3 resultados para Ecology--Ontario, Lake (N.Y. and Ont.)
em Memorial University Research Repository
Resumo:
The L-moments based index-flood procedure had been successfully applied for Regional Flood Frequency Analysis (RFFA) for the Island of Newfoundland in 2002 using data up to 1998. This thesis, however, considered both Labrador and the Island of Newfoundland using the L-Moments index-flood method with flood data up to 2013. For Labrador, the homogeneity test showed that Labrador can be treated as a single homogeneous region and the generalized extreme value (GEV) was found to be more robust than any other frequency distributions. The drainage area (DA) is the only significant variable for estimating the index-flood at ungauged sites in Labrador. In previous studies, the Island of Newfoundland has been considered as four homogeneous regions (A,B,C and D) as well as two Water Survey of Canada's Y and Z sub-regions. Homogeneous regions based on Y and Z was found to provide more accurate quantile estimates than those based on four homogeneous regions. Goodness-of-fit test results showed that the generalized extreme value (GEV) distribution is most suitable for the sub-regions; however, the three-parameter lognormal (LN3) gave a better performance in terms of robustness. The best fitting regional frequency distribution from 2002 has now been updated with the latest flood data, but quantile estimates with the new data were not very different from the previous study. Overall, in terms of quantile estimation, in both Labrador and the Island of Newfoundland, the index-flood procedure based on L-moments is highly recommended as it provided consistent and more accurate result than other techniques such as the regression on quantile technique that is currently used by the government.
Resumo:
This dissertation employs an eclectic approach to archaeology, in which various theories from culture history, processualism, and post-processualism are used together as aspects of a single approach to archaeological history. This multifocal methodology is discussed, and used to organize and present the archaeological survey results from Ashuanipi, a large lake in the Lake Plateau Region of the Quebec Labrador Peninsula. Questions related to predictive modelling, cultural resources management, boreal forest ecology, landscape change, archaeological theory and practice, and Innu history are raised throughout the process – some of these question are answered, while others are guideposts for future research.
Resumo:
The Nimish Subgroup igneous suite is a linear belt of volcanic and plutonic rocks in the Dyke Lake area of the southern Labrador Trough. The volcanics are interbedded with the sediments of the Wishart and Sokoman Formations of the Aphebian aged, Knob Lake Group. The sokoman Formation forms a time stratigraphic horizon that separates the lower Petitsikapau Lake Formation from the upper Astray Lake formation of the Nimish Subgroup. The occurrence of these volcanics within the Knob Lake Group is unique relative to Labrador Trough stratigraphy, as elsewhere the Knob Lake Group is a dominantly sedimentary succession and volcanics are restricted to the younger Doublet Group. Stratigraphic relationships between the Nimish Subgroup and the Sokoman formation indicate contemporaneous volcanic, clastic and chemical sedimentary activity. The internal stratigraphy of the Sokoman Formation exhibits a three-fold subdivision that is broadly correlatable with similar subdivisions in the Schefferville "main ore zone", 30 miles to the northwest. A detailed facies and paleogeographic model relating the volcanic activity to iron formation deposition in the Dyke Lake is presented. The rocks of the Dyke Lake area have been affected by lower greenschist facies metamorphism during the Hudsonian orogenic event, circa 1735 my. Geochemical evidence indicates that the igneous rocks of the Nimish Subgroup have been metasomatized with large degrees of mobility in Na₂O, K₂O, CaO, MgO, SiO₂, FeO and Fe₂O₃ suspected. The "immobile trace elements", Ti, Zr, Nb, Y and Ga imply that the Nimish lavas are a mildly alkaline suite that has an alkali basalt-trachyandesite-comendite differentiation scheme. The rare earth element, REE, geochemistry of the Nimish Subgroup is supportive of the alkaline nature of the volcanics and has been used to model the fractional crystallization petrogenesis involved in the two volcanic cycles. The geological, geochemical and geophysical evidence indicates that the Nimish Subgroup lavas are possibly a rift facies, alkaline suite related to the tensional tectonic regime that preceeded the extrusion of voluminous tholeiitic lavas of the Doublet Group.