• A study of increased instructional time and the relationship with the mathematical achievement of intermediate elementary students

      Lower, Elizabeth Anne (2005-08)
      The purpose of this study was to determine whether two different approaches to increased instructional time led to a statistically significant increase in math achievement of fifth grade students. The null hypothesis stated that there would not be a statistically significant difference at the .05 level of significance between the math scores of the fifth grade students at schools A and B, as measured by standardized test scores. Data consisted of standardized test scores of annual statewide assessments. The test results were collected and analyzed using SPSS software. The null hypothesis could not be rejected. The results indicated that the largest gains were made by the lowest achieving students. Additionally, in both schools, the students who had scored in the highest quartile on the pre-test were not able to maintain their quartile ranking, and slipped into lower quartile rankings after the different time treatments were applied.
    • A study of near-surface currents in Endicott Arm

      Gleason, Robert R. (1972-05)
      Currents in Endicott Arm were measured by parachute drogues and ice drift photogrammetry. The parachute drogues showed mean outflow speeds between 2 and 20 cm/sec. The mean outflow extended at reduce speeds to below ten meters and may have extended to Bill depth at twenty meters. From equations of drag and inertia, a differential equation was formed to describe tidal ice drift speeds. The equation was solved on an Analog computer and the solution shown as plotted. Coupling curves were used to measure the net tidal speed. Ice drift mean out flow speeds based upon these computations agreed with parachute drogue mean outflow speeds.
    • A Study of overpressure in the Navarin Basin, Alaska

      Robison, Matthew; Atashbari, Vahid; Ahmadi, Mohabbat; Awoleke, Obadare (2019-12)
      The Navarin basin is a region to the west of Alaska between the Aleutian Islands and Russia. It has been identified as a potential Petroleum prospect, and exploration wells have been drilled under the ocean up to depths of 17,000 feet. The exploration of the basin was started by Russia and the United States with several exploratory wells drilled in the 1980’s. The geology of the region consists of tertiary sedimentary rock deposited during the Eocene age with mudstone and siltstone from Paleogenic deposition. When dealing with such depths, it is expected that the pressure will increase beyond the hydrostatic gradient. Overpressure, when unexpected, can cause blowouts or oil spills as well as danger to the oil production workforce. Herein, the origin of overpressure in this basin is examined using the well log and geological information, and potential mechanisms responsible for generating abnormal pressure are further discussed. In this study, extensive existing well log data are thoroughly examined and organized to facilitate the characterization of overpressure zones in the basin. As a preliminary step, well logs from eight exploratory wells in the Navarin Basin were digitized and organized as the basis of the analysis. Next, overburden pressure is determined for each applicable well in the target area by examining well log and other geological information. Then, a shale discrimination scheme is applied on the log data to differentiate clay-rich formations (that undergo mechanical compaction) from other rock types. Overpressure horizons are identified and examined through velocity, resistivity and other well logging measurements of clay-rich deposits. As such, sonic velocity vs. density and resistivity vs. density cross plots are constructed to identify signatures of different mechanisms of overpressure. Further characterization of the origin of overpressure involves examination of the tectonics, stratigraphy and source rock in order to characterize the pore pressure regime. Finally, pore pressure is calculated using Eaton (1974) and Bowers (1995) method are utilized to calculate pore pressure within the studied wells and degree of confidence in such calculations are examined.
    • Study of rheology of gas-to-liquid products, Alaska North Slope crude oil and their blends for transportation through the Trans Alaska Pipeline System

      Inamdar, Abhijeet Ashok (2004-08)
      In order to bring remote natural gas to market, conversion of natural gas to a liquid form (Gas-to-liquids (GTL)) may be an alternative to utilize this gas. Alaskan North Slope might prove as one of the first sites in the USA to commercialize this technology because of the huge natural gas resources it holds. The Trans Alaska Pipeline System (TAPS) will be the means of transportation of this GTL to the market. Thus it becomes major task to evaluate the technical and economic feasibility of transporting GTL products through the TAPS. One of the modes of transporting GTL products from ANS to Valdez is commingling them with Crude oil as a single phase before pumping through TAPS. This changes the properties of GTL as well as the Crude oil. Thus it becomes important to study the physical and chemical properties of not only the GTL but also its blends with the crude oil. Four blends of GTL/crude in the ratios of 1:1, 1:2, 1:3 and 1:4 were prepared for their rheological evaluation at different temperature conditions. Results show that flow behavior of the pure and GTL blends are temperature sensitive. Viscosity and density of the blends decrease with increasing amount of GTL and increasing temperature. Optimum blend ratio is between 1:2 and 1:3 GTL/Crude oil blends.
    • A study of saturation number

      Burr, Erika; Faudree, Jill; Williams, Gordon; Berman-Williams, Leah (2017-08)
      This paper seeks to provide complete proofs in modern notation of (early) key saturation number results and give some new results concerning the semi-saturation number. We highlight relevant results from extremal theory and present the saturation number for the complete graph Kk; and the star K₁,t, elaborating on the proofs provided in the 1964 paper A Problem in Graph Theory by Erdos, Hajnal and Moon and the 1986 paper Saturated Graphs with Minimal Number of Edges by Kászonyi and Tuza. We discuss the proof of a general bound on the saturation number for a family of target graphs provided by Kászonyi and Tuza. A discussion of related results showing that the complete graph has the maximum saturation number among target graphs of the same order and that the star has the maximum saturation number among target trees of the same order is included. Before presenting our result concerning the semi-saturation number for the path Pk; we discuss the structure of some Pk-saturated trees of large order as well as the saturation number of Pk with respect to host graphs of large order.
    • A study of soil topo-sequences in the Steese and White Mountains of Alaska

      Geisler, Eric S.; Ping, Chien-Lu; Juday, Glen; Swanson, David (2018-08)
      The Steese Mountains of Alaska present a complex landscape on which to study soil formation and characteristics in relation to topographic position. The White and Steese Mountains of Alaska are located approximately 70 to 220 km northeast of Fairbanks. Ten toposequences with 3 or 4 sites each were described in the field, sampled, and analyzed in the laboratory in order to determine the relationship between soil morphology and soil-forming factors. Permafrost is discontinuous within the study area and vegetation ranges from tundra on summits to boreal stands of resin birch, quaking aspen, black spruce and white spruce along the lower elevations. There have been many wildfires over time that may have altered the soils and affected the vegetation successional patterns. The processes through which various soil patterns have formed and the unique characteristics of the soils are described here based on field data obtained from both burned and unburned sites. The analysis includes biophysical settings, parent material, texture and nutrient concentrations. Organic horizons were common on most of the transects and play a key role in the depth of the active layer where they exist. Nutrient concentrations are also closely tied to the presence and depth of the organic horizons. Some patterns described in other areas of the boreal region were not observed in this study. There were some soil properties that are not readily described under the current taxonomy protocols which are suggested to be added in a future revision of Soil Taxonomy.
    • Study of solid deposition phenomena and fluid properties of Alaska North Slope crude oil, gas-to-liquid products and their blends for transportation through the trans-Alaska pipeline system

      Ijeomah, Cajetan Eneberi (2005-05)
      Earlier studies on the options for utilization of Alaska North Slope (ANS) gas had indicated that it is economical to convert the gas to Gas-to-Liquid (GTL) products, blend it with the ANS crude oil and transport the resulting liquid through the existing Trans-Alaska Pipeline System (TAPS) to monetize the stranded gas. The objective of this study was to evaluate the effect of blending ANS crude oil with a GTL sample acquired from BP Alaska Inc. (BPGTL). Solid deposition phenomena and fluid properties of ANS crude oil, BPGTL and their blends were studied. The blends of BPGTL and ANS crude oil would require less pumping pressure. It is concluded from this study that the possibility of vapor and wax formation is precluded during transportation of the blends, and that asphaltene deposition is a potential major problem in blending ANS crude oil with BPGTL.
    • Study of the performance of a proton exchange membrane fuel cell

      Morgan, Christopher Lee (2000-08)
      As fossil fuels become scarce, finding new sources of efficient, reliable, and renewable power generation is critical. One device being given lots of attention for this purpose is a fuel cell. Fuel cells not only produce electricity, but also heat which can be recovered for residential use and increase the overall system efficiency. Test benches were constructed to measure and record data from fuel cells under a range of electrical loads. Energy balance was constructed to characterize the fuel cell system using experimental data. The energy balance resulted in a first law gross electrical efficiency of over 44 percent and a second law efficiency greater than 52 percent for the opening range of the fuel cell system.
    • A study of waterflood sweep efficiency in a complex viscous oil reservoir

      Jensen, Marc Daniel; Khataniar, Santanu; Dandekar, Abhijit; Patil, Shirish (2014-12)
      West Sak is a multi-billion barrel viscous oil accumulation on the North Slope of Alaska. The unique geologic complexities and fluid properties of the West Sak reservoir make understanding ultimate sweep efficiency under waterflood a challenge. This project uses uncertainty modeling to evaluate the ultimate sweep efficiency in the West Sak reservoir and honors a rich dataset gathered from 30 years of development history. A sector model encompassing the area of the West Sak commercial pilot was developed and a sensitivity analysis conducted to determine the most important parameters affecting sweep efficiency. As part of this process unique constraints were incorporated into the model including measured saturations at the end of history, and observed completion performance. The workflow for this project was documented and can be adapted for use in larger scale models. The workflow includes the development of static cell properties which accurately represent field behavior, a preliminary history match using conventional methods and a sensitivity analysis employing a multi-run visualization tool to effectively navigate and process large amounts of data. The main contributions of this work include the identification of key parameters affecting sweep efficiency in the West Sak oil field, a documented workflow, and increased insight into observed production behavior.
    • Studying auroral microphysics using multiple optically tracked rocket sub-payloads

      Vann, Joshua M.; Conde, Mark; Delamere, Peter; Hampton, Donald (2018-12)
      There is insufficient knowledge of scale length parameters associated with ionospheric plasma structures. Using a novel technique combining rocket-based instrument data with ground-based optical and instrumental data measurements, ISINGLASS attempts to determine the spatial scale lengths over which parameter differences in auroral arcs present in the upper ionosphere. Determination of such scale lengths has the propensity to strengthen preexisting models of magnetosphere-ionosphere interactions. While analysis is not complete and the extent of such scale lengths is still unknown, after completion of the experiment phase of the mission, differences in measurements have been found that cannot be accounted for through experimental error. This shows the existence of a critical scale length within the distances measured, and the techniques used present a reliable method with which to launch a future campaign.
    • The subglacial hydraulics of the surge-type Black Rapids Glacier, Alaska: a schematic model

      Cochran, Oakley D.; Harrison, William; Weeks, Wilford; Kane, Douglas; Echelmeyer, Keith; Benson, Carl (1995-12)
      The subglacial hydraulic system of the surge-type Black Rapids Glacier was studied in 1993 by comparing glacier velocity and seismicity with the stage, electrical conductivity, and turbidity of its proglacial streams. Brief events of increased velocity and seismicity occurred at the beginning and end of the measurement season. Five events coincided with drainages of supraglacial lakes and potholes. During events, water was stored englacially or subglacially and released subsequently, as indicated by a dye tracing experiment. Conductivity-stage-seismicity relationships suggest a model wherein daily storage and release of water depended on variations in subglacial pressure, which were reflected by daily variations in seismicity. Heavy precipitation and increases in stage preceded late-season pothole drainages. We hypothesize that precipitation triggered pothole drainages by enlarging drainage conduits, thus lowering subglacial pressure. Differences between the drainage systems in 1993 and 1986-89 may reflect mechanisms of surge evolution.
    • Subsistence and commercial fisheries through the lenses of culture and economy in three coastal Alaskan communities

      Holen, Davin L.; Schweitzer, Peter; Carothers, Courtney; Koester, David; Morrow, Phyllis; Shannon, Kerrie-Ann (2017-05)
      Commercial and subsistence fisheries in Alaska are complex social-ecological systems constituting interdependent components which include economics and culture at the local and regional levels. Each fishery has unique challenges and benefits; however, a commonality that can be found in coastal communities in Alaska is that salmon fisheries are for many a way of life that serve to link commercial and subsistence practices to family and traditions. This research investigated whether and how culture is a key component of subsistence and commercial fisheries in three core study communities in different parts of coastal Alaska; Chenega Bay in Prince William Sound, Kokhanok in Bristol Bay, and Tyonek in Cook Inlet, and includes summary research findings from 12 comparative communities on the south side of the Alaska Peninsula, Kodiak Island, and Southeast Alaska. The research sought to understand 1) how people in different areas of Alaska articulate the role of subsistence fisheries in their communities, 2) what factors are impacting participation in commercial fisheries, and 3) what methods could be used to assess the resilience and vulnerability of such diverse coastal communities in Alaska. Among the factors investigated in each community were the role of local level politics and how local knowledge is passed down through participation in subsistence salmon fishing activities. To examine methodologies for assessing community vulnerability and resilience within a larger system, quantitative data gathered through household surveys was used to provide a basic statistical assessment of the economic and subsistence landscape of coastal communities in Alaska. But it was through in-depth semistructured interviews, during which residents shared their own personal stories, that a broader, more accurate assessment of resilience and the complexity of community-based fisheries was achieved. During household harvest surveys administered in the core study and comparative communities, as well as through in-depth interviews conducted in the three core communities, residents articulated how participating in salmon fishing is an expression of a subsistence way of life and of cultural traditions. Commercial fishing as a way of life is also something they seek to pass on to their children. In all of the study communities, residents noted that the reasons they continue to live in their rural coastal communities include family, culture, home, a subsistence lifestyle, and a sense of freedom. Challenges to maintaining continuity in the commercial fishery, and to passing on this lifestyle to their children, include the price effects of the globalization of salmon markets, market access to sell one's fish, and financial difficulties of entering a capital-intensive fishery. However, there are and have been efforts in each of the three communities to revitalize participation in commercial fishing. Residents of these fishery dependent communities have a strong connection to salmon as an economically valuable resource through commercial fishing, and to salmon as a cultural and place-based resource by participating in subsistence salmon fishing.
    • Subsurface structure of the volcanoes in Katmai National Park, Alaska

      Jolly, Arthur D.; McNutt, Steve; Wyss, Max; Eichelberger, John; Stone, David (2000)
      The three-dimensional velocity, attenuation and b-value structure is mapped beneath the Katmai group volcanoes, located in south-central Alaska. Data for these studies include 4320 earthquakes recorded in the period July 26, 1995 to November 30, 1999 on a 5--18 station short-period seismograph array. The velocity structure is determined by inversion of P-wave travel-times for 8041 rays from 815 earthquakes. The inversion revealed the lowest velocities (3.6--5.0 km/s) centered beneath Novarupta, Trident and Mageik volcanoes between the surface and 4 km below sea level and moderately lower velocities at 0--6 km depth between Martin volcano and Katmai caldera (4.5--6.0 km/s). Higher relative velocities (5.0--6.5 km/s) prevail outboard of the volcanic axis and at Griggs volcano. The attenuation structure is determined by inversion of the amplitude spectra roll off to obtain t* for 1301 rays from 230 earthquakes in the magnitude range (0.8 < ML < 1.8). The inversion, which is well constrained in the depth range 0--6 km, reveals higher attenuation along the volcanic axis 1/Q = 0.008-0.018 (55 < Q < 125) and lower attenuation in non-volcanic regions of the study area 1/Q = 0.01--0.000 (100 < Q < infinity). The attenuation is greatest beneath Mageik, Trident and Novarupta (1/Q = 0.018; Q = 55) between the surface and 6 km below sea level. Frequency-magnitude distributions are determined by mapping b-values for ~1300 earthquakes larger than the magnitude of completeness (0.7 ML). The analysis reveals high b -values at Mageik volcano (1.2--2.2), intermediate b-values at Martin (1.0--1.6) and Katmai caldera (1.2--1.4) and low b-values at Trident (0.6--1.2). Results point to the existence of a large region of partially molten rock centered beneath Mageik, Novarupta and Trident volcanoes at 0--4 km depth. The localized nature of the high b-value zone at Mageik volcano suggests that the magma is discontinuous, occurring as several distinct bodies. The deeper high attenuation anomaly might mark the now solidified but highly fractured plumbing system associated with the 1912 Novarupta eruption.
    • Successful Aging Through The Eyes Of Alaska Native Elders: What It Means To Be An Elder In Bristol Bay, Alaska

      Lewis, Jordan Paul (2009)
      Alaska Natives view aging from a holistic perspective, an approach not typically found in the existing literature on successful aging. There is little research on Alaska Native (AN) Elders and how they subjectively define a successful older age. The lack of a culturally specific definition often results in the use of a generic definition that portrays AN Elders as aging less successfully than their non-Native counterparts. This research explores the concept of successful aging from an AN perspective and what it means to age well in AN communities. An Explanatory Model (EM) approach was used and adapted to focus on the health and well-being of AN Elders and to gain a sense of their beliefs about aging. Qualitative, in-depth interviews were conducted with 26 Elders in six participating communities to explore the concept of successful aging and the role of their community in the aging process. Focus groups were held in specific communities to present the findings and receive feedback; this ensured the findings and report would be reflective of the unique perspectives of the communities and region. This study highlights four domains of successful aging, or "Eldership": emotion, spirituality, community engagement, and physical health. One aspect of successful aging seen in each of these four domains is optimism, or having a positive outlook on life. These four domains serve as the foundation of how communities define who is an Elder and what is important when considering whether someone has aged successfully or not. Research findings also indicate that aging successfully is based on local understandings about personal responsibility and making the conscious decision to live a clean and healthy life. Most Elders stated that Elder status is not determined by reaching a certain age (e.g., 65 years), but instead is designated when an individual has demonstrated wisdom because of the experiences he or she has gained throughout life. This research seeks to inform future studies on rural aging that will prioritize the perspectives of Elders to impact positively on the delivery of health care services and programs in rural Alaska.
    • Successional changes in the hydrology, water quality, primary production, and growth of juvenile Arctic grayling of blocked Tanana River sloughs, Alaska

      Wuttig, Klaus G. (1997-08)
      A comparative stream study was conducted to assess the influence of development and blockage on the hydrology, water quality, primary production, and Arctic grayling of Badger Slough, Alaska. Data collected showed that Badger Slough exhibited stable, clear flows throughout the summer, and higher total and total dissolved phosphorus, orthophosphate, alkalinity, pH, conductivity, and average temperatures, and lower winter dissolved oxygen concentrations than both Piledriver and 23-Mile Sloughs. Mean algal biomass (3.3 mg m-3) and primary production (6.9 g O2 m-2 d-1) are greater than that recorded for any other interior Alaska streams and percent fines in riffle substrates have increased. However, growth of age-0 grayling remains high. Badger Slough has eutrophied due to increased nutrients and stable flows, and the quality of rearing habitat for age-0 fish remains good. However, an annual flushing flow of 8.0 m3 s-1 is recommended for controlling accumulations of fines and maintenance of grayling habitat.
    • Suffering, Pity, and Pride: Complexities of the Russian-American adoption relationship from the early 1990's to 2007

      Neighbors, Andrea K.; Schweitzer, Peter; Gray, Patty A.; Koester, David (2008-12)
      This thesis describes and analyzes the Russian-American adoption relationship between the early 1990s and 2007. In the early 1990s, an Non-Governmental Organization report depicting Russian orphanages provided Americans with pitiful images of Russian orphaned children. The report became iconic and shaped the way Americans perceived Russian orphans and orphanages. For the rest of the 1990s, Russian children became one of the most popular adoption choices for American parents; these children had the “right” race and could be “saved”. In 2005, news started to surface that adopted Russian children had been murdered in the U.S. by American adoptive parents. The Russian government responded to this news by placing a moratorium on all foreign adoptions. American adoption practices have, in many ways, hurt the pride of Russians. The perceptions Americans have of Russia as a “third world” country, and the perceptions Russians have of Americans as “greedy Westerners”, influenced the dynamics of this intercountry adoption relationship over the course of fifteen years. In 2007 the ban was lifted, but the relationship had changed significantly due to the shifting priorities of American adoptive parents and the dynamics of U.S.- Russian international relations.
    • Sugpiaq Russian Orthodoxy---Conceptual Analogy In Religious Syncretism In Nanwalek Alaska

      Csoba Dehass, Medea (2009)
      Religious conversion is often highly unstable, can be nominal in nature, and may not have lasting effects on converted people and their culture. For the Sugpiaq of Nanwalek, however, Russian Orthodoxy has become "native" (and Native) in the sense that it has been incorporated into everyday Sugpiaq reality, and referred to as such by all in the community. Therefore, examining the unique history and practice of Orthodoxy in Nanwalek provides insight into the process of integration of a foreign religious idea into a new cultural environment. The focus of this dissertation is on contemporary Sugpiaq Russian Orthodoxy, as it is formulated in culture-specific analogies and conceptualized through the process of religious synthesis. In Sugpiaq Russian Orthodoxy, Russian traditions and Russian Orthodoxy are mediated through a Sugpiaq cultural logic to create and re-create a culturally specific religious identity. To better understand the process of internalization, this dissertation explores the interplay between Orthodox and traditional Sugpiaq understandings of power, hierarchy, social status, and authority. By doing so, it offers insight into how people interpret certain aspects of their religion according to their own ontological reality, in order to integrate foreign religious ideas into the local cultural context. Based on Sugpiaq Russian Orthodoxy, I propose a new term, conceptual analogy, which can be used to explore people's thought processes in assigning cultural significance to religious meaning, as well as through cultural dynamics that govern the selection and maintenance of religious affiliations. Although conceptual analogy is not restricted to one particular religious or cultural tradition the analogy that is conceptualized is always culture-specific. Therefore, conceptual analogies can be found in all situations where an ongoing conversation develops through syncretism, which is an inherent aspect of religion, as cultural internalization and re-conceptualization. Conceptualizing Russian Orthodoxy through Sugpiaq understandings of reality and fully integrating it into their community made it possible for people in Nanwalek to maintain their Orthodox faith. Thus, Russian Orthodoxy is no longer a foreign religious concept in Nanwalek, but rather a significant component of Sugpiaq identity.
    • The suitcase project: a journey in multimodal reading of graphic novels with emergent bilingual fourth grade students

      Ashe, Kayla; Siekmann, Sabine; Martelle, Wendy; Patterson, Leslie (2019-05)
      This teacher action research focuses on how three fourth grade students interact and make meaning as they read the graphic novel, Amulet. While reading from the graphic novel, students engaged in the reading as design process to make meaning. These three students are Yup'ik students enrolled in a dual language school. Students interacted with peers and different modalities of meaning as they engaged in the meaning-making process. Data sources include a teacher research journal, audio recordings of readings and discussions, and students' reader response journals. Data analysis followed constructivist grounded theory. As there were various types of data collected and a multimodal text was used, multimodal data analysis was used to interpret the relationship across the various modes used in the study. Three main findings emerged from the data: 1. Vocabulary can be learned through multiple modes. 2. Students used words to mediate meaning socially and in a private manner. 3. Combined visuals and text support meaning making. These findings led to the conclusion that meaning making and research are both multimodal. The findings also reveal how emergent bilingual students were active meaning-makers and could read and respond to a graphic novel successfully. At times, writing prompts were used. While students designed meaning with multimodal texts, the writing prompts constricted their responses to certain topics, such as setting and characters, and did not allow for students to continue designing meaning in their own ways. Students were able to continue designing their own meaning when responding to the text in a natural, multimodal way without prompts constricting thoughts relating to the text.
    • Summer distribution and habitat characteristics of fin whales (Balaenoptera physalus) and humpback whales (Megaptera novaeangliae) off Northeast Kodiak Island, Alaska

      Baraff, Lisa Susan (2006-12)
      Summer distributions of fin (Balaenoptera physalus) and humpback (Megaptera novaeangliae) whales were examined relative to bathymetry, oceanography, and zooplankton composition and density in Marmot and Chiniak Bays (Kodiak Island, AK) during 2002 and 2003. Habitat use and habitat partitioning were assessed using Monte Carlo and randomization tests, logistic regression analyses, and kernel density probability contours of high-use areas. Fin whales associated with deeper, cooler waters near areas of maximum slope and consistently used Marmot Bay. Fin whale spatial-temporal distribution likely coincided with Neocalanus copepod concentrations during early summer and adult euphausiids later in summer. Fin whale associations with Pseudocalanus copepods may relate more to that copepods' prevalence than to relevance as prey. Humpback whale site fidelity and association with shallow waters was evident in 2002, but not in 2003. Variability in humpback whale distribution was likely related to their exploitation of forage fish aggregations and threshold foraging needs. High densities of adult euphausiids may promote spatial overlap and shared resource use by fin and humpback whales. This mesoscale snapshot of a dynamic nearshore marine environment and the whales foraging there is an integral step toward identifying and characterizing important habitats for endangered fin and humpback whales.
    • Summer ecology of the Teshekpuk caribou herd

      Parrett, Lincoln Scott (2007-05)
      The summer range of the Teshekpuk Caribou (Rangifer tarandus granti) Herd is currently undergoing the initial stages of petroleum exploration and development. Pre-development baseline information is necessary to interpret post-development distribution and habitat selection of caribou and to develop mitigation measures. We estimated bi-weekly distributions, diet and habitat selection by caribou during the summers, 2002-2004, based on aerial relocations of 21-49 radio-collared females. Little or no habitat selection was detected when comparing used locations to habitat available within bi-weekly utilization distributions. Habitat selection was much stronger when comparing bi-weekly utilization distributions to the remaining area of summer use. At the latter scale of analysis, there were dynamic temporal patterns in resource selection by caribou. High air temperature was strongly avoided throughout July. Tussock tundra was avoided early in the summer, but selected during August. Wet sedge was selected in June and from late-August through September. Estimates of dietary nitrogen content indicated that high nitrogen concentrations are available only for a short period in early summer, and declined well before forage biomass. Predicted dietary nitrogen concentration appeared to be much lower for the Teshekpuk Caribou Herd than for the Porcupine Caribou Herd. Successful mitigation measures for petroleum development in NPR-A will need to be spatially and temporally tailored to observed dynamic patterns in caribou resource selection. Future work should estimate the performance of caribou (e.g., survival or weight gain) in relation to habitat quality and use in order to confirm the value of selected habitats and to enhance the robustness of mitigation measures.