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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.
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A substantial upward shift of the alpine treeline ecotone in the southern Canadian Rocky MountainsRoush, William Morgan 04 January 2010 (has links)
Changes within and beyond the alpine treeline ecotone are hypothesized to respond to
climatic changes and to be controlled by site-specific conditions. Repeated photographs
show significant changes in the alpine treeline ecotone of Goodsir Pass in Kootenay
National Park, B.C. over the past century. Field work revealed increases in tree density
within the ecotone, and a 150 vertical metre increase in the elevation of the ecotone, at a rate
of 2.2 metres/year. Change within the ecotone of Goodsir Pass is more closely related to
temporal climatic variability than to site-specific spatial variability. Repeated photographs
from three National Parks in the southern Canadian Rocky Mountains show this change to
be a typical but dramatic example. Results at several scales indicate that the occurrence,
magnitude and type of change in the alpine treeline ecotone and the drivers of that change
are most influenced by the regional ecologic and geo-climatic setting or context.
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Age, geochemistry, and fluid characteristics of the MAX porphyry Mo deposit, southeast British ColumbiaLawley, Christopher John Michael 11 1900 (has links)
MAX is a porphyry Mo deposit located near Trout Lake village in southeastern British Columbia. Mo mineralization is hosted by variably-altered calc-alkaline granodiorite dikes. Quartz veins have been subdivided into a paragenetic sequence based on vein style and crosscutting relationships. Post-magmatic Pb-Zn-Ag-bearing veins crosscut Mo-bearing veins. Similarities in fluid chemistry from both vein types suggest a genetic link between porphyry Mo mineralization and base-metal veins.
Three molybdenite samples were collected from early and late Mo-bearing veins for Re-Os dating to constrain the timing of Mo-mineralizing events within the paragenetic sequence. All three dates overlap within analytical error, and yield a weighted average age of 80.3 ± 0.2 Ma. These dates are in excellent agreement with two 206Pb/238U weighted-average ages of the Trout Lake stock at 80.2 ± 1.0 Ma and 80.9 ± 1.6 Ma, indicating that the magmatic and hydrothermal ore-forming events were coeval and cogenetic.
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An agent of change: William Drewry and land surveying in British Columbia, 1887-1929Cameron, Darby 26 August 2009 (has links)
In 1887, following the completion of the CPR to the Pacific, William Stewart Drewry took part in the Topographical Survey of Canada's first experiment with photographic surveying, which he applied to the Rocky Mountain Railway Belt. He then surveyed the rich mining districts of BC during the Kootenay hardrock mining boom (1893-1909). In 1909, he became BC's first and only Chief Water Commissioner and, in 1911, he returned to surveying as BC's Inspector of Surveys. From 1913 until his retirement in 1929, he surveyed for government and in private practice. Throughout his career, Drewry operated between two land systems: first, a system based on customary rights and local obligations; and, second, a system based on private property and market exchange. Drewry implemented the latter capitalist system, attempting to empower the settlement society, which had the effect of ensuring corporate dominance and, to Drewry's dismay, monopolization of the BC landscape.
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