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The peninsula effect is a pattern of diversity wherein species richness decreases along a peninsula from base to tip and is attributed to three mechanisms: historical processes, habitat gradients, and immigration-extinction equilibrium. Numerous studies have reported conflicting results involving the existence, cause, and validity of the peninsula effect in part because they did not account for effects of history or habitat on species richness patterns and because most previous research focused on organisms that actively disperse, which could confound results with behavioral habitat selection. Florida poses an excellent opportunity to study the peninsula effect because of its geological history and its unique ridges have similar histories (e.g. age, elevation, and sediment). Habitat changes down the peninsula, from a warm temperate climate in the north to a subtropical climate in the south. I studied freshwater crustaceans in isolated wetlands because crustaceans are diverse and disperse passively among these discrete habitats. My study design and statistical analyses controlled for two of the three mechanisms (habitat and history) that may generate a peninsula effect to better test for the third hypothesis (immigration-extinction equilibrium) on the Florida peninsula. Thirty-one wetlands were sampled for crustaceans monthly from November 2004 through April 2005, or until a site dried. Human disturbance was minimized by choosing isolated, ephemeral wetlands located within state reserves, parks, and forests located on four major ridges: Trail, Brooksville, Mount Dora and Lake Wales. I measured several environmental variables to assess habitat variation among sites. Limnological parameters included temperature, pH, dissolved oxygen, conductivity, chlorophyll á, pheophytin, total nitrogen, total phosphorus, and total hardness. Other habitat variables included surface area, distance to nearest water body, fish presence or absence, hydroperiod, total transmitted light and canopy openness. Crustacean species were identified to the lowest practical taxonomic level (typically species) and recorded as present or absent. A total of 53 different crustaceans were identified, including 41 cladocerans, 10 copepods, and 2 ostracods. In a multiple regression, environmental variables and sampling effort accounted for 57% of the variation in species richness. Regression of remaining variation (residuals) against latitude, which measures position along the peninsula, was not statistically significant. The same pattern was obtained when the sequence of regressions was reversed. Therefore, the peninsula effect does affect the species richness of freshwater crustaceans inhabiting ephemeral wetlands on Florida's ridges. Instead, variation in species richness was determined mainly by habitat differences, particularly the complex interaction of phosphorus levels, isolation, fish presence or absence, and hydroperiod. This study may serve as a model for more thorough analyses of mechanisms (history, habitat, and immigration-extinction) of a peninsula effect in other taxa.

Aquifers associated with the Oak Ridges Moraine (ORM) supply drinking water to more than 200,000 people. These aquifers are often overlain by relatively lower permeability till deposits (aquitards) often considered to provide protection to underlying aquifers. A transformer station is under construction by Hydro One (H1) on 11 hectares of H1 owned land on the ORM in the Municipality of Clarington, Ontario. The surficial geology is mapped as till. It is important to consider potential groundwater impacts of this transformer project. As part of the environmental assessment conducted by H1, groundwater information was collected from the property and from nearby homeowner wells. This thesis concerns the geology and groundwater conditions beneath the property utilizing both existing information and also study of a drill hole, commissioned by H1, continuously cored into bedrock at 127.76 m depth. There is a paucity of deep hydrogeological information over the eastern half of the ORM. This thesis reports on the hydrogeology of the local area, which is in a hydrologic setting common throughout much of the ORM, thereby providing valuable information to inform the regional context. The cored hole showed the presence of two deep regional sand aquifers, known as the Thorncliffe and Scarborough aquifers, overlying bedrock. The surficial till unit is interpreted to be over 75 m thick and includes a near-surface sand layer and two deeper, thin sandy layers within this very dense till. This study, conducted as a collaboration between the Universities of Guelph and McMaster, represents the first phase of a continuing study of the hydrogeology of the H1 property and adjacent area. The next phase includes installation of a depth-discrete, multilevel monitoring system (MLS) for water level measurement and groundwater sampling at 16 different depths. This thesis includes a design for this MLS to be installed beside the deep hole. / Thesis / Master of Science (MSc) / This thesis concerns the geology and groundwater conditions at the Hydro One transformer station under construction in the Municipality of Clarington, located near the southwestern periphery of the Oak Ridges Moraine (ORM). The ORM, throughout its full extent north of Lake Ontario, has aquifers supplying drinking water to more than 200,000 people, some near the transformer station. The thesis, which is the first phase of a longer term study, uses information obtained from a borehole that provided continuous core samples from near ground surface down through deposits formed by Pleistocene glaciers and into the shale bedrock at 127 m depth. This borehole and four monitoring wells installed by Hydro One nearby, provide the first deep groundwater information of its type available from this part of the ORM and indicate the presence of two deep regional sand aquifers and suggest the occurrence of two thin intermediate depth sand aquifers.

The lithosphere of Mars accommodates shortening through folding and faulting, producing landforms qualitatively categorized as wrinkle ridges or lobate scarps. However, we lack a deep understanding of the morphological differences between these landforms. This study aimed to develop a quantitative model for shortening landform classification based on surface morphology and subsurface architecture. We developed this model by mapping 100 landforms in a GIS, recording parameters for each landform. We conducted a Discriminant Function Analysis (DFA) using these morphometrics. This DFA produced a predictive linear function for categorizing wrinkle ridges and lobate scarps. We then modeled the subsurface structural geology of 50 landforms using MOVE Structural Geology Modeling Software and conducted a second DFA on subsurface metrics. These analyses revealed the three most important variables when classifying shortening structures. Our results show that by using the surface morphology and subsurface geometry together, they can be distinguished quantitatively 96% of the time.

In order to deliver statistical and qualitative backing to latent fingerprint evidence, algorithms are proposed (1) to perform fingerprint matching to aid in quality assessment, and (2) to discover statistically rare features or patterns in fingerprints. These features would help establish an objective minimum-quality baseline for latent prints as well as aid in the latent examination process in making a matching comparison. The proposed methodologies use minutiae triplet-based features in a hierarchical fashion, where not only minutia points are used, but ridge information is used to help establish relations between minutiae. Results show (1) that our triplet-based descriptor is useful in eliminating false matches in the matching algorithm, and (2) that a set of distinctive features can be found that have sufficient discriminatory power to aid in quality assessment. / Master of Science

Hydrothermal processes at oceanic spreading centers are largely influenced by changing magmatic heat input. I use the FISHES code to investigate the evolution of surface temperature and salinity as a function of time-varying heat flux at the base of a two-phase, vapor-brine hydrothermal system. I consider a two-dimensional rectangular box that is 1.5 km deep and 4 km long with homogeneous permeability. Impermeable, insulated conditions are imposed on the left and right hand boundaries. To simulate time-varying heat flux from a sub-axial magma chamber of 500 m long half-width, I consider a variety of basal boundary conditions: (1) a constant heat flux with an value of 130 W/m2; (2) a sinusoidal heat flux with a period of 6 years and an amplitude ranging between 100 and 50 W/m2; (3) step, random, and exponential heat fluxes ranging between 200 and 15 W/m2; and (4) an analytical function of temporally decaying heat flux resulting from a simulated cooling, crystallizing magmatic sill. As a result of the investigation I find: (1) changes in bottom temperature and salinity closely follow the temporal variations in magmatic heat inputs; (2) the surface temperature response is severely damped and high frequency variations in heat flow are not detected; (3) in regions where phase separation of vapor and brine occurs, surface salinity variations may be recorded in response to changing conditions at depth, but these are smaller in amplitude. / Master of Science

Hydrothermal systems associated with oceanic spreading centers account for a quarter of Earth's total heat flux and one third of the heat flux through the ocean floor. Circulation of seawater through these systems alters both the crust and the circulating fluid, impacting global geochemical cycles. The warm vent fluids rich in nutrients support a wide variety of unique biological communities. Thus, understanding hydrothermal processes at oceanic spreading centers is important to provide insight into thermal and biogeochemical processes. In this dissertation I present the results of numerical modeling efforts for mid-ocean ridge hydrothermal systems. In the three manuscripts presented, permeability emerges as a key controlling factor for hydrothermal venting. In the first manuscript, I use 2-D numerical models to find that the distribution of permeability in the crust controls fluid velocity as well as the amount of mixing between hot hydrothermal fluids and cold seawater. This, in turn, effects the temperature and composition of fluids emerging on the surface. For the second manuscript, I construct single-pass 1-D models to show that a sudden increase in permeability caused due to magmatic or seismic events in the seafloor causes a sharp rise in the fluid output of the system. This, in conjunction with steep thermal gradients close to the surface, results in a rapid increase of venting temperatures. In the third manuscript, I develop a particle tracking model to study fluid trajectories in the subsurface. The results show that permeability distribution in the subsurface governs fluid paths and consequently, the residence time of fluids in the crust. Based on the work presented in this document, I conclude that permeability distribution, both local and field scale, exerts a major control on hydrothermal circulation in the subsurface and on the temperature and composition of venting fluids on the surface. / Ph. D.

Seafloor hydrothermal systems play a key role in Earth s energy and geochemical budgets. They also support the existence and development of complex chemosynthetic biological ecosystems that use the mineral-laden fluids as a source of energy and nutrients. This dissertation focuses on two inter-related topics: (1) the heat output at mid-ocean ridge (MOR) hydrothermal sites, and (2) the hydrothermal response to earthquakes at mid-ocean ridges. The response of mid-ocean ridge hydrothermal systems to seismic and magmatic activity could provide a means of using seafloor observations to assess processes occurring at crustal depths. Three decades of study of the ocean floor have made clear that tectonic/volcanic perturbations and changes in the hydrothermal activity are correlated. Yet, this relationship is still highly misunderstood. In this dissertation, we developed a mathematical model of hydrothermal circulation affected by magmatic and/or tectonic events occurring at depth. We showed that the perturbations they generate need not propagate through the entire upflow zone, as previously suggested, but need only affect the movement of the boundary layers. In this case, the fluid residence time in the discharge zone is on the order of years. The determination of heat output at MOR hydrothermal sites provides important constraints on the physics of these processes. Yet, such measurements are still very limited, available only for ~30 sites out of the ~10^3 estimated worldwide. This dissertation reports the first measurements of hydrothermal heat output at 9°50' N on the East Pacific Rise (EPR), which has been the most intensively studied site for the past 20 years (~10^2 expeditions). The values we obtained helped constraining the afore-mentioned mathematical model, which was tested based on the March 1995 microearthquake swarm near 9°50' N, EPR. Our results showed that the current interpretation based on a thermal cracking episode at the bottom of the upflow zone, may be incorrect. We argue that a diking scenario better explains the seismic and temperature data, while being consistent with the mechanics of inflation of the axial magma chamber in the 9°50' N, EPR area between two major eruptions, in 1991 and 2006.

This diploma thesis deals with the identification of persons by their fingerprints. In the beginning, there is a brief overview of biometric methods. The issue of fingerprints and their automatic processing is very extensive and addresses a large amount of literature. This work describes the various stages processing fingerprints from receiving a fingerprint scan through the methods of enhancing fingerprint, binarization, the detection of minutiae to compare two fingerprints. After a short introduction of biometric techniques is briefly introduced the history of fingerprints as an instrument for identification of persons. Subsequently, there is the description of problems of obtaining fingerprints from older methods that require the transmission medium, to methods of obtaining fingerprints directly into a digital format. There are described basic principles of sensors and the principle of their function. Next part deals with methods of processing digital fingerprint images. These are methods for fingerprint image enhancement, methods for image thresholding, thinning of ridge lines, detection of global and local characteristics of the fingerprint. The next section introduces the basic methods of comparison and classification of fingerprints. The practical part describes the specific implementation of fingerprint processing chain. For each processing stage is implemented one selected method. The result is an application that allows displaying the output of each phase, the comparison of fingerprints 1:1 and also finds a fingerprint in the database, by comparing one fingerprint with many.

Subsidence is one of the main factors controlling the stratigraphy and overall stratal architecture in tectonically active basins. This was particularly important in the Western US Cordilleran foreland and Laramide basins when some other controls were minor, e.g. reduced eustatic fluctuations in the late Cretaceous greenhouse period. The first part of the dissertation examines the upper Campanian Williams Fork Clastic Wedge (WFCW) in southern Wyoming and northern Colorado, through an outcrop and subsurface database. The WFCW built out from the Sevier orogenic belt like earlier clastic wedges, but its large-scale geometry changed as basement involved Laramide structures partitioned it. At the center of the WFCW there is an extensive fluvial sandstone sheet, the Canyon Creek Member of the Ericson Formation. From its proximal to distal reaches (~200 km) there is a first order trend of stratigraphic thickening and net-to-gross reduction, and a change from braided to meandering depositional style. These trends are caused by isostatic rebound of the foreland basin during periods of relative quiescence in the Sevier orogenic belt and by the eastward migration of dynamic subsidence. However, this long spatial trend was markedly modified by differential subsidence across Laramide-style structures. The Campanian age initiation of the Laramide structures appears to be earlier than the Maastrichtian to Paleogene age commonly attributed to the initiation of this orogeny. The second part of this research focuses on the transgressive limb of the WFCW, particularly on two sandstone bodies isolated in marine mudstones in the uppermost Almond Formation. The sandstone bodies previously interpreted as lowstand shoreline deposits are re-interpreted as transgressive shelf ridges generated by tidal currents and storm waves. There are limited examples of ancient tidal shelf ridges published and no facies model was described. Using Almond Fm. outcrops and examples from the literature, the diagnostic characteristics of storm and tidal shelf ridges are presented. The third part of the dissertation investigates the effects of differential subsidence on the large scale stratigraphic infill of a foreland basin through a geometric model and a series of flume experiments. The mathematical model and flume experiments show that despite constant allogenic forcing, three distinct autogenic responses in stratal architecture, associated with the imposed tectonic and sediment supply conditions are possible. The first response was “autoretreat”, where shoreline migration switched from initial progradation to retrogradation. The second response was progradation followed by constant aggradation. The third response was maintained progradation with a markedly accelerating rate, a new autogenic behavior termed “shoreline autoacceleration”. / text