Thesis (Ph. D.)--University of Rhode Island, 2005. / Typescript. Includes bibliographical references (leaves 127-133).

Thesis (M.S.)--Oregon State University, 1987. / Typescript (photocopy). Includes bibliographical references (leaves 48-54). Also available on the World Wide Web.

The aim of this thesis is to demonstrate a design process through the creation of an architectural form as a composition of elements, material focus and locality. The desire to work with a singular material drove the project from the study of early wood working techniques to the creation of a marketplace defined by its appreciation for tectonics and the history of the local region. / Master of Architecture

The dissertation examines the interaction between basement tectonics, salt tectonics and sedimentation during the Late Cretaceous basement reactivation in the center of the Santos Basin. The study area is a seismic volume 60 x 30 km² in area, augmented by 2D regional seismic lines. The results of seismic interpretation and structural restorations revealed important inversions in the Late Cretaceous, including inversion of an NNE-oriented aborted rift segment known as Merluza Graben. The following tectono-stratigraphic evolution was inferred. During the Albian, basin subsidence and differential loading by the overburden caused salt to flow basinwards. In the Late Turonian, intraplate compression resulted in uplift of the onshore and proximal areas of the Santos Basin and in a newly recognized basement inversion in deep water. ENE and NNE oriented structures were reactivated. The uplift exposed the Turonian shelf and a new shelf began to prograde. The first shelves were narrow (~25 km wide) but enlarged to 60 km in the Santonian. Salt influenced the position of the shelf break and the progradation pattern of the shelf margin. Because of the continuous accommodation space provided by salt withdrawal underneath the sedimentary wedge, the shelf margin aggraded until underlying salt welded, after which the shelf prograded to a position around 50 km to the east of the present-day shelf break. Deformation peaked in the Late Santonian when the shelf was widest, the rate of progradation of the shelf margin was anomalously high, and transtension along the borders of the Merluza Graben allowed Late Santonian magma to intrude. Salt acted as a partial seal, causing a large part of the magma to spread beneath it. Some magma formed sills inside the evaporitic layer, intruding zones of dilation in the salt. Magma also followed the top of the evaporitic layer and intruded salt-related faults as dikes. These dikes supplied sills in the overburden and extrusive flows emerged on the Late Santonian seafloor from ENE-striking transtensional zones. Right-lateral reactivation of the Merluza Graben borders slightly compressed the graben, which favored sill injection in Coniacian/Santonian strata. Tectonic activity diminished towards the end of the Cretaceous. / text

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No description available.

Thesis (M. Sc.)--University of Canterbury, 2007. / Typescript (photocopy). Includes bibliographical references (leaves 190-202). Also available via the World Wide Web.

<p> The St. Cyr klippe hosts well preserved to variably retrogressed eclogites found as sub-meter to hundreds of meter scale lenses within quartzofeldspathic schists in the Yukon-Tanana terrane, Canadian Cordillera. The St. Cyr area consists of structurally imbricated, polydeformed, and polymetamorphosed units of continental arc and oceanic crust. The eclogite-bearing quartzofeldspathic schists form a 30 by 6 kilometer thick, northwest-striking, coherent package. The schists consist of metasediments and felsic intrusives that are intercalated on the tens of meter scale. The presence of phengite and Permian age zircon crystallized under eclogite facies metamorphic conditions indicates that the eclogite was metamorphosed <i>in situ</i> with its quartzofeldspathic host. </p><p> I investigated the metamorphic evolution of the eclogite-facies rocks in the St. Cyr klippe using isochemical phase equilibrium thermodynamic (pseudosection) modeling. I constructed <i>P-T</i> pseudosections in the system Na₂O-K₂O-CaO-FeO-O₂-MnO-MgO-Al₂O₃-SiO₂-TiO₂-H₂O for the bulk-rock composition of an eclogite and a host metatonalite. In combination with petrology and mineral compositions, St. Cyr eclogites followed a five-stage clockwise <i> P-T</i> path. Peak pressure conditions for the eclogites and metatonalites reached up to 3.2 GPa, well within the coesite stability field, indicating the eclogites reached ultrahigh-pressure conditions. Decompression during exhumation occurred with a corresponding temperature increase. </p><p> SHRIMP-RG zircon dating shows that the protolith of the eclogites formed within the Yukon-Tanana terrane during early, continental arc activity, between 364 and 380 Ma, while the metatonalite protolith formed at approximately 334 Ma, during the Little Salmon Cycle of the Klinkit phase of Yukon-Tanana arc activity. Both the eclogites and the metatonalites were then subducted to mantle depths and metamorphosed to ultrahigh-pressure conditions during the late Permian, between 266 and 271 Ma. The results of our study suggest portions of the Yukon-Tanana terrane were subducted to high-pressure and ultrahigh-pressure conditions. This is the first report of ultrahigh-pressure metamorphism in the accreted terranes of the North American Cordillera. Petrological, geochemical, geochronological, and structural relationships link the eclogites at St. Cyr to other eclogite localities in Yukon, indicating the high-pressure assemblages form a larger lithotectonic unit within the Yukon-Tanana terrane.</p>

No description available.

Sediment flux from the Alps shows a sharp increase around the Mio-Pliocene boundary (~5 Ma). This observation, linked to the exhumation of the Swiss Molasse basin since ca. 5-4 Ma has led to the suggestion that the Alps experienced accelerated exhumation and isostatic uplift at the orogen scale since this time. The core objectives of this thesis are to assess whether we can document post 5 Ma exhumation of the Alps and its spatial and temporal development, and to review the different potential (tectonic or climatic) factors controlling this denudation. I have developed a novel technique that uses isoage contours associated with age-elevation relationships to exploit the unique density of fission-track ages in the western European Alps, reconstruct cooling isoage surfaces and estimate exhumation rates on the orogen scale between 13.5 and 2.5 Ma. The exhumation histories reconstructed for eight areas of the Western Alps display strong similarities in timing and rate with orogen-wide average denudation rates inferred from sediment volumes. Exhumation rates increased more than twofold since Late Miocene times, and may have been locally modulated by the distinct response of different tectonic units. I then searched for correlation between the spatial pattern of long-term exhumation rates, from the apatite fission-track record, and potential controlling parameters. In the Western Alps, long-term exhumation rates correlate strongly with presentday rates of rock uplift, implying that the rock uplift pattern observed today is ancient. I also observed that the spatial pattern of released seismic energy does not correlate with rock uplift or exhumation, which suggests that exhumation is controlled by isostatic rebound rather than by active tectonic uplift. The lack of correlation between exhumation rates and the presentday distribution of precipitation suggests that the present-day pattern is either non representative of the long-term trend or that factors other than precipitation rate dominate the intensity of exhumation. In order to study the exhumation history in more detail, I sampled two elevation profiles in the central Aar massif (Switzerland) and the western Lepontine Alps (Italy) for AFT and AHe dating which are characterised by steep age-elevation relationships around 8 and 4 Ma. I used the Pecube model to predict AFT and AHe ages according to several tens of exhumation scenarios and compared modeled and measured ages. The results of numerical modeling do not reject the hypothesis of two exhumation pulses at 9-7 and 5-3 Ma in the Aar massif. However, this signal is not detected in the Lepontine Alps, and contingent upon further flexural modeling, the exhumation recorded in the Aar massif since 5 Ma does not match the amount required to explain the denudation in the Swiss Molasse basin by flexural isostatic rebound. Rather, the data hint at an additional mechanism of rock uplift, such as the delamination of lithospheric mantle.