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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

A proposed inventory method for analyzing the visual resources of Alaska's north slope

Laurizio, Daniel Gerard January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas State University Libraries
2

Determination of marine migratory behavior and its relationship to selected physical traits for least cisco (Coregonus sardinella) of the western Arctic coastal plain, Alaska

Seigle, John C. 19 December 2003 (has links)
With increased resource development on the western Arctic coastal plain of Alaska (especially within the oil extraction industry) it is important to understand the basic life history attributes of whitefish stocks in the region in order to ensure appropriate management. These fish are a crucial part of subsistence harvests for native Alaskans. Multiple forms of the whitefish least cisco (Coregonus sardinella) have been described based on both appearance and life history traits. Two major forms of least cisco have been mentioned in the literature: a larger normal amphidromous form with fork lengths of approximately 420 mm and a dwarf lake resident form with lengths up to 230 mm. However, there is considerable evidence for additional forms and life history strategies of least cisco. I investigated the relationship between migratory behavior and selected physical traits of least cisco in six lakes and one brackish lagoon in the western Arctic coastal plain of Alaska. I used electron microprobe technology to determine the levels of Sr and Ca in the otoliths of 258 least cisco in order to resolve their marine migratory life history. I also investigated the relationship between migratory behavior and the numbers of gill rakers, lateral line scales, anal rays and dorsal rays as well as condition factor. The vast majority of least cisco captured in these sites were normal in form, yet only ~12% of all samples yielded any sign of sea-run behavior. Evidence for migratory behavior was low even for sites within close proximity to brackish waters. Fish exhibiting marine migratory behavior tended to make their first migrations to sea before age three (mean=2.6 years), although fish in one coastal site (Joeb's) averaged over 5 years of age at first marine visit. There was some evidence of higher condition factors for fish with sea-run migratory experience. There were significant differences in lateral line and dorsal ray numbers among sites but none for anal rays or gill rakers. Variability in all of these characters was high, and fish from coastal sites tended to have greater variability than those from inland sites. Only dorsal rays showed significant differences in meristic traits between sea-run and resident least cisco. These results suggest that least cisco exhibit high variability in physical traits. Also, least cisco appear to be flexible in their use of the marine environment, even within similar forms in the same lake. Some of the most basic life history characteristics of least cisco remain uncertain. With increased resource extraction occurring on the western Arctic coastal plain of Alaska, it is important to continue to investigate these and other life history strategies so as to ensure a sustainable fishery for native inhabitants of the region. / Graduation date: 2004
3

Topics in applied microeconomics : time allocation and natural resource use on Alaska's North Slope and market power in the U.S. motor carrier industry

Nebesky, William E. 04 February 1994 (has links)
This paper presents two applications of empirical microeconomics based on choice theoretic optimization principles. The first topic explores the determinants of subsistence time allocation in a utility theoretic model of household production. The second topic examines firm pricing behavior in a deregulated, but concentrated industry setting. The first part of this applied microeconomic analysis estimates the subsistence time versus wage labor time allocations of Alaska's North Slope inhabitants using ordered probit based on a household production model. The explanatory variables measure labor supply, demographic, and cultural influences. The major findings are as follows. First parameter estimates differ statistically and substantially between Inupiat versus non-Inupiat residents, implying that optimal natural resource management decisions may vary with the ethnicity of the resource owners. Second, marital status, age, gender, and participation in generalized gift giving and receiving are important determinants of subsistence time allocations. Third, time spent in wage labor appears to be exogenous to the subsistence time allocation decision, indicating that the time allocation process is recursive. Fourth, we find an inverse relationship between wage labor time and subsistence participation. This means that reductions in wage employment opportunities lead to increased subsistence activity. For the North Slope, this implies that Prudhoe oil depletion will result in an increase in the use of subsistence natural resources. The second part of this study turns from the individual behavior to firm behavior. During the 1980's, researchers have noted a trend towards increased concentration in the general freight, less-than-truckload (LTL) portion of the U.S. motor carrier industry. The purpose of this study is to employ new empirical industrial organization (NEIO) techniques to determine whether the more concentrated post-1980, LTL motor carrier industry is exerting anti-competitive monopoly pricing behavior. The NEIO approach is used to formulate the relationship between market price and marginal cost in what is referred to as the representative firm's 'supply relation.' The firm's supply relation is estimated jointly with the cost function and the factor share equations under the assumption that cross equation disturbance terms are correlated (SUR). An instrumental variables procedure is used to test and control for correlation between output (on the right hand side) and the disturbance terms in the cost and supply equations. The results indicate that the trend toward increased industry concentration does not imply anti-competitive performance in the sense of rising price-cost margins. / Graduation date: 1994
4

Browse Evaluation and Survey Techniques for the Uinta North Slope Moose Herd

Babcock, William H. 01 May 1977 (has links)
A study was conducted on the North Slope of the Uinta Mountains from January, 1972 through June, 1974, to determine the effects of three simulated levels of moose utilization on the crude protein content, phosphorus content, digestibility and vigor of willow plants. A comparison was also made on the crude protein content, phosphorus content and digestibility of current year's versus past years' willow growth. Finally, the validity of direct and indirect population enumeration methods was compared for the possible development of a standardized moose survey technique. Clipping caused a highly significant increase in crude protein and phosphorus content between treatment levels. There was also a highly significant increase in digestibility between years. Plant vigor comparisons were confounded by additional sources of mortality and the effects of environmental variables. A comparison of the nutrient content and digestibility of 1 t o 5 year-old willow growth showed that crude protein content, phosphor us content and digestibility decreased with increasing twig age. Additional factors are discussed which indicate that the carrying capacity of the winter range is larger than previously described. A poor correlation was found be tween direct aerial moose observations and indirect population estimates from pellet-group counts.
5

INVESTIGATION OF GAS HYDRATE-BEARING SANDSTONE RESERVOIRS AT THE "MOUNT ELBERT" STRATIGRAPHIC TEST WELL, MILNE POINT, ALASKA

Boswell, Ray, Hunter, Robert, Collett, Timothy S., Digert, Scott, Hancock, Steve H., Weeks, Micaela, Mount Ebert Science Team 07 1900 (has links)
In February 2007, the U.S. Department of Energy, BP Exploration (Alaska), Inc., and the U.S. Geological Survey conducted an extensive data collection effort at the "Mount Elbert #1" gas hydrates stratigraphic test well on the Alaska North Slope (ANS). The 22-day field program acquired significant gas hydrate-bearing reservoir data, including a full suite of open-hole well logs, over 500 feet of continuous core, and open-hole formation pressure response tests. Hole conditions, and therefore log data quality, were excellent due largely to the use of chilled oilbased drilling fluids. The logging program confirmed the existence of approximately 30 m of gashydrate saturated, fine-grained sand reservoir. Gas hydrate saturations were observed to range from 60% to 75% largely as a function of reservoir quality. Continuous wire-line coring operations (the first conducted on the ANS) achieved 85% recovery through 153 meters of section, providing more than 250 subsamples for analysis. The "Mount Elbert" data collection program culminated with open-hole tests of reservoir flow and pressure responses, as well as gas and water sample collection, using Schlumberger's Modular Formation Dynamics Tester (MDT) wireline tool. Four such tests, ranging from six to twelve hours duration, were conducted. This field program demonstrated the ability to safely and efficiently conduct a research-level openhole data acquisition program in shallow, sub-permafrost sediments. The program also demonstrated the soundness of the program's pre-drill gas hydrate characterization methods and increased confidence in gas hydrate resource assessment methodologies for the ANS.
6

Using Facies Analysis and Reservoir Characterization of the Albian-Cenomanian Nanushuk Formation to Assist in Better Understanding Interactions Between Shoreface, Deltaic, and Fluvial Systems on the North Slope, Alaska

Smoot, Andrea 16 December 2021 (has links)
The Albian-Cenomanian Nanushuk Formation located on the North Slope of Alaska is the result of fluvial, deltaic, and shoreface processes and has been the focus of recent petroleum exploration activity in the Colville Basin. The Nanushuk and underlying Torok formations together contain an estimated 8.7 billion barrels of oil and 25 trillion cubic feet of natural gas reserves within the resource-rich North Slope. The Nanushuk Formation is composed of sediment sourced from the Chukotka Peninsula to the west and deposited axially within the Colville Basin. High sedimentation rates led to rapid progradation of shoreface and deltaic systems, which effectively filled the entire basin during the Cretaceous. Resulting in a thick stratigraphic succession of marginal to deep marine sandstones and mudstones. However, considerable facies variation within the basin has led to a previous lack of understanding of the spatial distribution of depositional elements. Integration of outcrop photogrammetry, detailed measured sections, core interpretations, hand samples, and thin section microscopy from the Colville Basin in this study reveal the distribution of litho- and depo-facies within the Nanushuk Formation. Three key outcrop locales along the northern flank of the Brooks Range expose ~200 to ~1000 feet of mudstone, silty sandstone, and sandstone that record the transition from distal shoreface sedimentation to deltaic and fluvial processes over time. Progradationally-stacked parasequences are clearly identifiable in both outcrop and core, recording rapid axial progradation to the east. While shoreface processes do exist in the Nanushuk, outcrop observations show a dominance of deltaic processes, consistent with the highly progradational nature of the strata. Further, there is a trend towards more fluvially-dominated deltaic processes in the more axial part of the Colville syncline, as shown by core, compared to more wave-dominated deltaic facies associations along the margins of the axial basin where outcrops were described. These trends, both vertically and spatially, have important implications for understanding the geologic evolution of the formation and for targeting areas for further exploration within this evolving hydrocarbon play.
7

Paleoenvironmental analysis of Cretaceous mudstones at Slope Mountain, Alaska using carbon stable isotopes

Ratigan, Ashley 16 June 2016 (has links)
No description available.
8

Physical controls on hydrate saturation distribution in the subsurface

Behseresht, Javad 22 February 2013 (has links)
Many Arctic gas hydrate reservoirs such as those of the Prudhoe Bay and Kuparuk River area on the Alaska North Slope (ANS) are believed originally to be natural gas accumulations converted to hydrate after being placed in the gas hydrate stability zone (GHSZ) in response to ancient climate cooling. A mechanistic model is proposed to predict/explain hydrate saturation distribution in “converted free gas” hydrate reservoirs in sub-permafrost formations in the Arctic. This 1-D model assumes that a gas column accumulates and subsequently is converted to hydrate. The processes considered are the volume change during hydrate formation and consequent fluid phase transport within the column, the descent of the base of gas hydrate stability zone through the column, and sedimentological variations with depth. Crucially, the latter enable disconnection of the gas column during hydrate formation, which leads to substantial variation in hydrate saturation distribution. One form of variation observed in Arctic hydrate reservoirs is that zones of very low hydrate saturations are interspersed abruptly between zones of large hydrate saturations. The model was applied on data from Mount Elbert well, a gas hydrate stratigraphic test well drilled in the Milne Point area of the ANS. The model is consistent with observations from the well log and interpretations of seismic anomalies in the area. The model also predicts that a considerable amount of fluid (of order one pore volume of gaseous and/or aqueous phases) must migrate within or into the gas column during hydrate formation. This work offers the first explanatory model of its kind that addresses "converted free gas reservoirs" from a new angle: the effect of volume change during hydrate formation combined with capillary entry pressure variation versus depth. Mechanisms by which the fluid movement, associated with the hydrate formation, could have occurred are also analyzed. As the base of the GHSZ descends through the sediment, hydrate forms within the GHSZ. The net volume reduction associated with hydrate formation creates a “sink” which drives flow of gaseous and aqueous phases to the hydrate formation zone. Flow driven by saturation gradients plays a key role in creating reservoirs of large hydrate saturations, as observed in Mount Elbert. Viscous-dominated pressure-driven flow of gaseous and aqueous phases cannot explain large hydrate saturations originated from large-saturation gas accumulations. The mode of hydrate formation for a wide range of rate of hydrate formation, rate of descent of the BGHSZ and host sediments characteristics are analyzed and characterized based on dimensionless groups. The proposed transport model is also consistent with field data from hydrate-bearing sand units in Mount Elbert well. Results show that not only the petrophysical properties of the host sediment but also the rate of hydrate formation and the rate of temperature cooling at the surface contribute greatly to the final hydrate saturation profiles. / text
9

Post-Den Emergence Behavior and Den Detection of Polar Bears (<em>Ursus maritimus</em>) in Northern Alaska and the Southern Beaufort Sea

Robinson, Rusty Wade 01 March 2014 (has links) (PDF)
Pregnant polar bears (Ursus maritimus) construct maternal dens out of snow in the autumn where they give birth to and raise altricial young. In recent years, there has been a decrease in polar sea ice extent and thickness, which has led to changes in denning behavior. One such change in the southern Beaufort Sea (SBS) is that polar bears are selecting maternal den sites on land, rather than on unstable sea ice. This change, coupled with expanding petroleum exploration along Alaska's North Slope, heightens the likelihood of bear-human interactions at maternal den sites. The purpose of this research was to 1) describe polar bears' post-den emergence behavior, establishing a benchmark for comparison to identify behavioral changes associated with climate change and disturbance, and 2) explore factors influencing the efficacy of a currently used den detection method, forward-looking infrared (FLIR). Maternal den sites were observed along Alaska's North Slope from March to April of 2009 and 2010. The mean length of stay at den sites post-emergence was 11.3 ± 7.5 d. The mean date of den emergence was 14 March; abandonment 26 March. Adult females were generally inactive (58.4% out-of-den time) with standing being the most prevalent activity (49.9%). Cubs were generally active (76.7%), playing more than any other activity (45.3%). Bears spent the majority of their time in the den (97.3% for adult females and 99% for cubs) with short bouts of intermittent activity (× = 7 min 42 s). We documented the death of one member of a triplet polar bear litter at its den site. All three cubs showed low activity levels relative to other cubs observed, and one died within one week of den emergence. Necropsy confirmed that the dead cub had a low body weight and was malnourished. Capture later confirmed that the two surviving cubs were also undersized. Triplet litters are often smaller and suffer higher mortality rates than singletons and twins. This cub was not only a triplet but also born following 2 y of record minimum sea ice extent, both of which may have played a role in this cub's death. Concurrent with the den emergence portion of this work, we conducted a separate study to identify limitations and optimal conditions for locating dens using FLIR. We took handheld FLIR images of three artificial dens under varied conditions. We tested variables hypothesized to influence detectability with linear models using a zero-inflated negative binomial distribution. Solar radiation, wind speed, and den wall thickness reduced the likelihood of detecting dens. The negative effect of wind speed on detectability increased with increasing distance. To maximize the efficacy of hand-held FLIR, den surveys should be conducted when solar radiation is <16 w/m2 (night) and when wind speed is <10 km/h (6 mph). Adherence to these guidelines will maximize the protection FLIR can afford to denning bears.
10

Evolution thermo-cinématique et géodynamique du Brooks Range et du North Slope (Alaska-Canada) / Thermo-kinematic and geodynamical evolution of the Brooks Range and North Slope (Alaska-Canada)

Bigot-Buschendorf, Maelianna 03 December 2015 (has links)
La zone de déformation compressive des Brooks Range et des British-Barn située entre l’Alaska (Etats-Unis) et la région du Nord Yukon (Canada), en position arrière-arc, se développe dans un contexte cinématique et géodynamique depuis longtemps débattu. L’histoire tectonique du bloc continental Arctique d’Alaska, situé dans l’avant-pays de Brooks Range, est diversement interprétée dans les reconstructions de l’ouverture du bassin canadien. La chaîne de Brooks se développe à partir du Crétacé inférieur et sa mise en place se poursuit au Cénozoïque. Mieux contraindre son histoire d’exhumation, en relation avec le raccourcissement est essentiel dans cette région arctique où la cinématique des plaques, associée à l’ouverture du bassin canadien au Nord, fait l'objet de nombreux modèles géodynamiques controversés. La relation avec la subduction active Pacifique au Sud et les grands décrochements en arrière de la subduction fait de cette chaîne, en position arrière arc, une zone-clef pour affiner les reconstructions géodynamiques régionales et notre compréhension des processus orogéniques. Si le lien n'est pas établi entre la déformation mise en jeu dans cette subduction au Mésozoïque et la déformation dans la chaîne de Books, ce lien est en revanche assez bien documenté à l'heure actuelle. Il est donc légitime d'appréhender les événements sud-alaskans dans l'étude de cette chaîne de Brooks. La croissance de la chaîne au Cénozoïque est également mal comprise. Or, il s’agit d’un exemple quasi-unique de chaîne en milieu arctique active durant le Cénozoïque et qui a donc potentiellement enregistré des bouleversements climatiques majeurs, en l'occurrence depuis l‘optimum climatique à la transition Paléocène-Eocène, le refroidissement Oligocène jusqu’à la mise en place de glaciers et de la calotte nord-américaine au Quaternaire. Cet orogène est donc clef pour étudier voire quantifier l'impact du climat sur la construction topographique nord-alaskane. Ce travail a combiné une étude thermochronométrique basse-température multidatation (FT, (U-Th)/He) dans les massifs granitiques et dans les sédiments, qui ont fait l'objet de modélisation thermo-cinématiques via Pecube, dans le but de contraindre la construction orogénique depuis 100 Ma jusqu’à l’actuel. En parallèle, une approche structurale de terrain (Nord Yukon et Brooks Range) et l'analyse de données de subsurface ont été menées. Les données thermochronologiques, couplées à des analyses thermométriques RSCM et de la modélisation thermique soulignent la mise en place de reliefs au Crétacé supérieur avec une exhumation modérée (0.2 km/Ma) qui se poursuit jusqu'à la fin de l'Eocène, où les taux d'exhumation dans les chaînes de Brooks et British-Barn sont clairemement orogéniques (1.25-1.29km/Ma), et associés à la migration de la déformation vers les bassins adjacents. Ce travail souligne une migration de la déformation du SO vers le NE. Dans les deux segments de la chaîne un événement d'exhumation distinct est identifié à l'Oligocène : celui-ci est clairement associé dans la partie interne de la chaîne de Brooks à la mise en place hors-séquence d'un duplex crustal ; et associé à la migration de la déformation compressive en mer au large de la chaîne de British-Barn. Si le calendrier tectonique est semblable dans ces deux zones d'étude, il existe une différence majeure dans le style de déformation entre ces deux régions. Le front de déformation semble beaucoup plus éloigné de la chaîne et les failles beaucoup plus espacées dans la partie canadienne, éloignement et espacement probablement liés à l’épaisseur de sédiments syn-sédimentaires présents dans le bassin... / The kinematics and geodynamics associated with the compressional deformation in the Brooks Range and British-Barn Mountains, respectively in Alaska (USA) and North Yukon (Canada), in a back-arc setting has long been debated. In particular, the tectonic history of the Arctic Alaska continental block located in the foreland of the Brooks Range has been diversely interpreted in the plate reconstructions proposed for the Canadian basin. The Brooks Range mountain chain develops from the Lower Cretaceous to the Cenozoic. Constraining its exhumational history and its link with shortening evolution is essential in this arctic area where plate tectonics, associated to the Canadian basin opening in the North, has led to controversial geodynamic models. Tectonic coupling with the active Pacific subduction in the south as well as major seismogenic strike-slip faulting make this orogen a key area where to refine the regional plate reconstructions and understanding of orogenic processes. The Cenozoic evolution of the Brooks Mountains is poorly understood although it is a nearly unique example of arctic orogen, which have potentially recorded major climate changes like Paleocene-Eocene Thermal Maximum, the Oligocene cooling and Quaternary glaciations. This orogen is a key to study and quantify the climate impact on the north-alaskan topographic growth. This study combined low-temperature thermochronometry (FT, U-Th/He) on granitic and sedimentary rocks, which were thermo-kinematically modeled using Pecube in order to define the orogenic evolution of this arctic region since 100 Ma. In parallel, a field-based structural study (North Yukon and Brooks Range) was combined with the analysis of subsurface data. Thermochronological data, coupled to thermometric RSCM analyses and thermal modeling first define a slow exhumation period (0.2 km/Ma) from Upper Cretaceous up to the Eocene. With the Eocene, exhumation rates drastically increased to reach 1.25-1.29km/Ma as the deformation also migrates from SW toward NE. In both alaskan and canadian parts of mountains ranges a clear Oligocene exhumational event is identified. This event is linked to out-of-sequence crustal duplexing in the internal part of the range in the Brooks Range, contemporaneous with the propagation of deformation offshore, along British and Barn Mountains...

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