• Geodatabase development and GIS based analysis for resource assessment of placer platinum in the offshore region of Goodnews Bay, Alaska

      Oommen, Thomas (2006-12)
      Goodnews Bay, southwest Alaska, is known for extensive Pt reserves that have their source in the neighboring Red Mountain. The reserves potentially extend offshore into the Bering Sea. This study aims at developing a geodatabase to integrate all offshore platinum related data collected by researchers and agencies in the past, with the intent to identify data gaps. Based on these data gaps 49 new areas were sampled for Pt and geophysical data were collected in summer 2005. Spatial distribution map for offshore Pt was created using a new Multiple Regression Pattern Recognition Technique (MRPRT) that gave an R²=0.76, a significant improvement from standard GIS based geospatial techniques. Four potential Pt exploration areas were delineated, including one area where drowned ultramafics and buried alluvial channels co-occur. Coastal currents influenced the surficial platinum accumulations, and no clear relation between Pt distribution and sand bars in the far offshore could be established.
    • A geohydrologic analysis of an upland-bedrock aquifer system: applications to interior Alaska

      Youcha, Emily K. (2003-05)
      Ester Dome, an upland-dome bedrock aquifer system, located nearby Fairbanks, Alaska, was studied to identify important geohydrologic processes occurring in Interior upland aquifer systems. The ground-water dynamics at Ester Dome are complex due to the fractured nature of the aquifer system. The geology at Ester Dome consists of metamorphic and igneous rocks. Valley bottom deposits include gravels and loess. The flow pattern of the dome aquifer system is radial. Ground-water flows from a central high elevation recharge area and discharges into lakes, streams, and wetlands in the valley bottoms. The primary form of recharge to the bedrock aquifer is from spring snowmelt. Snow water equivalent and snow depth increases with elevation. Ground-water levels were observed at fifty sites on Ester Dome for two years. Water levels in wells at high elevations or locations with no silt or permafrost coverage show seasonal fluctuations. However, ground-water levels in the valley bottoms show little seasonal fluctuations, except wells that penetrate gravel deposits and have no overburden. A ground-water flow model was developed to aid in the understanding of these geohydrologic processes. The ground-water flow model shows recharge and bedrock hydraulic conductivity as the most sensitive parameters.
    • Geologic description and reservoir modeling of a Jurassic aged, low permeability, light oil reservoir, northern coastal plain, Alaska

      Newell, Jack Robert (2001-05)
      The objectives of the study include the analysis of the geologic description and reservoir modeling of a Jurassic aged, low permeability, light oil reservoir on the northern coastal plain of Alaska. The methodology of the study was to use a reservoir simulation model to evaluate the performance and cumulative recovery of the reservoir under primary depletion and a water injection process. Results of the simulation showed a primary recovery of 15.9 %OOIP of oil by solution gas drive. The results of thee simulation by a water displacement process showed that 41.9 %OOIP oil could be recovered with a production of 38.5 %HCPV of the injected water. This study has an application in determining estimates of the design paramaters for surface facilities required for the development of the field.
    • Geological modeling and reservoir simulation of Umiat: a large shallow oil accumulation

      Oraki Kohshour, Iman; Dandekar, Abhijit; Hanks, Catherine; Ahmadi, Mohabbat; Dandekar, Abhijit (2013-05)
      Current high oil price and availability of new technologies allow re-evaluation of oil resources previously considered uneconomic. Umiat oil field is one such resource: a unique, shallow (275-1055 feet), low-pressure (200-400 psi) reservoir within the permafrost zone located north of the Arctic Circle, 80 miles west of Trans Alaska Pipeline System (TAPS) with an estimated 1.5 billion barrel of oil-in-place. This thesis presents a reservoir model that incorporates recently identified permeability anisotropy patterns within the Cretaceous Nanushuk sandstone reservoir to evaluate various potential mechanisms such as horizontal wells and immiscible gas injections. The simulation model focuses on the Lower Grandstand which is identified as a better reservoir rock. The reservoir temperature is assumed at 26 OF and gas is injected at the same temperature to maintain equilibrium with the permafrost and prevent any well integrity problems. An optimum horizontal well length of 1500 ft was found and applied for all simulation cases. The simulation results show that with 50 years of lean gas injection, recovery factors for the base case and case of 600 psi injection pressures are 12% and 15%, respectively, keeping all other parameters constant.
    • Geology and Geochemistry of the Ship Creek and Monashka Creek reservoirs, Southcentral Alaska

      Hawkins, Daniel B.; Nelson, Gordon L. (University of Alaska, Institute of Water Resources, 1976-01)
      Graywacke from the Ship Creek watershed, dissolves incongruently in distilled water. The dissolution appears to follow a first-order rate law which in integrated form is: k = -2.303/t log No-Q/No where No is the concentration in ppm of Ca, Mg, Na or K in the graywacke, Q is the total quantity of these ions leached in time t(days), k is the rate constant in days-1. Experimentally derived rate constants for the dissolution of graywacke in distilled water at 5oC are log k+2CA, -4.128 day-1; log k+2Mg, -6.174 day-1; log k+Na, -5.800 day-1; and log k+K, -5.249 day-1. The above constants are for 40 to +100 mesh graywacke. A surface area correction term must be inserted in the above equation if it is applied to a different size fraction. Using the above equation and rate constants, the chemical composition of a water in contact with graywacke was calculated. With the exception of magnesium, the agreement between the calculated composition and that of Ship Creek water was good. Assuming that the groundwater in the Ship Creek watershed contacts about 1.5X104cm2 graywacke per liter, 120 to 360 days are required at 5oC to produce the concentration of ions observed in Ship Creek. Release of exchangeable H+ from the soil mat to the reservoir water will not significant1y lower the pH of the water. Leaching of heavy metals from sulfides contained in the bedrock of the two watersheds does not pose a water quality hazard. Lineaments in the bedrock at Monashka Creek may provide channels through which water may seep from the reservoir. These are not expected to pose a problem in retaining water in the reservoir, but they may result in small, new springs down grade from the reservoir.
    • Geology of a subarctic, tin-bearing batholith - Circle Hot Springs, Alaska

      Wilkinson, Kathy (University of Alaska Mineral Industry Research Laboratory, 1987)
      A small batholith (56mi2) outcrops approximately 94 miles northeast of Fairbanks. It occurs in a historically rich area for placer gold. Additionally, placer tin has been recorded in the creeks that flow through or adjacent to the batholith.
    • Geophysical and Biological Reconnaissance of Rock Habitats in Western Camden Bay, Beaufort Sea, Alaska

      Dunton, K. H.; Schonberg, S. V.; Schell, Donald M. (University of Alaska, Institute of Water Resources, 1983-05)
      This report presents the results of a 10-day geophysical and biological survey in western Camden Bay, in the Alaskan Beaufort Sea. The primary objective of this survey was to confirm the existence of boulders and cobbles on the seafloor as reported by Barnes (1981, 1982). The survey area extended from the eastern edge of the Canning River (mud flat area) to Kangigivik Point and seaward to the 14m contour line (Fig. 1). A solid boundary of pack ice prevented any survey work seaward of the 14m contour. We had proposed to examine the seabed to the 18m contour.
    • Geophysical Applications for Arctic/Subarctic Transportation Planning

      Schnabel, William E.; Fortier, Richard; Kanevskiy, Mikhail; Munk, Jens; Shur, Yuri; Trochim, Erin (Alaska University Transportation Center, 2014-07)
      This report describes a series of geophysical surveys conducted in conjunction with geotechnical investigations carried out by the Alaska Department of Transportation and Public Facilities. The purpose of the study was to evaluate the value of and potential uses for data collected via geophysical techniques with respect to ongoing investigations related to linear infrastructure. One or more techniques, including direct-current resistivity, capacitive-coupled resistivity, and ground-penetrating radar, were evaluated at sites in continuous and discontinuous permafrost zones. Results revealed that resistivity techniques adequately differentiate between frozen and unfrozen ground, and in some instances, were able to identify individual ice wedges in a frozen heterogeneous matrix. Capacitive-coupled resistivity was found to be extremely promising due to its relative mobility as compared with direct-current resistivity. Ground-penetrating radar was shown to be useful for evaluating the factors leading to subsidence in an existing road. Taken as a whole, the study results indicate that supplemental geophysical surveys may add to the quality of a geotechnical investigation by helping to optimize the placement of boreholes. Moreover, such surveys may reduce the overall investigation costs by reducing the number of boreholes required to characterize the subsurface.
    • GeoTechnical Investigations for the Dalton Highway Innovation Project As A Case Study of the Ice-Rich Syngenetic Permafrost

      Shur, Yuri; Kanevskiy, Mikhail; Dillon, Matthew; Stephani, Eva; O’Donnell, Jonathan (Alaska University Transportation Center, Alaska Department of Transportation and Public Facilities, 2010)
    • Gis-Based Approaches To Slope Stability Analysis And Earthquake -Induced Landslide Hazard Zonation

      Luo, Huayang; Zhou, Wendy (2006)
      This dissertation presents newly developed GIS-based deterministic and probabilistic approaches for slope stability analysis and earthquake-induced landslide hazard zonation. The described approaches combine numerical slope stability analysis with GIS spatial analysis to evaluate earthquake-induced slope failures, both shallow and deep-seated. The study has four major research components. The first component is a GIS-based procedure which was developed based on one-, two-, and three-dimensional (1D, 2D, and 3D) deterministic approaches to slope stability analysis and landslide hazard zonation. Slope stability methods in the GIS-based procedure included the infinite slope model, the block sliding model, the ordinary method of slices, the Bishop simplified method, and the Hovland's column method. The second component focuses on causative factors analysis of earthquake-induced landslide hazards. This component also discusses the determination of peak ground acceleration for slope stability analysis. The third component consists of an evaluation of the topographic effect of ground motion and the seismic response in the Balsamo Ridge area in Nueva San Salvador. The fourth component is concerned with the regional and site-specific landslide hazard zonation, using newly developed models for landslide hazard assessment in Nueva San Salvador. The slope stability and landslide susceptibility were mapped in terms of slope stability index (factor of safety, critical acceleration, Newmark displacement, failure probability, and reliability index). The landslides triggered by an earthquake on January 13, 2001 in El Salvador provide a setting for the calibration of results from GIS-based approaches. The procedures developed in this research proved to be feasible and cost-effective for slope stability analysis and earthquake-induced landslide hazard zonation.
    • Glacial Processes and Their Relationship to Streamflow Flute Glacier, Alaska

      Long, William E. (University of Alaska, Institute of Water Resources, 1972-01)
      Flute Glacier is located at the head of the South Fork of Eagle River, Alaska, about twenty air-miles east northeast of Anchorage. It is a small north-facing glacier, approximately two miles long and half a mile wide, situated in a deep glacial valley (see Figure 1). Elevations on the glacier range from 3,500 feet at the terminous to 5,800 feet at the top of the accumulation area. Water from Flute Glacier becomes the South Fork of Eagle River, draining about 32 square miles of area compared to a 192 square mile drainage basin for Eagle River. Limited discharge measurements made during October 1968 suggest that the South Fork contributes about 20% of the water flowing down Eagle River. Glacial meltwater forms an important percentage of the waters of the Eagle River system. Glaciers feeding the main Eagle River are large, complex and difficult to study. Flute Glacier, relatively small and of simple plan, was selected for study because of its small size and proximity to the metropolitan area of Anchorage. Water from the Eagle River system is presently included in the plans for future water supply for Anchorage. The Eagle River valley up to the 500 ft contour is a federal power reserve. The climate of the area surrounding Flute Glacier is alpine with cool temperatures and higher than average precipitation for the area. All the glacier is above treeline so no plant life is obvious. Mountain sheep inhabit the sharp alpine peaks surrounding the glacier.
    • Go artificial intelligence: a scalable evolutionary approach

      Fraser, Warren Duncan; Hay, Brian; Lawlor, Orion; Genetti, Jon (2016-05)
      This report covers scaling neural networks for training Go artificial intelligence. The Go board is broken up into subsections, allowing for each subsection to be calculated independently, and then factored into an overall board evaluation. This modular approach allows for subsection networks to be translated to larger board evaluations, retaining knowledge gained. The methodology covered shows promise for significant reduction in training times required for unsupervised training of Go AI. A brief history of artificial neural networks and an overview of Go and the specific rules that were used in this project are presented. Experiment design and results are presented, showing a promising proof of concept for reducing training time required for evolutionary Go AI. The codebase for the project is Apache 2.0 licensed and is available on GitHub.
    • Ground penetrating radar forward and backward modeling for layered snow

      Wang, Wei (2007-08)
      Forward and Backward Ground Penetrating Radar (GPR) modeling can provide the information that is useful for geometric and electromagnetic interpretation of layered materials. Given the depth and dielectric constant of snow, one can simulate the GPR signal. This is called forward modeling. On the other hand, given the GPR signal, the determination of depth and dielectric constant is called backward modeling. In this thesis, we briefly discuss a computational GPR forward modeling approach, based on two pieces of software with different principles. The software GPRMAX is able to model snow layers with the Finite Difference Time Domain method; this method is able to distinguish and resolve two consecutive layers with less thickness ([delta]d = 10cm). The software MATHCAD can be utilized to obtain modeling and imaging result using Transmission Line theory; this method is able to distinguish and resolve two consecutive layers with relative small difference in dielectric constant ([lamda epsilon] = 0.01). Then the comparisons of GPR system outputs and modeling techniques give an evaluation of the working performance of the Ground Penetrating Radar system. Secondly, for backward modeling, we used the layer stripping method on the field data as well as forward modeling results. Furthermore, the relative permittivity can be evaluated by the inverse process of transmission line theory with transmission line forward modeling results.
    • Ground Water Quality Effects on Domestic Water Utilization

      Smith, Daniel W.; Casper, Lawrence A. (University of Alaska, Institute of Water Resources, 1974-03)
    • A Ground Water Quality Summary for Alaska: a Termination Report

      Kim, Steve W.; Johnson, Phillip R.; Murphy, R. Sage (University of Alaska, Institute of Water Resources, 1969)
      The expanding economic activity throughout the State of Alaska has created an urgent demand for water resource data. Ground water quality information is of particular interest since this is the most used source for domestic and industrial supplies. Many agencies and individuals have accumulated large quantities of data but their value has been marginal due to a lack of distribution to potential users. It was the original intent of the work reported herein to gather, collate, and publish all ground water quality data available in the files of university, state, and federal laboratories. Soon after the inception of the project the major contributor, the U.S. Geological Survey, found it was administratively impossible to contribute either the monies or the data necessary to accomplish the ultimate goals of the project -- An Atlas on Alaskan Ground Water Qualities. At the time the above decision was made the Institute felt too much information was on hand to allow it to lay fallow. Therefore, this report was prepared, In a more limited scope than originally planned, to fill the need for a readily available source of information.
    • Ground Water: Alaska's Hidden Resource: Proceedings

      Ashton, William S. (University of Alaska, Institute of Water Resources, 1989-03)
      Surface water quality -- Surface/ground water interactions -- Ground water monitoring, modeling, and data management -- Transport and removal of contaminants in soil and ground water
    • Ground-water capture-zone delineation: method comparison in synthetic case studies and a field example on Fort Wainwright, Alaska

      Ahern, Julie Anne (2005-05)
      Ground-water capture zone delineation is an integral part of the recent Source Water Assessments performed nation-wide. Delineations are used to identify where protection from contamination is critical. The objectives of our study were to compare commonly-used methods by quantifying the differences in capture-zone areas and evaluating whether the differences increase with system complexity. We delineated capture zones of hypothetical case studies. We began with a very simple hydrogeologic system and gradually added complexity. Four methods were applied to each case: Calculated fixed-radius (CFR), two analytical solutions (WHPA and UFE-Thiem), and a numerical model (MODFLOW). Area comparisons revealed that, in comparison to the numerical model, CFR consistently overestimated, WHP A underestimated, and UFE- Thiem was variable and the most similar. We then compared the methods in a field case on Fort Wainwright, Alaska. As our numerical method, we used a sub-regional ground-water flow model. Area comparisons were similar to case-study results. Surface-water features were the most influential complexity in the field case. We concluded that each method is only as accurate as its assumptions. Any added margin of error must be appropriate for both the aquifer complexities and required assumptions specific to a given ground-water system.
    • Groundwater dynamics in degrading, discontinuous permafrost

      Barnes, Michelle L.; Barnes, David L.; Shur, Yuri L.; Schnabel, William E.; Leigh, Mary Beth (2014-12)
      In regions impacted by permafrost, discontinuities are areas of possible connection between the supra- and sub-permafrost portions of an aquifer. Permafrost discontinuities influence the transport of contaminants in an aquifer, necessitating delineation of these discontinuities and their influence on groundwater flow. Means of identifying the locations of permafrost discontinuities have previously been limited to geophysical methods and the evaluation of well logs. In this study we use groundwater elevation trends and environmental tracers (e.g., stable isotopes and temperature) to evaluate the dynamics in a sulfolane-contaminated aquifer located in a region of discontinuous permafrost in the Interior of Alaska. Using tracers to identify areas of discontinuities in the permafrost should help us locate thawed through-taliks and may also improve our understanding of the interaction between the supra- and sub-permafrost groundwater in discontinuous permafrost. With this approach we identified at least three discontinuities within the study area. The locations of these discontinuities coincide with transport of the contaminant found in this aquifer. The primary source of recharge for this aquifer is the Tanana River, a major tributary to the Yukon River. The source of water for the Tanana River is glacial melt in the summer and groundwater during the winter. Through the isotopic composition of the supra-permafrost groundwater we show the occurrence of additional recharge to the supra-permafrost groundwater from sub-permafrost groundwater and precipitation. Understanding these dynamics is paramount to characterizing the contaminant transport in permafrost impacted aquifers.
    • Groundwater flow in a vertical plane at the interface of permafrost

      Paturi, Sairavichand; Barnes, David L.; Leigh, Mary Beth; Shur, Yuri (2017-08)
      Groundwater dynamics in discontinuous permafrost aquifers are complex. The topography of permafrost redirects flow in difficult-to-predict directions that can be tens of degrees off from the regional flow direction. Large zones of permafrost vertically separate aquifers into supra and sub-permafrost portions. The flow dynamics in each portion of the aquifer may be dissimilar due to different controlling boundary conditions. In areas of discontinuities in permafrost, known as open taliks, groundwater in the two portions of the aquifer may mix. These areas of mixing are the focus of this study, in particular, the groundwater dynamics in taliks located in the floodplain of lower reaches of rivers. The study hypothesizes that groundwater flow in floodplain taliks of lower reaches of rivers will bifurcate between the supra and sub-permafrost portions of a discontinuous permafrost aquifer. To test this hypothesis gradient, magnitudes and flow directions were determined at several depths ranging from the water table to 150 ft. (45.7 m) below ground surface, using a linear interpolation scheme in various locations in a floodplain talik. Errors in water level measurements due to instrument errors as well as vertically moving wells were propagated into the gradient calculations by Monte Carlo analysis. Results from this research show that a vertical divide in groundwater flow forms a short distance below the top of permafrost. Groundwater flow above the divide routes into the unconfined supra-permafrost portion of the aquifer. Water below the divide flows into the confined portion of the aquifer below permafrost. The position of the vertical groundwater divide may adjust in relation to the water table position. Additionally, a methodology is presented for stochastically propagating measurement errors into gradient analyses by Monte Carlo analysis. Understanding the flow dynamics in discontinuous permafrost aquifers is key to the understanding of contaminant transport, aquifer recharge, and resource development in subarctic environments.
    • Guidelines for the Use of Synthetic Fluid Dust Control Palliatives on Unpaved Roads

      Barnes, David; Connor, Billy (Center for Environmentally Sustainable Transportation in Cold Climates, 2017-07-06)
      The amount of small soil particles, dust, lost from typical unpaved roads to fugitive dust is staggering. A 1 km stretch of unpaved road can contribute over 2400 kg of dust to the atmosphere (4.2 ton/mile) in a typical 3-month summer season. Road managers typically manage dust from unpaved roads with various dust-control palliatives, which are effective for up to 1 year. Synthetic fluids are a relatively new category of dust-control palliatives. Unlike the more commonly used dust-control palliatives, such as salts, engineering guidelines do not exist for the application and maintenance of synthetic fluids on unpaved roads. To fill this void, we present through this document guidelines for road design and maintenance, palliative selection, application, and care of synthetic fluid-treated roadways.