Passive margins along the eastern seaboard of North America formed during early Mesozoic continental rifting and seafloor spreading, tectonic processes that are not fully understood. Seismic refraction and reflection data at the northeastern and north-central Gulf of Mexico and the Grand Banks of Newfoundland, Canada, are used to interpret the deep seismic velocity structure of sediments, crust, and mantle. These interpretations allow for a better understanding of continental rifting, mantle upwelling, magmatism, and seafloor spreading. Magma-poor rifting of the Newfoundland-Iberian margin developed a wide continent-ocean transition zone (COT). I present an analysis of 2-D marine seismic refraction and reflection data from the SCREECH project, including a shear velocity model to constrain the composition of the Newfoundland COT. Comparing SCREECH Line 2 Vp/Vs ratios with depth to potential lithologies supports a COT comprised of hyperextended continental crust and serpentinized mantle. Reconstructions of the opening of the Gulf of Mexico basin are impeded by a lack of seafloor magnetic anomalies and an abundance of sediments that obscure acquisition of seismic refraction datasets. Accordingly, the roles of mantle upwelling, magmatism, and lithospheric extension in this small ocean basin are poorly known. I present new 2-D marine seismic refraction data from the U.S. Gulf of Mexico collected during the 2010 GUMBO project. Rifting in the eastern Gulf of Mexico developed above a zone of anomalously high mantle potential temperatures that led to abundant magmatism. Syn-rift basins in continental crust, high velocity lower crust, a narrow zone of crustal thinning, and seaward-dipping reflectors support this interpretation. Oceanic crust here is thick despite slow seafloor-spreading rates, implying continuation of a thermal anomaly after rifting. In the north-central Gulf of Mexico, transitional crust is consistently thin (~10 km) across a wide zone. Velocity-depth comparisons, asymmetry of the north-central Gulf with the Yucatán margin, and dating of onshore xenoliths support either stretched and magmatically intruded continental crust or a multi-stage episode of seafloor spreading with ridge jumps. I contend that although tectonic inheritance may ultimately influence the location of a passive margin, the rifting process is largely controlled by mantle potential temperature and upwelling rate. / text

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This essay considers the relationship between the creative and philosophical writings of Graça Aranha, in part as response to the critical tendency to exclude the majority of his works when analyzing his oeuvre. Aranha’s major work of philosophy, The Aesthetic of Life, proclaims that aesthetic experience is the “basis of perfection”: the solution the alienation initiated by the duality of consciousness. Yet, the aestheticism of his philosophical treatise is ruthlessly tested through the dramatic embodiment found in his three works of fiction: Canaan (novel), Malazarte (play), The Marvelous Journey (novel). Aranha’s interest in philosophical dialectic is manifested most effectively in the drama of ideas which runs through his fiction. Consequently, Aranha’s works should be evaluated and explicated with attention to the ways in which they comment on each other. In particular, the fictional works suggest a negative aspect to Aranha’s aesthetic concept of the marvelous. The three creative works employ and anticipate ideas found in Psychoanalytic theory, Marxist theory, and Existentialism in order to illustrate that the marvelous experience is a kind of death of the subject. Additionally, this essay contributes to the critical dialogue over Aranha’s place in or outside of Brazilian modernism. The representation of Brazilian dance and ritual found in the two novels are explored as a noteworthy modernist approach to the questions of cultural and aesthetic decadence that influenced the modernist period in both Europe and Brazil. / text

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This dissertation examines the development of the North American air defence system from the beginning of the Cold War until 1956. It focuses on the political and diplomatic dynamics behind the emergence of these defences, which included several radar lines such as the Distant Early Warning (DEW) Line as well as a number of initiatives to enhance co-operation between the United States Air Force (USAF) and the Royal Canadian Air Force (RCAF). This thesis argues that these measures were shaped by two historical factors. The first was several different conceptions of what policy on air defence best served the Canadian national interest held by the Cabinet, the Department of External Affairs, the RCAF and the Other Government Departments (OGDs), namely Transport, Defence Production and Northern Affairs. For the Cabinet and External Affairs, their approach to air defence was motivated by the need to balance working with the Americans to defend the continent with the avoidance of any political fallout that would endanger the government‘s chance of reelection. Nationalist sentiments and the desire to ensure that Canada both benefited from these projects and that its sovereignty in the Arctic was protected further influenced these two groups. On the other hand, the RCAF was driven by a more functional approach to this issue, as they sought to work with the USAF to develop the best air defence system possible. Finally, the positions of the OGDs were shaped by more narrow priorities. For example, C.D. Howe and the Department of Defence Production sought to use these joint radar projects to build up the Canadian electronics industry. Canada‘s air defence policy in the 1950s, therefore, was a compromise between these various conceptions of the national interest. The other major influence on this process was the attitude of the Truman and Eisenhower administrations towards continental air defence. This dissertation will argue that most of the measures to improve the security of the continent emerged because of the efforts of the United States, but at the same time, the Americans‘ level of interest in these defences varied greatly over this period and ultimately were not sustained. Moreover, both these administrations had to overcome opposition from the USAF‘s senior leadership, which preferred an emphasis on the offensive nuclear forces of the Strategic Air Command (SAC) over improved air defences. This dissertation thus makes an important and original argument that contributes to the scholarly literature on the Canada-U.S. defence relationship during the early Cold War. / Thesis (Ph.D, History) -- Queen's University, 2011-09-14 14:08:14.101

The main objective of this work was to understand fundamental processes related to incipient continental collision through studying the tectonostratigraphic evolution of Cyprus, in its Easternmost Mediterranean context. This was achieved by compiling structural, sedimentological and stratigraphic evidence from Late Cenozoic to Recent sequences, and by applying palaeomagnetic and luminescence methods of dating. In particular, the basin-fill of the Neogene basins provides a temporal and palaeogeographic control to interpret syn-depositional and post-depositional structural assemblages. Four neotectonic deformation phases are recognised. The Polis and Pissouri Basins originated as Tortonian depocentres in response to syn-depositional W-E/WSW-ENE D1 extension. The Maroni Basin originated as a Tortonian depocentre in response to syn-depositional NW-SE D1 extension. The difference in extension direction between west and south-central Cyprus is attributed to the curvature of the Cyprus Arc. The Middle - Late Pliocene D2 extensional/transtensional phase re-orientated the Neogene basins and resulted in syn-depositional NW-SE extension. A kinematic change occurred at ~3 Ma, attributed to the collision of the Eratosthenes Seamount with an active trench, the ‘Cyprus Arc’. Early Pleistocene to Recent D3a transpression generated strike-slip faulting along E-W trends, conjugate left-lateral NNE-SSW-trending and right-lateral NNW-SSE-trending strike-slip faults and reactivated Tortonian D1 NW-SE and NE-SW structures. Middle Pleistocene to Recent D3b compression produced intense NE-SW contractional deformation orientated along NW-SE trends. Optically stimulated luminescence (OSL) dating was used as a tool to constrain the D3a/D3b events, by generating a chronology for their associated sediments. D3 transtensional lineaments originated in the early Pleistocene (174.1 ± 20.9 ka < D3a < 76.6 ± 16.43 ka), and are still active today (Cape Kiti: 38.1 ± 13.2 ka < D3a < 12.1 ± 0.1 ka). D3 compressional lineaments originated in the middle Pleistocene, and were still actively growing at 76.8 ± 31.6 ka. To constrain the timing of regional uplift in south and central Cyprus, a magnetostratigraphy was generated for the Plio-Pleistocene units of the Pissouri and Mesaoria Basins. The results indicate that rapid uplift began in the latest Pliocene (c. 2.14 – 1.95 Ma), coincident with the large-scale progradation of Gilbert-type fan deltas into the Pissouri Basin, and the incursion of large fluvial networks into the Mesaoria Basin. In light of the new evidence, three alternative models for the Early Cenozoic to Recent tectonostratigraphic evolution of Cyprus are considered: model 1, subduction/incipient collision; model 2, advanced collision; and model 3, transpression. Some difficulties exist in detail, with all three models. However, at present the working hypothesis is as follows: areas to the east of Cyprus (Syria, S Turkey) were in a collisional setting from Mid-Miocene time onwards. Cyprus remained in an oceanic embayment (Levant Sea) further west and subduction continued during Miocene time. Compressional processes may have been active at depth during this time. Southward extension (trench roll-back) was taking place at a high structural level in S Cyprus, as with many other convergent margin settings (e.g. SW Peloponnese; Aleutians; Sunda arc). Subsequently, the collision of the Eratosthenes Seamount with the Cyprus Arc obstructed subduction and initiated rapid uplift of the Troodos Massif. The initial manifestation of this kinematic change was the generation of E-W-trending strike-slip faults and the development of conjugate left-lateral NNE-SSW-trending and right-lateral NNW-SSE-trending strike-slip faults. Transpression resulted in the reactivation of D1/D2 E-W, NE-SW and NW-SE structures. Subsequent deformation is documented in a compressional lineament in SW Cyprus. In addition, the over-riding plate in southwest Cyprus still appears to be undergoing gravity spreading outwards from the developing collision zone.

Peter Lamarque and Stein Haugom Olsen, in Truth, Fiction, and Literature: A Philosophical Perspective (1994), advance a "no-truth" theory of literature, which has become highly influential in the analytic tradition of the philosophy of art. However, considering the historical precursors that have influenced them, their work has been defined largely without considering certain strands of Continental philosophy. In particular, they do not seriously consider the tradition of Heideggerian phenomenology. In this thesis, by relying on the philosophy of Heideggerian thinker Hans-Georg Gadamer, I argue that Lamarque and Olsen advance their no-truth theory of literature because they consider the concept of truth too narrowly. However, there are key elements of Lamarque and Olsen's theory that come very close to a Gadamerian view of art but cannot be satisfactorily explained by appealing only to the fundamental tenets of their strand of analytic philosophy. I conclude by opposing their theory insofar as it is a no-truth theory of literature, but by supporting their theory insofar as it reiterates certain insights that are provided by Gadamer. / Graduate / 0422 / adellazazzera@gmail.com

Cretaceous continental extension was accommodated by the development of the Paparoa Metamorphic Core Complex, resulting in the separation of New Zealand from Gondwana. High grade (Lower Plate) and low grade (Upper Plate) rocks are separated by the Ohika and Pike Detachment Faults. The two detachment faults have distinctly different histories, with greater exhumation along the Pike Detachment Fault. The onset of crustal extension is proposed to have commenced along the Pike Detachment Fault at 116.2 ± 5.9 Ma (Rb/Sr dating). Both geochemical and geochronological approaches are adopted for this thesis, through the in situ analysis of oxygen and hafnium isotope ratios, trace metals and U-Pb content. Chemical changes are tracked during the petrogenesis of the Buckland Granite, with mafic replenishment observed in the later stages of crystallisation. Crystallisation temperatures of the Buckland Granite are calculated using zircon saturation thermometry, with an average Ti-in-zircon temperature of 697℃ (upper-amphibolite facies). Inherited zircons in Lower Plate rocks show distinct age peaks at c. 1000, 600 and 300 Ma, illustrating the incorporation of heterogeneous local crust (Greenland Group and Karamea Batholith). Model ages (TDM) are calculated for inherited zircons of the Lower Plate rocks, which record the time at which magma bodies (zircon host rocks) were extracted from the mantle. Maximum and minimum model ages for the Buckland Granite average at 3410 Ma and 2969 Ma, with the maximum TDM value of 3410 Ma coinciding with the proposed major crustal formation event of the Gondwana supercontinent at c. 3.4-3.5 Ga. Two distinct U-Pb zircon age peaks are observed in the Buckland Granite at 102.4 ± 0.7 and 110.3 ± 0.9 Ma. The 110.3 ± 0.9 Ma age is interpreted as the crystallisation age of the pluton, while the 102.4 ± 0.7 is proposed to represent a younger thermal (magmatic?) event associated with the 101-102 Ma Stitts Tuff.

Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 52-53). Also available on the World Wide Web.

Thesis (Ph. D.)--University of Wyoming, 2007. / Title from PDF title page (viewed on June 16, 2008). Includes bibliographical references.