Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 19 of 19 for “"Lithospheric structure."”.
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Lithospheric Structure Across the Northern Canadian Cordillera from Teleseismic Receiver Functions
… an important role in characterizing the overall structure of the crust and can be related to the tectonic setting of a region. Teleseismic P-wave receiver function techniques can provide estimates of the depth of the Moho and therefore crustal thickness under a broadband station. In this research …
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Marine geophysical applications of seasat altimetry and the lithospheric structure of the South Atlantic Ocean
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1987.
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The origin and tectonic history of the Southwest Philippine Sea
… associated with this spreading by nature of its structure and trend, and it may be a remanent of a former ridge system. Our preliminary calculation of paleopole positions also suggests that there was a large amount (60°) of clockwise rotation between this basin and the magnetic pole. This is …
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Seismic and numerical constraints on the formation and evolution of oceanic lithosphere
This thesis explicates aspects of the basic structure of oceanic lithosphere that are shaped by the processes that form the lithosphere. The strength of lithospheric plates relative to the underlying mantle enables the surface plate motions and plate boundary processes that characterize plate …
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Seismic and numerical constraints on the formation and evolution of ocean lithosphere
This thesis explicates aspects of the basic structure of oceanic lithosphere that are shaped by the processes that form the lithosphere. The strength of lithospheric plates relative to the underlying mantle enables the surface plate motions and plate boundary processes that characterize plate …
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THE SEDIMENT AND CRUSTAL STRUCTURE OF THE SOUTHEASTERN UNITED STATES
… function technique, enable detailed imaging of lithospheric structure, but suffer from contamination in sedimented regions. Therefore, I implement a method for constraining average crustal thickness and seismic velocities while correcting for the effects of sediments. I then use high-frequency …
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Characterizing the southeast Caribbean-South American plate boundary at 64°W
The crustal and lithospheric structure of the northern South America plate boundary with the southeast Caribbean has been the focus of many studies. In this region, westward subduction of (Atlantic) oceanic South America transitions to east-west transform between continental South America and the …
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Pluton source varition over two magmatic pulses in the White-Inyo range, central-eastern California : implications for paleozoic and mesozoic tectonic reconstructions
… goal of this dissertation is to understand the lithospheric structure of this area in relation to the broader regional tectonics. Chapters 2 and 3 specifically investigate the Eureka Valley-Joshua Flat-Beer Creek (EJB) composite arc pluton, from its source to emplacement. The EJB pluton is one …
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Teleseismic imaging of the Slave craton and implications for the assembly of cratonic lithosphere
… complementary seismological methods to image the lithospheric structure of the Slave craton in Canada. First, I perform surface wave tomographic inversions to constrain the depth dependence of Rayleigh wave phase velocity, shear wave velocity, and azimuthal anisotropy of the Slave cratonic …
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Geophysical and petrological constraints on ocean plate dynamics
… the formation and subsequent motion of oceanic lithospheric plates through geophysical and petrological methods. Ocean crust and lithosphere forms at mid-ocean ridges as the underlying asthenosphere rises, melts, and flows away from the ridge axis. In Chapters 2 and 3, I present the results from …
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Geophysical and petrological constraints on ocean plate dynamics
… the formation and subsequent motion of oceanic lithospheric plates through geophysical and petrological methods. Ocean crust and lithosphere forms at mid-ocean ridges as the underlying asthenosphere rises, melts, and flows away from the ridge axis. In Chapters 2 and 3, I present the results from …
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Finite-element modeling of large impact craters: Implications for the size of the Vredefort structure and the formation of multiple ring craters
… are large terrestrial craters whose sub-surface structures can be studied, most have been modified by subsequent geologic activity. Laboratory experiments are necessarily limited to very small impacts so their results need to be extrapolated over many orders of magnitude to compare to the largest …
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Seismic imaging of the western Hellenic subduction zone : the relationship between slab composition, retreat rate, and overriding lithosphere genesis
In this dissertation, I investigate the structure and dynamics of the Western Hellenic Subduction Zone (WHSZ) by using two complementary seismic imaging methods and interpreting the resulting images with models that describe the dynamics of retreating subduction. First, I produce high-resolution …
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Observations of Dynamic Topography from South American Atlantic Margin
… Earth is mainly controlled by its crustal and lithospheric architecture. Variations in thickness and density of the crust and of the lithospheric mantle create the most noticeable topography. However, it is also widely recognized that mantle convective processes dynamically support topography …
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A Geodynamic Investigation of Magma-Poor Rifting Processes and Melt Generation: A Case Study of the Malawi Rift and Rungwe Volcanic Province, East Africa
… tip of the Malawi Rift. In chapter 1, we use the lithospheric structure of the Malawi Rift derived from the World Gravity Model 2012 to constrain three-dimensional (3D) numerical models of lithosphere-asthenosphere interactions, which indicate ~3 cm/yr asthenospheric upwelling beneath the thin …
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Heterogeneous Strain Distribution & the Effects of High Frequency Climate Change on the Evolution of Early-Stage Rift Systems: Case Studies from Lakes Tanganyika and Malawi (Nyasa), East Africa
… within the earth’s crust such as pre-existing structures. Such inhomogeneities from earlier rift or orogenic events can assist in weakening and stretching the earth’s crust. While extensional faulting drives continental rifting, changes in the relief of the landscape, erosion of different …
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Plio-pleistocene tectonic evolution of Southern Sardinia
… to now there are not detailed studies about the structures and the kinematic related to the Plio-Pleistocene tectonics in southern Sardinia, although tectonic activity during the latest million years is long since known in the Island. Then, the general aim of this research is to improve the …
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Ambient seismic noise tomography of the southern United States and seismic inversion with dictionary learning using unsupervised machine learning.
… methods to understand deep subsurface structures. These techniques are particularly effective in delineating complex crustal architectures, which often deviate from simplified textbook models. High-resolution seismic tomography enables the interpretation of such intricate geological …