Teleseismic localization of velocity and quality factor: Application to Patagonia, Antarctica, D', and the whole mantle

This thesis discusses a variety of teleseismic localization techniques with application to various regions within the Earth. Two common threads continue through this thesis: (1) Differential waveform analyses produce more accurate measurements of localized anomalies than do individual waveform analyses. (2) Combining multiple data types and techniques in order to constrain the same problem yields more unique interpretations of Earth's structure, composition and dynamics.; This thesis is divided into two different aspects of teleseismic studies: (1) Joint receiver function and interstation phase velocity inversions with niching genetic algorithms provide accurate crustal and upper mantle seismic models for Patagonia and Antarctica. (2) Differential attenuation and travel-time measurements better constrain velocity and quality factor in the whole mantle than do direct attenuation and travel-time measurements.; In the scope of this thesis I develop seismic models that demonstrate variation in crustal thickness for Patagonia and Antarctica and relate the results to tectonic models. The Patagonia crustal thickness is 30 +/- 3 km having a pattern consistent with isostatic compensation. In Antarctica, the crustal thickness varies from 20--40 km under the Transantarctic Mountains (TAMs), which are a ∼4500 km long ∼4 km high mountain range that divides East and West Antarctica. Seismic velocity increases by ∼2--5% under the TAMS. The free-air gravity and bedrock topography of the Transantarctic Mountains are consistent with an elastic flexural model for mountain uplift.; This thesis also develops seismic models of quality factor and velocity, which indicate a dynamic set of processes occurring within the lowermost mantle and mantle at large. The different sensitivities of velocity and quality factor to temperature, grain size, stress, and chemical composition may be used to infer the cause for seismically imaged anomalies. The overarching pattern of high quality factor and velocity under subduction zones and large, low quality factor and low velocity zones beneath the Pacific and Africa indicate that temperature is the dominant controlling factor. However, water content in the upper mantle, stress, and grain size cannot be discounted. The pattern is consistent with cold downwelling slabs sinking into the lower mantle and warm buoyant material rising from the core-mantle boundary.