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College of Fisheries and Ocean Sciences (CFOS)
The College of Fisheries and Ocean Sciences educates and inspires the next generation of world-class aquatic ecosystem scientists. -
Office of the Provost
The University of Alaska Fairbanks Provost is responsible for providing overall leadership, coordination and direction to UAF research and scholarly activities and graduate studies. -
School of Natural Resources and Agricultural Sciences (SNRAS)
As the primary land-grant component of the university, SNRAS administers a variety of programs and engages in cooperative efforts with federal, state, and borough governments and agencies. -
UAF Graduate School
University of Alaska Fairbanks Graduate School -
Undergraduate Research and Scholarly Activity
At the University of Alaska Fairbanks, the Office of Undergraduate Research and Scholarly Activity (URSA) supports, develops and institutionalizes UAF's diverse and robust programs of undergraduate research and creative ...
Recent Submissions
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Preliminary geothermal investigations at Manley Hot Springs, AlaskaManley Hot Springs is one of several hot springs which form a belt extending from the Seward Peninsula to east-central Alaska. All of the hot springs are low-temperature, water-dominated geothermal systems, having formed as the result of circulation of meteoric water along deep-seated fractures near or within granitic intrusives. Shallow, thermally disturbed ground at Manley Hot Springs constitutes an area of 1.2 km by 0.6 km along the lower slopes of Bean Ridge on the north side of the Tanana Valley. This area includes 32 springs and seeps and one warm (29.1° C) well. The hottest springs range in temperature from 61° to 47° C and are presently utilized for space heating and irrigation. This study was designed to characterize the geothermal system present at Manley Hot Springs and delineate likely sites for geothermal drilling. Several surveys were conducted over a grid system which included shallow ground temperature, helium soil gas, mercury soil and resistivity surveys. In addition, a reconnaissance ground temperature survey and water chemistry sampling program was undertaken. The preliminary results, including some preliminary water chemistry, show that shallow hydrothermal activity can be delineated by many of the surveys. Three localities are targeted as likely geothermal well sites, and a model is proposed for the geothermal system at Manley Hot Springs. Water circulates through biotite granite of the Hot Springs Dome stock and then migrates upward through hornfelsed sedimentary rocks of the informally named “Boulder Ridge Formation.” The springs issue from loess deposits of approximately 5 to 30 meters in thickness. The loess may act as an impermeable caprock allowing thermal water to reach the surface along fractures. The study did not conclusively recognize a controlling fault or fault system at Manley Hot Springs. Some evidence suggests that faults may be present, but they are well-masked by alluvial and vegetative cover. Follow-on studies suggested include more extensive helium surveying, galvanic resistivity and a seismic survey.
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Variables involved in descriptions of world-wide auroral morphologyAny aspect of auroral morphology is a function of three spatial and one temporal variable and therefore is difficult to describe adequately on a two dimensional sheet of paper. Emphasis is given here to examination of the variables and fixed parameters employed in descriptions of auroral morphology.
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Workshop on Alaskan Hydrology : problems related to glacierized basins : final reportThis report summarizes the results of the international Workshop on Alaskan Hydrology: Problems Related to Glacierized Basins, held in Eagle River, Alaska, during April, 1985. Hydrology in Alaska is strongly influenced by problems associated with snow, ice and permafrost which will become increasingly important as economic development proceeds. The Scandinavian countries, Switzerland and Canada have preceded Alaska in developing hydrological resources that depend on glaciers for their sources, and Alaskans can learn from their experience. The international workshop sought to capitalize on this expertise and experience from abroad, and to help bridge the communication gap between scientific and engineering/management groups by having both groups participate. The subjects considered were: runoff from glacierized basins, sediments in glacial streams, hazards associated with glaciers, ice problems on rivers and reservoirs, and selected aspects of permafrost hydrology in glacierized basins. Two days of the workshop were devoted to presentations by the participants, followed by intensive meetings of five subgroups. This report contains the conclusions and recommendations of the subgroups, a list of participants, summaries of presentations, and bibliographic material.
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The June 21, 1967 earthquake series at Fairbanks, Alaska : aftershock locations, depths and magnitudesAftershock recordings have been obtained to determine the extent of the fracture area which using some 50 shocks, was found to be an area of 10 x 15 km with the major axis roughly oriented in a NW-SE direction. Hypocenter depth varies from 6 to 19 km, with most of the shocks being confined to a depth of 10 to 13 km. It was found that the Jeffreys-Bullen velocities, Vp = 5.56 and Vs = 3.37 km/sec, represent a close approximation of the velocities in the area. Presented also are the telemeter network readings from June 21, 1800 GMT to July 14. These readings include the aftershocks of magnitude 2.5 and upward.
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Results of the HF forward and backscatter program at College since 1963This report describes the results of the HF backscatter and forward sounding project conducted at College, Alaska, from 1963 to 1966. The primary finding was that with the exception of slant-F, meteor and groundscatter echoes, the oblique backscatter echoes observed from the auroral zone and polar cap ionospheres were produced by the aurora. When combined with satellite data, this result led to the conclusion that the auroral precipitation markedly increases the electron density at all ionospheric heights, and an auroral model incorporating this notion explains most of the observed details of auroral backscatter, and of auroral sidescatter on forward-oblique paths. The absence of groundscatter from beyond the auroral belt is explained as being due, in part, to the enhanced ionization of the E region by the auroral precipitation. Aspect-sensitive auroral backscatter can be obtained from the south as well as from the north in the northern hemisphere. A single sounder installed at each geomagnetic pole could provide real-time information on the position of the auroral precipitation completely about the pole. Auroral morphology studies made from radio data are independent of the weather and the season. An examination of a year’s data shows that no marked difference exists between the behavior of the summer and winter positions of the auroral precipitation; the northern limit of the south boundary of the aurora during the day was found to be approximately 1.5° geomagnetic latitude north of that during the winter. The radio data for 1965 agrees closely with published optical data for the period of 1957 to 1959 when the level of magnetic activity is considered. This finding shows that the position of the southern boundary of the auroral precipitation for a given level of magnetic activity does not depend appreciably upon the level of solar activity. The excellent correspondence between the optical and radio determinations of the auroral position and occurrence rates is added evidence that the radio method provides reliable auroral tracking information.
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Catalogue of Huet auroral spectra 1957-1963The zenith auroral spectra at College, Alaska, obtained during the six observing seasons from the fall of 1957 through the spring of 1963 have been assembled into catalogue form. The prime purpose of this catalogue is to present the auroral activity in a manner which can be used by others in the interpretation of aurorally associated phenomena. From the general appearance of the spectra and other factors a table of daily activity index number (1-9) is given for each observing period. The monthly averages of these index numbers have been plotted for this entire period and compared with various indices of solar and geomagnetic activity. An anomalous increase in the auroral activity index in the fall of 1962 destroys an otherwise perfect trend in the relation of the auroral activity to the decline in the sunspot cycle. It is suggested that a more detailed investigation of both solar and geomagnetic variations is warranted in order to assess the relative contribution of natural and man-made events in producing this anomalous effect.
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Electrical conductivity, freezing temperature, and salinity relationships for seawater and sodium chloride solutions for the salinity range from 0 to over 200 PPTAlgorithms for the conversion of electrical conductivity to salinity (and vice-versa) for seawater and sodium chloride solutions were developed. Algorithms developed for seawater were based on laboratory measurements of synthetic seawater were based on laboratory measurements of synthetic seawater solutions and are valid for the salinity range from 0 to about 212 ppt at temperatures of 15, 20 and 25°C. Algorithms developed for NaCl solutions were based on literature data and are valid for the salinity range from 0 to about 250 ppt at temperatures of 20 and 25°C. Previous work by others for the conversion of salinity to the freezing temperature for seawater solutions is discussed. From this work, expressions for the conversion of the freezing temperature to salinity were derived and are given for the salinity range from 0 to about 230 ppt. Algorithms for the conversion of salinity to the freezing temperature (and vice-versa) for sodium chloride solutions were developed, based on literature data, for the salinity range from 0 to about 230 ppt.
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Promoting Positive Traffic Safety Culture in RITI Communities through Active Engagement: Implementation Guide and Outreach ActivitiesRural, Indigenous, Tribal, and Isolated (RITI) communities’ crash data analysis clearly highlights three major areas of concern: prevalence of excessive speed, impaired and distracted driving, and underage driving. Safety-focused educational programs and awareness campaigns have all contributed to a reduction in crashes in urban areas. However, in RITI communities, much more work is still needed. It is important that communities are provided with the proper resources and methods to deliver the appropriate training and educational tools that promote and cause a significant positive change in the traffic safety culture. Through reviewed literature and interviews with tribal community stakeholders, this research team came to understand that tribal youth are most impacted and engaged when educational material is made culturally relevant. We then developed an implementation guide to be used by tribes to create, develop, and enact a sustained educational program with the mission to positively impact traffic safety culture among youth in tribal and rural communities.
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Experiment LuxembourgThe radio-wave interaction technique has been applied to the study of the lower ionosphere at College, Alaska. The system employs a pulsed wanted transmitter operating at a frequency of 4.86 Mc/s and a pulsed disturbing transmitter operating at 17.5 Mc/s with an output power of 100 kw. Radio-wave interaction has been recorded over the elevation range from 30 to 70 km. The system is best adapted to observations under somewhat disturbed ionospheric conditions. The observed interaction normally shows significant variation within time intervals of the order of minutes. Some collision frequency and electron density values have been derived. The disturbing transmitter, the 4x4 array of 3-element Yagi antennas, and the receiving circuitry have been adapted to allow the reception of backscatter signals at the disturbing frequency or cosmic noise on an adjacent frequency. Analysis of system performance in the various modes of operation is continuing.
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On the strong influence of the F1 layer on medium to high latitude HF propagationDuring the recent sunspot minimum of the F1 layer critical frequency was close to that of the F2 in the medium to high latitudes. This considerably modified HF propagation conditions over long distance paths. At times the F1 layer appeared to block off the propagation of signals in the very oblique F2 modes. High order F2 mode signals were frequently strong and were reflected from large virtual heights. This retardation was produced by the dense, thick F1 layer which existed in the medium to high latitudes during the summer of 1964. The maximum radio frequency for the path was frequently determined by the F1 layer; although this effect has been noted by various workers, it has not been taken into account for communications predictions. One particularly strong and highly delayed type of signal is not readily explainable as a higher order F2 mode because it occurred singly. If it were an ordinary F2 mode trace, its occurrence would lead to the conclusion that the only F2 layer signal propagating was a third or fourth order mode signal on paths of 3500 to 5000 km, and such a conclusion is hard to justify. As an alternative, an F1-F2 ducted mode hypothesis is presented.
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Interpretation of geophysical well logs in permafrostThis report is a collection of information on the interpretation of well logs and borehole geophysical surveys in permafrost. The body of the report is preceded by an executive summary that gives the highlights of the report in condensed form. The introductory chapter contains background information that is fundamental to the understanding of well log applications in permafrost, including definitions and descriptions of well logs, permafrost, and related terms, and illustrations showing the extent of permafrost in Alaska. Chapter 2 presents information on physical properties of permafrost that relate to well log interpretation, including porosity and pore-filling media (water, ice and air), and their effects on thermal properties, electrical properties and acoustic properties. Chapters 3-8 describe the following types of well logs in detail, including measurement principles and methods, procedures for calibration and interpretation, and identification of special problems related to permafrost: thermal logs, electric logs, sonic logs, nuclear logs, magnetic logs, and miscellaneous (caliper and drilling) logs. Chapter 9 gives information on three types of borehole geophysical surveys, electrical resistivity, seismic velocity, and borehole gravity, with emphasis on the increased depth of investigation afforded by these surveys as compared with well logs. Chapter 10 described a number of specific applications, including the identification of lithology in permafrost, characterization of the thermal regime and the thermal properties of permafrost, petroleum exploration and production, mining applications, and geotechnical applications. A concluding chapter summarizes the information contained in the body of the report and includes a table that gives an overview of the relative value of various borehole geophysical measurements that can be used for delineating and characterizing permafrost. Conclusions of the report are that a number of standard borehole measurement techniques have been tried and proven in permafrost and can be used effectively to delineate and characterize earth material penetrated by the borehole. However, there are several well logging techniques that have special potential for detecting permafrost that have not been tested: dielectric constant, sonic waveform, televiewer, and nuclear magnetic resonance. Borehole electrical and seismic surveys have potential for detecting permafrost at large distances from the borehole, and these techniques need further development and refinement to take full advantage of their capability.
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Tracking the aurora by a multifrequency HF backscatter sounderA comparison of simultaneous optical and radio auroral data obtained during 12 days in December, 1964, shows conclusively that the radio wave scattering belt includes the visual auroral belt. The optical data were obtained with the Alaskan network of all-sky-cameras located between 65 and 80° north geomagnetic latitude. With the exception of vertical incidence, meteor, groundscatter, and slant F (polar spur) traces, all of the recorded backscatter traces from the north were scaled indiscriminately for slant range. The excellent agreement that resulted leads us to conclude that the majority of the HF and low VHF backscatter echoes observed at high latitudes are auroral echoes in the strict sense of the term. In the records shown the auroral belt was tracked from 65 to above 80°N geomagnetic latitude. It is concluded that the multifrequency HF backscatter sounder makes year-round observations of the auroral belt possible.
