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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.
51

Analysis of freight transportation in the Yukon economy

Freybe, Henning Carl Albert January 1968 (has links)
Transportation has always been of vital importance in the Yukon because of the small population, the harsh climate, and the remoteness from large markets. It has imported almost all of its industrial and consumer goods, supported by the export of a limited tonnage of high value mineral concentrates. Little growth has occurred in the past fifteen years in the value of mineral production, as it has remained fairly constantly at about $14 million. At present, though, the Yukon is in a stage of transition as many ore bodies are being brought into production. The effect on the Yukon economy will be substantial, as one estimate sees the dollar value of production increasing more than three-fold by 1975. The objective of this thesis is to determine the impact of this economic change on the total transport system. It is thus necessary to establish a measurement of the present level of freight services (the year chosen is 1964) and to establish a forecast of freight services for 1975. The measurement and forecast are then used to determine in what way the economic change may influence transport rates and services. The main sources of information for this paper were the various transportation and mining companies that are engaged in Yukon activities. Considerable use was made of the 1966 Stanford Research Institute study that concerned itself with the economics of paving the Alaska Highway. While many other sources were also consulted, they were generally of lesser importance. The growth rate of goods going north into the Yukon is forecast to be a moderate 5% per annum. The growth in the amount of ore concentrates going out of the Yukon should be considerably larger. For every ton moving north into the Yukon in 1964, 1.5 tons of freight moved out of the area, while by 1975 the ratio should increase to 6.5 tons for every northbound ton. As the present and planned mining developments are principally in the area north and northeast of Whitehorse where the White Pass and Yukon Route has the competitive advantage, most of the direct increase in freight traffic should benefit the White Pass and Yukon Route. Other transport companies should benefit also, but more due to indirect effects of the mining developments on freight traffic. The increase in the level of freight should make possible a higher utilization of present facilities and lower average costs. It appears that especially for the White Pass and Yukon Route the potential for reductions in freight rates should increase. / Business, Sauder School of / Graduate
52

A geomorphic investigation of retrogressive thaw slumps and active layer slides on Herschel Island, Yukon Territory /

De krom, Valentina January 1990 (has links)
No description available.
53

Mapping permafrost and ground-ice related coastal erosion on Herschel Island, southern Beaufort Sea, Yukon Territory, Canada

Lantuit, Hugues January 2004 (has links)
No description available.
54

The palaeobotany and stratigraphic sequence of the pleistocene Klondike "muck deposits".

Campbell, John Duncan, 1923- January 1952 (has links)
The Klondike District of Central Yukon Territory around Dawson City is particularly advantageous for the study of the sequence of the Pleistocene epoch because it was never glaciated and therefore has never lost its fossiliferous superficial deposits. This paper presents a pollen diagram from a Sphagnum peat bed, which was the youngest deposit discovered, and pollen floras from different ages back to the Pliocene. The peat bed flora shows fairly steady climatic conditions little different from the present; the Pliocene flora shows a distinctly warmer climate; and all the others appear to show colder climates. The paper also presents a theory of correlation of geological events in the district with world-wide climatic variations: cutting of very broad creek valleys; climate warm - Earlier Tertiary - deposition of the oldest gravels; climate warm - Pliocene - deposition of oldest unweathered gravels; climate cold - Nebraskan Glaciation - rapid cutting of narrow lower creek valleys - Three Major Interglacial Ages - major interruptions of valley cutting; climate cold - Kansan and Illinoian Glaciation - deposition of thick valley - bottom muck; climate cold - Wisconsin Glaciation - erosion of valley - bottom muck; climate warmer than the present - Post-Glacial Climatic Optimum - deposition of Sphagnum peat bed; climate same as today - Recent Time [...]
55

Massive ice in coarse-grained sediments, Western Canadian Arctic

De Pascale, Gregory P. January 2005 (has links)
Destruction of ecosystems and infrastructure can be caused by melting of massive ice within permafrost. To predict potential melting caused by natural and human disturbance, we need to know the nature and origin of massive ice deposits. The purpose of this research was to evaluate the nature of massive ice in coarse-grained sediments that accepted theories suggest should not occur. / Degradation of ice-rich granular resources is expensive and difficult to rehabilitate and can cause developmental thermokarst, overestimation of granular resources, disturbance of wildlife habitat and create conflicts with traditional land uses. / To locate massive ice we used a resistivity geophysical technique and to characterize the ice we used geochemical, petrographic and stratigraphic techniques. The resistivity technique detected bodies of massive ice and ice-rich sediments and coarse-grained sediments at high resolutions and laboratory analysis reveal that the ice was of glacial origin. / These findings indicate that massive ice of glacial origin occurs in coarse-grained sediments in permafrost. The techniques used in this study could form the basis of a predictive model of massive ice occurrence.
56

Stratigraphic, structural, and tectonic setting of an Upper Devonian-Mississippian volcanic-sedimentary sequence and association base metal deposits in the Pelly Mountains, southeastern Yukon Territory

Mortensen, James Kenneth January 1979 (has links)
The central Pelly Mountains in southeastern Yukon Territory consist of imbricate thrust sheets, which have undergone syn- and post-thrusting deformation and metamorphism. The local geology is further complicated by intrusion of Upper Cretaceous batholiths, and by strike-slip faulting related to the Tintina Fault, a major northwest-trending transcurrent fault of uppermost Cretaceous or early Tertiary age. This faulting disrupts the northeast edge of the study area. Upper Devonian and Mississippian strata are present in at least two of the thrust sheets, but the Mississippian volcanic rocks occur in only one of them. The volcanic rocks consist of volcaniclastic material with minor interbedded flows, and were deposited in a submarine environment. Several coeval and cogenetic syenite and trachyte domes and small stocks are the remains of vent areas. Although the volcanic rocks are all highly altered and show evidence of widespread chemical mobility, trace element data indicate that the rocks are meta-luminous trachytes, most closely resembling peralkaline volcanics generated in extensional environments. This suggestion of a predominantly extensional tectonic setting in mid-Mississippian time in the Pelly Mountains is consistent with recent tectonic syntheses for the area. Stratabound and stratiform massive base metal sulphide deposits that occur within the Mississippian volcanic sequence are similar in many respects to the Kuroko-type volcanogenic massive sulphide deposits of Japan. The Pelly Mountains deposits, however, are among the first known occurrences in the world of Kuroko-type mineralization in a rift environment. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
57

Geology and genesis of copper deposits and associated host rocks in and near the Quill Creek area, southwestern Yukon

Campbell, Susan Wendy January 1981 (has links)
The Kluane Ranges are underlain by a sequence of stratified rocks ranging in age from Permian to Triassic, cut by .Cretaceous and Tertiary intrusions. Flow and pyroclastic rocks of Lower Permian Station Creek Formation were probably part of a volcanic arc environment. Argillaceous and tuffaceous rocks of the Transition Zone of Station Creek Formation and overlying sedimentary rocks of Lower Permian Hasen Creek Formation were deposited in a subaqueous environment, possibly a back-arc basin. Upper Triassic basalts of the Nikolai Greenstone are largely subaerial and were probably a product of rift volcanism. Lower Triassic Kluane gabbro-ultramafic complexes are sill- or sheet-like bodies, divisible into a Lower Group (within the Transition Zone) that consist of peridotite and dunite with associated nickel-copper sulphide deposits, and an Upper Group (within Hasen Creek rocks) that consist of gabbro and peridotite but with no known associated nickel-copper deposits. The ultramafic rocks are piagioclase-bearing and chemically are pyroxenitic and peridotitic komatiites. Bulk chemical composition of the Quill Creek complex is similar to that of pyrolite and calculations show the complex could have formed from an upper mantle diapir, affected by 40 percent partial melting and composed of residual olivine crystals and ultramafic liquid. Prominent copper lode deposits in the Kluane Ranges include: (1) vein and disseminated types in Station Creek volcanic rocks; (2) nickel-copper associated with Kluane complexes; and (3) vein-type in the Nikolai Greenstone. A narrow, positive range of sulphur isotopic compositions for vein sulphides in Station Creek Formation contrast sharply with a large range for those in the Nikolai Greenstone. The former deposits resulted from only local mobilization of sulphur (and metals) during metamorphism in a closed system, whereas mineralization in the Nikolai Greenstone involved considerable variation in chemical parameters of ore fluids in an open system with more than one source of sulphur. Anomalously negative sulphur isotopic values for nickel-copper sulphide bodies resulted from contamination of magmatic sulphur by 30 to 60 percent sulphur from wall rocks. Much of this contamination occurred prior to or during segregation of an immiscible sulphide liquid as at Quill Creek, with further contamination during injection of still liquid sulphide bodies into footwall rocks in the case of Canalask deposit. Substantial contaminant.sulphur may have been crucial in achieving sulphur saturation of magmas of Lower Group Kluane complexes and subsequent formation of associated nickel-copper sulphide deposits. Isotopic data for both magmatic sulphides and sulphur-bearing country rock support a strong case for a general sulphur contamination model for nickel-copper deposits related to mafic and ultramafic intrusions on a worldwide scale. Pyrite in wallrock is considered to be the most likely general source of sulphur contributed to ultramafic magmas and several different stages of sulphur contamination are possible throughout consolidation of the magmas and its associated sulphides. Sulphur transfer to the magma can occur by bulk country rock assimilation or by fluid ingress where the fluid derives sulphur from the contact zone by incongruent melting of pyrite or by complete dissociation of pyrite. Important features of this model, having economic implications, are: (1) emplacement of the ultramafic complex as a magma; (2) presence of sulphur-bearing country rocks; and (3) presence of a sulphur-depletion halo adjacent to the ultramafite. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
58

Babbage River delta and lagoon : hydrology and sedimentology of an Arctic estuarine system

Forbes, Donald Lawrence January 1981 (has links)
Inputs, transfer processes, and storage characteristics of water and sediment have been investigated in a 40-km² estuarine system on the central Yukon coast. The setting is transgressive, microtidal, and high-latitude (69°N). The Babbage Estuary system can be subdivided into fluvial, tidal-distributary, delta-plain, intertidal, lagoon, marginal-supratidal, and barrier subsystems, each associated with one or more distinctive depositional environments and characteristic lithofacies assemblages. The structure of the system has been examined in terms of links between subsystems and overall system response to input perturbations. Although the propagation of tide and surge within the estuary may be treated as a quasi-linear stochastic process, transfers of fluvial water and sediment through the system are highly non-linear. Furthermore, the parameters of the system change dramatically on an annual cycle. Inputs and associated system responses are dominated in the short run by seasonal- and synoptic-scale variance, the former reflecting major seasonal adjustments in the phase distribution, circulation process, iand input regime of the estuary. The annual salinity cycle, with a range of at least 60 ppt, exhibits a short reaction and long relaxation response to major snowmelt runoff inputs in May or June, when salt water is flushed completely out of the estuary. Wind-generated waves are effectively absent from the system during 8-9 months of the year, but play a major role during the open-water season. Although direct transport of sediment by ice is relatively unimportant, ice effects are pervasive; they include, in addition to restriction of winter runoff and surface wave generation, creation of hypersaline conditions, control of the sedimentologically important flood events on deltaic supratidal flats, enhanced rates of coastal recession due to thermal degradation of ground ice, and production of distinctive thermokarst morphology on supratidal surfaces. Water level, storage volume, salinity, and suspended sediment series during the open-water season in the lagoon are dominated by synoptic-scale wind effects. In the delta, the major synoptic-scale anomalies of sediment concentration are related to storm runoff. Fluvial clastic sediment inputs to the estuary exceed 10⁸ kg A⁻¹ almost an order of magnitude greater than the estimated littoral transport input. More than 97% of the fluvial input may occur in June; of this, approximately half may be exported directly from the system. At long time scales, the estuarine system has been dominated by rising sea level and coastal recession; Holocene climatic fluctuations may also have been important. A transgressive sequence has developed, including various distinctive features, notably the absence or limited development of aeolian, backbarrier-margin, tidal-delta, and intertidal marsh facies, a largely afaunal intertidal component, and deltaic deposits with poorly developed levees and abundant lake basins. The basal fluvial component includes a sinuous gravel channel assemblage of a hitherto poorly documented type. The Babbage Estuary barrier sequence is primarily transgressive, but incorporates localized elements of progradational and inlet-migration models. Examples of major transgressive, progradational, and inlet-fill barrier sequences occur in close proximity on the central Yukon coast. / Arts, Faculty of / Geography, Department of / Graduate
59

Massive ice in coarse-grained sediments, Western Canadian Arctic

De Pascale, Gregory P. January 2005 (has links)
No description available.
60

The palaeobotany and stratigraphic sequence of the pleistocene Klondike "muck deposits".

Campbell, John Duncan, 1923- January 1952 (has links)
No description available.

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