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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.
81

GEOLOGY, HYDROTHERMAL ALTERATION AND MINERALIZATION OF THE GOLD EAGLE DEPOSIT: A NEW DISCOVERY IN THE RED LAKE CAMP, CANADA

MARSDEN, SIAN 02 April 2012 (has links)
Greenstone belts have been recognized as highly prospective settings for high grade gold mineralization, and are host to a number of world class quartz-carbonate vein deposits, which account for approximately 13% of the cumulative global gold production. In Canada, the Archean Red Lake Greenstone Belt hosts one of Canada’s richest gold districts (cumulative production to 2008 of over 24 M oz at 0.461 oz/t). Recently, there have been many discoveries in the district including the Gold Eagle occurrence (also referred to as the Bruce Channel Deposit and Cochenour project), which has an inferred resource of 2.7 million ounces of gold at an average grade of 11.04 g/t Au. The auriferous ore zones in the Gold Eagle Deposit are hosted in volcano-sedimentary rocks of the Balmer Assemblage (2.99-2.96 Ga), which is controlled by a major north trending, west dipping deformation corridor sub-parallel to the Balmer Assemblage-Bruce Channel Assemblage contact. The vertical extent of the mineralization is controlled by the “Cochenour Thrust” that extends into the adjacent Cochenour-Willans Mine. The four main ore zones are structurally controlled within a NS, west dipping fault corridor and consist of: 1) the quartz-actinolite zone; 2) banded iron formations, 3) sulphide replacement zones and 4) footwall ore zones. The deposit has undergone pervasive pre-ore biotite and carbonate alteration, two gold events with the first associated with silicification and late actinolite-tremolite and the second associated with arsenopyrite sulphidation and iron-rich biotite and post-ore quartz and carbonate veinlets. Late faults (including black line faults) have contributed to the complexity and discontinuity of the ore bodies. / Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2012-03-30 10:53:12.446
82

The ecology of sediment bacteria and hypolimnetic catabolism in lakes : the relative importance of autochthonous and allochthonous organic matter

Schallenberg, Marc January 1992 (has links)
Microbial metabolic activity in the hypolimnia and sediments of lakes drives the recycling of organic matter both through mineralization and the production of microbial biomass, which may be utilized by grazers. A correction factor was developed based on the water content of sediment samples that corrects sediment bacteria microscopic counts for masking due to sediment particles. Using this correction factor, it was found that sediment bacterial biomass in 22 lakes was positively related to an indicator of the rate of allochthonous organic matter input to lakes. However, the total hypolimnetic carbon mineralization rate of lakes, which integrates both sediment and hypolimnetic water column mineralization, was found to be driven mainly by phytoplankton carbon and to occur mainly in the hypolimnetic water column. Indeed, various hypolimnetic and sediment catabolic processes were found to show a strong positive relationship with indicators of autochthonous organic matter standing stocks and production. In no cases were the processes significantly positively correlated with allochthonous organic matter standing stocks. Results of this research show that autochthonous primary production drives carbon recycling in the hypolimnetic water column, with the ultimate fate of this production being determined principally by the hypolimnetic thickness. The main fate of allochthonous organic matter in lakes is to become a major component of sediment organic matter where it likely drives a much slower catabolism due to its recalcitrance.
83

Organic matter mineralization in lake sediments : a within and among lake study

Den Heyer, Cornelia E. January 1996 (has links)
Organic matter mineralization by sediment bacteria was measured by the accumulation of DIC + CH$ sb4$ in the water overlying intact cores taken from littoral and profundal sediments of 9 lakes. The variability in areal carbon mineralization was much greater within lakes than among lakes, with the rate of organic matter mineralization in littoral sediments, on average, 3-fold higher than in the deeper sediments. / Sixty percent of the variation in summer carbon mineralization rates is explained by site depth, a surrogate variable which incorporates the effect of temperature and may also be reflecting organic matter quality and/or supply. Lake-specific variables become useful predictors of carbon mineralization only after the site depth is considered. / A comparison of the mineralization in sediments overlain by epilimnetic water to the whole lake sediment mineralization demonstrates the overwhelming importance of the littoral sediments in organic matter mineralization, with more than half (54-100%) of the mineralization in the sediments occurring in the littoral zone. However, the littoral sediments account for less than 20% of the gross respiration in the epilimnion. (Abstract shortened by UMI.)
84

Distribution and resource utilization of littoral zone fishes along the production gradient of Lake Memphremagog

Gascon, Pierre Dominique. January 1976 (has links)
No description available.
85

Geology, Geochemistry and Geochronology of the East Bay Gold Trend, Red Lake, Ontario, Canada

Gallagher, Shaun 10 April 2013 (has links)
The Red Lake greenstone belt is considered to be one of Canada’s premier gold producing regions with the Red Lake Gold Mines having produced >24 million ounces of gold to date. The East Bay Trend is a large structural corridor that parallels the East Bay of Red Lake, Ontario and is interpreted to be a manifestation of the regional D1 structure that crosscuts this complexly folded greenstone belt. The southernmost 8 km of this corridor is host to a variety of small gold deposits that demonstrate an assortment of mineralization styles. This study aims to: (1) better define veining styles and characterize the mineralizing fluids using petrography, fluid inclusions, geochronology and stable isotopes, (2) compare barren and auriferous veins from deposits along the East Bay Trend, and (3) compare the fluid history of the East Bay Trend to the Campbell-Red Lake gold deposit to determine the gold potential along this trend.
86

Developing a domestic water supply for Winnipeg from Shoal Lake and Lake of the Woods: the Greater Winnipeg Water District Aqueduct, 1905 – 1919

Ennis, David 07 April 2011 (has links)
The water source for The City of Winnipeg is Shoal Lake near the Manitoba-Ontario border, 145km east of the city, and is delivered by a gravity powered system known as the Winnipeg Aqueduct. It was built during World War 1. The system is 150km in length, primarily in an enclosed conduit operating under open channel flow, and crosses eight rivers. The project was built by the Greater Winnipeg Water District. The concept of the Water District, is administration, the design of the aqueduct’s components, the contract administration, and the construction procedures employed in implementing the system are explained. The purchase and topographical modification of land belonging to the First Nation residents of Shoal Lake Band 40 was essential to the development of the project. There are ongoing issues for this First Nation arising from that purchase.
87

The rapid bioassessment of lakes: protocol design and testing in Manitoba's boreal shield

Hynes, Kristin 07 September 2012 (has links)
Rapid bioassessment (RBA) methods have largely been used for streams and rivers, with little development of equivalent methods to be used in lakes. This has restricted the assessment of lakes because traditional methods are time- and cost-intensive. Here I show that a newly designed RBA protocol can be used to monitor a wide range of boreal shield lakes effectively. Seventy per cent of lakes with over 25% of their shoreline developed with cottages were assessed as impacted using a multimetric index. This research has built on previous knowledge, placing new emphasis on standardizing sampling efforts by depth, habitat type (cobble sediments) and sample area in lakes. My recommendations provide water resource managers with methods that can be used as a screening tool to monitor a large group of lakes affected by a variety of stressors.
88

A comparative study of the phytoplankton phosphorus status in Lake Memphremagog /

Sproule, Jennifer Lee. January 1977 (has links)
No description available.
89

A limnological investigation of a retired stone quarry of East Central Indiana

Kalisz, Walter Ralph January 1976 (has links)
There is no abstract available for this dissertation.
90

Mammals of the Huntington Reservoir, Huntington and Wells Counties, Indiana

Reising, Johnny W. January 1974 (has links)
A survey of the Mammalian fauna of the Huntington Reservoir Area in Huntington and Wells Counties was conducted from March 1, 1973 through February 28, 1974. Collected specimens were identified to species, catalogued, and made into study skins and/or skulls prior to deposition in the Ball State University Mammal Collection. Data were recorded on body measurements, weights, reproductive condition, and skull measurements. These data were compared to previous mammal investigations in Indiana.The study revealed the presence of 27 species of mammals on or near the Huntington Reservoir Study Area. Twenty-one species were Collected and/or examined by the author, and the additional six species were collected and/or observed by Reservoir personnel.

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