<p> The igneous rocks of the Killarney Complex, Killarney, Ontario exhibit numerous echelon fracture sets near their contact with mylonites of the Grenville Front. The echelon fracture sets are younger than the Grenville Front mylonites and are therefore part of the late brittle history of the Grenville Province. These fracture sets are confined to a small (5 km2) area but display a wide range of orientations and morphologies. They can be divided into four peak orientations and these can be compared with inferred stress states for several periods in the tectonic history of the Grenville Province from 1200 Ma to the present. Based on these orientations and other observations it is suggested that the echelon fracture sets formed over a period of time spanning the end of the Grenvillian Orogeny 1000 Ma) to the beginning of Ottawa-Nippissing rifting (post 575 Ma). </p> <p> Measurement of the geometrical characteristics of the echelon fracture sets and comparison with those quoted in the literature has led to the conclusion that the geometry of an echelon fracture set does not unequivocally indicate its origin or mode of formation. </p> <p> Current models using fracture-zone angle and overlap ratio for the classification of echelon fracture sets seem to be unapplicable to the echelon fracture sets examined in this study and must be used with caution. The echelon fracture sets studied here are interpreted to have formed in "shear zones" and to consist of dominantly tensile fractures. Some of the fractures have originated as shear fractures or have undergone shearing at some point in their history. </p> / Thesis / Master of Science (MSc)

Ecologists studying acid-damaged zooplankton communities have often documented a time lag in recovery following pH increases. While previous work has provided a solid understanding of the local factors that may delay recovery (e.g. competition), less is known about the role of dispersal. The work in this thesis was conducted to test the hypothesis that dispersal limitation contributes to delays in the recovery of acid-damaged zooplankton communities. To assess the role of dispersal during recovery I pursued three objectives: 1) To measure dispersal in the field and determine the relative importance of various dispersal vectors for contributing acid-sensitive colonists to lakes; 2) to determine if spatial structure in recovering zooplankton communities exists across the landscape independent of environmental gradients; and 3) to determine if an interaction between dispersal and local environmental variables could influence recovery. Data collected for Objective 1 demonstrated that overland dispersal rates for acid-sensitive species in Killarney Park were relatively low, but some species were found emerging from the diapausing egg bank or dispersing through streams to recovering lakes. Spatial modeling and variation partitioning analyses for Objective 2 revealed spatial patterns indicative of dispersal limitation in recovering Killarney Park zooplankton communities. Enclosure experiments conducted for Objective 3 suggested that the colonization of the acid-sensitive copepod Epischura lacustris may be influenced by an interaction between dispersal levels and pH, such that higher dispersal levels may be required for establishment in lakes that are early in the process of pH recovery. Enclosure experiments also indicated that community resistance and low dispersal levels might hinder the reestablishment of the acid-sensitive copepod Skistodiaptomus oregonensis. Taken together, my results strongly suggest that dispersal limitation could contribute to delays in zooplankton community recovery. The recovery of acid-sensitive copepod species may be particularly difficult, as their reestablishment in recovering lakes appears to be influenced by Allee effects, community resistance, and an interaction between pH and dispersal levels. While dispersal rates could be artificially increased by human intervention, this would carry the risk of introducing invasive species. As a result, patience and continued monitoring of recovering lakes may be the best management approaches at this time. / Thesis (Ph.D, Biology) -- Queen's University, 2011-12-20 22:49:05.193

<p> Forty-Three cores were collected from the region of the Killarney Igneous Complex, southeast of the town Killarney. These cores were analysed by measuring geophysical properties such as bulk susceptibility, percent anisotropy, magnetic foliation and lineation and remanence. The magnetic fabric measured indicated a regional fabric. In some areas the fabric was completely overprinted due to localised deformation. Measured remanence may make it possible to determine the effect of previous deformations; however, none was seen in this study. </p> <p> The petrological fabric was also investigated by taking thin sections perpendicular to the long axis of the core. Again it was possible to see a regional and localized deformation pattern due to reduced grain size, grain alignment and recrystallization. </p> <p> Measurements collected from the samples determined that both the magnetic fabric and petrological fabric showed indications of being near areas of greater deformational intensities. A relationship was then established between the magnetic fabric and petrological fabric on a fine scale. This relationship may aid in determining direction and extent of deformation in the rock bodies when it is not easily identifiable in the field. </p> / Thesis / Bachelor of Science (BSc)

The nature of the inter-relationship of valley-side slopes and the streams at their base is regarded as being of fundamental significance in the study of landscape morphology. One aspect of this relationship, the problem of the development of valley-side asymmetry in east-trending valleys under the joint influence of microclimatic and stream controls, is investigated in two areas of uniform, flat-lying beds, using the approach and techniques of experimental design. Valleys in both study areas have been formed during the last 12,000 years, so that the importance of fossil slope forms is minimal. The variation in lithology between the two areas is held to be of less consequence than the difference in climatic regimes, as far as the type of asymmetry developed. The moister of the two areas, S.W. Manitoba, shows the typical, valley-wide asymmetry regarded as characteristic of non-periglaclal regions, with north-facing slopes significantly steepened by 3.1°, on average: the effects of basal steepening by meandering streams are additive with the microclimatic differences. In the drier area, S.E. Wyoming, the effects of the two controls are non-additive, and asymmetry is a purely localised development created by the over-steepening of shaded, north-facing undercut slopes. The moisture availability in this environment is probably increased by the formation of snowdrifts in the winter months. Asymmetry resulting from differences in aspect is statistically insignificant both in east-trending valleys without defined stream channels and in south-trending valleys with meandering streams. The absolute maximum angle is found to be an excellent indicator both of local changes in slope form and of the nature of the profiles as a whole. The degree of organisation of all profiles studied, in relation to the maximum angle, is high, with the exception of the south-facing slopes in those east-trending valleys in Wyoming which lack defined channels. In general, the maximum angle appears more directly related to the other geometric features of the profile than to the characteristics of soil, vegetation or nearby stream channel. A consideration of all available data on multiply-controlled asymmetry in non-periglacial areas leads to the conclusion that differences in steepness of slopes with northern and southern aspects are more likely to develop in regions of comparatively low humidity and that the valley-wide asymmetry found in Manitoba is the most common form. The strictly localised asymmetry developed in the Wyoming valleys appears to be a specialized phenomenon confined to a narrow area of semi-arid climate. It is suggested that the local conditions of moisture availability are the prime controls of multiply-controlled valley asymmetry, in that they will determine the relative importance of slope and channel processes and hence the nature of the valley-side development. / Arts, Faculty of / Geography, Department of / Graduate