.J., and Holmes, K. (University of Alaska Mineral Industry Research Laboratory, 1980)
      To the uninitiated eye an aerial photo of Fairbanks’ surrounding area includes patches of what might appear to be the channels left by the workings of a bark beetle grub. These series of parallel mounds with sequences of smaller undulations on their surfaces are actually composed of coarse gravel and are the product of some forty years of gold dredging. Started in 1928, dredging was concentrated in several of the tributary valleys of the Tanana River and Goldstream Creek. Some of these tailings piles support lush growth while others are relatively bare. At present, no ecologically oriented studies, either qualitative or quantitative, have been published concerning the gold dredge tailings. It was therefore the intent of this study to obtain a broad picture of the present stage of revegetation, in order that further ecological work and, hopefully, assisted rehabilitation may be facilitated.
    • Placer mining in Alaska II

      Wolff, E.N., Robinson, M.S., Cook, D.J., and Thomas, B. (University of Alaska Mineral Industry Research Laboratory, 1980)
      During July, August and September, 1979, a team from the Mineral Industry Research Laboratory visited a number of placer mining districts that could be reached by automobile, hence at a reasonable cost for transportation. These districts yielded varying amounts of information that will be of value to the industry. The district visited were: 1. Fairbanks, 2. Circle (Birch Creak), 3. Livengood (Tolovana), 4. Manley Hot Springs, 5. Fortymile, 6. Klondike, 7. Kantishna, 8. Yentna.
    • Mineral investigations of D-2 lands in the Philip Smith Mountains and Chandler Lake quadrangles

      Metz, P.A. and Robinson, M.S. (University of Alaska Mineral Industry Research Laboratory, 1979)
      Eight hundred and sixty-five stream sediment samples were collected over an area of approximately 2,120 square kilometers (828 square miles) in the Chandler Lake and Philip Smith Mountains quadrangles (Fig. 1). The samples were analyzed by atomic absorption methods for Cu, Pb, Zn, Ag and Mo. Statistical reduction of the data resulted in the definition of 86 anomalous samples. The majority of the anomalous samples were from streams draining either the Hunt Fork Shale, Kanayut Conglomerate, or the Lisburne Group. The anomalous samples are grouped in ten separate areas; eight of these areas warrant additional field examination. The number of geochemical anomalies within the area indicates that region has good potential for copper, lead and zinc sulfide mineral deposits.
    • Baseline geochemical studies for resource evaluation of D-2 Lands - geophysical and geochemical investigations at the Red Dog and Drenchwater Creek mineral occurrences

      Metz, P.A., Robinson, M.S., and Lueck, L. (University of Alaska Mineral Industry Research Laboratory, 1979)
      Major zinc, lead and barite mineralization has been discovered at Red Dog and Drenchwater Creeks in the DeLong Mountains of north-western Alaska. The host rocks for the mineral occurrences are carbonates, cherts, shales, and dacitic volcanic rocks of the Mississippian Lisburne Group. The host rocks are deformed in a narrow belt of imbricate thrust sheets that extend from the Canadian border to the Chukchi Sea. The rocks strike generally east-west and dip to the south. The sulfide minerals occur as stratiform mineralization parallel to bedding planes, as breccia fillings and vein replacements, and as disseminations in the various host rocks. The primary ore minerals are sphalerite, pyrite, pyrrhotite, and galena. Barite occurs as massive beds up to 90 meters (300 feet) thick at Red Dog Creek and as nodules, veinlets, and disseminations at Drenchwater Creek. Close spaced soil sampling, mercury vapor sampling, and magnetic and radiometric surveys were conducted over the areas of exposed sulfide mineralization to test the response of these techniques to these types of deposits in northern Alaska. There is potential for additional deposits of this type in the Lisburne Group of the entire northern Brooks Range. These techniques provide a rapid low cost method for the discovery and preliminary evaluation of these types of mineral occurrences in northern Alaska.
    • Evaluation of the mineral resources of the pipeline corridor, phases i and ii

      Robinson, M.S. and Metz, P.A. (University of Alaska Mineral Industry Research Laboratory, 1979)
      In accordance with U. S. Bureau of Mines (U.S.B.M.) Grant No. G0166180 entitled, “Evaluation of the Mineral Resources of the Pipeline Corridor”, the Mineral Industry Research Laboratory (M.I.R.L.), of the University of Alaska, completed an examination of the mineral resource potential of the federal utility corridor established for the trans-Alaska pipeline. The contract was completed under the direction of the Principal Investigator, Paul A. Metz and the Associate Investigator, Mark S. Robinson.
    • Some implications for Alaska of petroleum development on the Norwegian Continental Shelf

      Lynch, D.F. and Johansen, N.I. (University of Alaska Mineral Industry Research Laboratory, 1978-06)
      In January 1978, Senator Mike Gravel travelled in Norway to obtain information on Norwegian reactions to petroleum development on the continental shelf of the North and Norwegian Seas. This report presents some implications of Norwegian experiences which may be relevant to Alaska as developed by two University of Alaska professors who accompanied Senator Gravel and his assistant C. Deming Cowles.
    • Sulphur isotopic evidence for the genesis of the Au-Ag-Sb-W mineralization of the Fairbanks mining district, Alaska

      Metz, P.A. (University of Alaska Mineral Industry Research Laboratory, 1984-10)
      Sulphur dioxide from sulphides was extracted for analysis by oxidation with Cuprous oxide at 1070º C, using essentially the method described by Robinson and Kusakabe (1975). The isotopic analyses of the purified sulphur dioxide were made on a modified Micromass 602 mass spectrometer with heated inlet system. The results were corrected for isobaric interference assuming a constant oxygen isotopic content and instrumental crosstalk (Coleman, 1977; 1980) and expressed in conventional del notation with respect to the Canon Diablo meteoritic troilite standard.
    • Determination of molybdenum in geological materials

      Rao, P.D. (University of Alaska Mineral Industry Research Laboratory, 1971-09)
      This paper will describe a method for the determination of molybdenum in geological materials. It is known that molybdenum as molybdate or phosphomolybdate ion can be extracted using the liquid ion exchanger, Aliquat 336 (methyl tricapryl ammonium chloride, available from General Mills, Inc. Kankakee, Ill.). Aliquat 336 has been used for analytical separation of gold, tungsten, and actinide-lanthanide elements.
    • The determination of titanium in titaniferous magnetite ores by atomic absorption spectrophotometry

      Rao, P.D. (University of Alaska Mineral Industry Research Laboratory, 1972-03)
      Amos and Willis (1) first investigated the use of nitrous oxide for the determination of titanium. They found that the presence of HF and iron enhance the absorption of titanium. They recommended “much more extensive investigation before a practicing chemical analyst can determine this element in a routine fashion by atomic absorption.” Various authors (2, 3, 4, 5, 6) have investigated titanium by atomic absorption and have recommended a number of different procedures to remove interference. In attempting to analyze lithium metaborate fusions (7, 8) of titaniferous magnetite ores of Alaska by atomic absorption, it was found that the interferences are not completely removed by any single approach suggested in the literature. Silicon, iron and aluminum could vary widely between samples and an approach was needed that would completely eliminate interference effects of all these elements, without having to match the gross matrix composition of samples and standards.
    • Solvent extraction procedure for the determination of tungsten in ores

      Rao, P.D. (University of Alaska Mineral Industry Research Laboratory, 1970-11)
      Atomic absorption methods have not been widely used for the determination of tungsten in ores due to its low sensitivity in aqueous solutions (1). A method has now been developed for solvent extraction of tungsten, making rapid determination of tungsten at low concentrations possible. It was found that tungstates, when converted to phosphotungstates, can be effectively extracted into di-isobutyl ketone (2-6 dimethyl - 4 - heptanone) (DIBK) containing Aliquat 336 (methyl tricapryl ammonium chloride from General Mills). This system was effectively used for the extraction of gold from cyanide solutioins (2). Even in aqueous solutions, phospho-tungstates give greater sensitivity (37 µg/ml for 1% absorption) compared to simple tungstates (63 µg/ml for 1% absorption). Standard tungsten solutions for extraction studies were prepared by converting aqueous solutions of sodium tungstate to sodium phospho-tungstate by boiling with ortho phosphoric acid. A Perkin-Elmer Model 303 atomic absorption spectrophotometer was used with a nitrous oxide-acetylene flame at a wavelength of 4008.75 A.
    • Determination mercury in Alaskan coals by flameless atomic absorption

      Rao, P.D. (University of Alaska Mineral Industry Research Laboratory, 1973)
      An oxygen combustion, double gold amalgamation system is constructed for the determination of mercury in Alaskan coals. Solutions have been found for certain problems in design and operation. The effect of operating variables have been thoroughly evaluated and analytical procedure is outlined. The system involves combustion of goal in an oxygen atmosphere and amalgamating mercury on gold coils. The amalgamated mercury is released by heating and measured in an atomic absorption cell.
    • Characterization of Alaska's coals

      Rao, P.D. (University of Alaska Mineral Industry Research Laboratory, 1974)
      Coal characterization is a systematic determination of those properties of coal, or of its constituents, that affect its behavior when used. It will help in planning for recovery and use of the extensive Alaskan coal deposits, which have proven reserves of 130 billion tons. This estimate is of necessity based on widely scattered outcrops and meager drill hole data, and the reserves in the Cook Inlet region and the Northern Alaska field are considered to be several fold this figure.
    • Current state-of-the-art in drying low-rank coals

      Rao, P.D. and Wolff, E.N. (University of Alaska Mineral Industry Research Laboratory, 1976)
      Research on drying of low-rank coals, such as lignites and subbituminous coals, has been conducted for nearly half a century. Although partial drying of Dakota lignite is practiced for freeze-proofing by mixing partially dried coal with run-of-mine coal, full scale drying of low rank coals has never been practiced commercially in this country. The reasons are: ( 1 ) drying of low rank coals by conventional methods results in severe degradation of coal particles; (2) dried coals are thus dusty and difficult to handle; (3) reabsorption of moisture in storage and transit defeats the drying process. In addition the dry coal particles will react with ambient oxygen, and heat up enough to ignite. It appears that large-scale development of Alaskan coals may have to await solutions to these problems. Our Mineral Industry Research Laboratory at the University of Alaska is making a comprehensive literature search seeking solutions to these problems and identifying areas of research that should be undertaken.
    • Resume of high capacity gravity separation equipment for placer gold recovery

      Mildren, Jim. (University of Alaska Mineral Industry Research Laboratory, 1975-01)
      The phenomenal and meteoric rise in gold prices in the past few years has stimulated a renewed interest in domestic gold mining and many deposits once considered valueless or at best marginal at past gold prices are now potentially mineable at a profit and will become even more attractive if new and more appropriate technology can be found and applied. There have been many new innovations in gravity separation technology since the days of the gold dredge, and most of these have been developed outside of the U. S., where placer deposits are being mined and processed for various other minerals such as rutile, illeminite, zircon, cassiterite and even diamonds. Many of these newer methods could be very profitably applied to gold recovery in many present day placer or sand and gravel operations.
    • Mining in Alaska - environmental impact and pollution control

      Johansen, N. I. (University of Alaska Mineral Industry Research Laboratory, 1975)
      Environmental factors affecting mining are difficult to establish in Alaska due to the absence of large scale hard rock mining activities at the present time. Currently, experience is gathered from (and to a large degree based on) construction of above ground facilities such as roads, pipelines, and buildings. Past mining activities appear to have had little lasting effect on the natural environment, the exceptions being mine tailings and surface structures. This report, sponsored by the U. S. Bureau of Mines, present general engineering activities, considers the interaction of permafrost and underground mining, summarizes available literature and indicates possible environmental problems that might be encountered in Alaska based on Scandinavian experiences in large-scale northern mining operations. How the Scandinavians are solving their problems is also discussed.
    • Land Application of Domestic Sludge in Cold Climates

      Johnson, Ronald A. (University of Alaska, Institute of Water Resources, 1979)
      Aerobically digested sludge from the Fairbanks sewage treatment plant was worked into the soil on several plots at the University of Alaska in the summer of 1978. Some of the sludge had been air dried for up to six months prior to application while some was taken directly from the thickener. Applications varied from 12 to 100 tons of solids/acre. For sludge applied in July and August, the fecal coliform count decayed by several orders of magnitude by the middle of September.. There was no significant movement of fecal coliform bacteria either vertically or laterally. Lime was used to raise the pH of one plot to 12, completely killing the fecal coliform bacteria within several days. The nutrient distribution demonstrated the potential for enriching soils by sludge addition. The main purpose of the study was to investigate the feasibility of this concept for remote military sites. Air drying followed by land application may represent a viable means of sludge disposal.
    • Analysis of Alaska's water use act and its interaction with federal reserved water rights

      Curran, Harold J.; Dwight, Linda Perry (University of Alaska, Institute of Water Resources, 1979-02)
      Since the passage of Alaska's Water Use Act in 1966, the amount of water required by Alaska's growing population and resource development has increased very rapidly. The need to review the adequacy of existing water use laws and their administration has been expressed both by those trying to comply with regulations and by those attempting to enforce standards and permit requirements. This report summarizes the historical development of the doctrine of prior appropriation in Alaska. The statutory authority, regulations, and administration of Alaska's Water Use Act by the Alaska Department of Natural Resources are presented. Overlapping state agency authorities are discussed, and existing and proposed regulations are analyzed. The application of federal reserved water rights to Alaska and the status of quantification of these rights is explained. The report presents options for the State of Alaska to manage water use on federal lands, and for preserving minimum stream flows for maintenance of fish and wildlife habitats.
    • Snowmelt -frozen soil characteristics for a subarctic setting

      Kane, Douglas L.; Seifert, Richard D.; Fox, John D.; Taylor, George S. (University of Alaska, Institute of Water Resources, 1978-01)
      The pathways of soil water in cold climates are influenced, in addition to the normal forces, by the presence of permafrost and the temperature gradients in the soil system, whereas the infiltration of surface water into the soil system is a function of moisture levels, soil type and condition of the soil (whether it is frozen or not). Snowfall, with subsequent surface storage over a period of several months, typifies Alaskan winters. This snowfall often accounts for 50 per cent or more of the annual precipitation, with ablation occurring over a time span of 2 to 3 weeks in the spring. The melt period represents an event when large quantities of water may enter the soil system; the possibilities exist for recharging the groundwater system, or else generating surface runoff. The objective of this study was to determine the magnitude of potential groundwater recharge from snowmelt. Instrumentation was installed and monitored over two winter seasons to quantify the accumulation and ablation of the snowpack. Thermal and moisture data were collected to characterize the snow pack and soil conditions prior to, during, and following the ablation. Lysimeters were installed at various depths to intercept soil water. The volume of potential areal recharge for 1976 was 3.5 cm and for 1977 was 3.0 cm, which represented about 35 per cent of the maximum snowpack content. It is concluded that permafrost-free areas can contribute significantly to groundwater recharge during snowmelt ablation.
    • Treatment of Low Quality Water by Foam Fractionation

      Murphy, R. Sage (University of Alaska, Institute of Water Resources, 1968)
      The removal of iron from Alaskan groundwaters by a foam fractionation technique has been shown to very effective. Finished waters with less than 0.2 mg/l iron have been produced from raw waters containing in excess of 25 mg/l. Ethylhexadecyldimethylammonium bromide was used as the principal foaming agent. Low temperature oxidation of the ferrous iron tended to interfere with the removal rates, but high temperature oxidation followed by low temperature fractionation did not exhibit the same adverse influence. All experiments were performed in four-liter laboratory batch columns. For the Alaskan environment batch processing is thought to have advantages over continuous processes because of the need for uncomplicated equipment.
    • The Biochemical Bases of Psychrophily in Microorganisms: A Review

      Miller, Ann P. (University of Alaska, Institute of Water Resources, 1967)