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Geophysics and Seismology Commons

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Full-Text Articles in Geophysics and Seismology

Surface Morphology And Subsurface Ice Content Relationships In Arcadia Planitia, Mars And The Canadian High Arctic, Shannon M. Hibbard Aug 2021

Surface Morphology And Subsurface Ice Content Relationships In Arcadia Planitia, Mars And The Canadian High Arctic, Shannon M. Hibbard

Electronic Thesis and Dissertation Repository

As NASA and SpaceX prepare for future human missions to Mars as part of an In-situ Resource Utilization (ISRU) Space Act Agreement (SAA), we need more detailed characterization of ice at proposed landing sites to constrain ice accessibility, landing safety, and scientific value. Obtaining near-surface in situ water-ice can be used for rocket fuel and life support needs which would significantly reduce the mass needed for transport to and from Mars. Arcadia Planitia is the lowest-lying region in the northern hemisphere of Mars where abundant evidence exists for an ice-rich subsurface. Shallow Radar observations indicate a decameters-thick layer of water-ice …


Stochastic Source Modelling And Tsunami Analysis Of The 2012 Mw 7.8 Haida Gwaii Earthquake, Karina Martinez Alcala Aug 2021

Stochastic Source Modelling And Tsunami Analysis Of The 2012 Mw 7.8 Haida Gwaii Earthquake, Karina Martinez Alcala

Electronic Thesis and Dissertation Repository

The Mw 7.8 2012 Haida Gwaii Earthquake triggered a tsunami that highlighted the importance of tsunami hazard assessment on Canada’s Pacific coast. Stochastic source modelling serves as a valuable method to assess future tsunami hazard and has not been performed for this region. The source models characterize the uncertainty of earthquake ruptures by considering variability in fault geometry and slip heterogeneity, which, in turn, allows the consideration of a wide range of tsunami scenarios in the Haida Gwaii region. The model predictions are constrained by observational data and past source inversion studies. One hundred twenty-eight stochastic tsunami scenarios are generated …


A Transformer-Based Classification System For Volcanic Seismic Signals, Cristian Bravo Roman, Cindy Mora Stock, Alexander James Hemming Aug 2021

A Transformer-Based Classification System For Volcanic Seismic Signals, Cristian Bravo Roman, Cindy Mora Stock, Alexander James Hemming

Undergraduate Student Research Internships Conference

Volcanic seismic signals are a key element in volcano monitoring to assess the state of unrest and a possible eruption style and timing. Different sources such as brittle fracture (volcano-tectonic - VT) or fluid movement (long period - LP) generate signals with distinct characteristics in frequency content and shape, but site effects such as attenuation or background noise make their determination difficult to the untrained eye. In cases of unrest or an eminent eruption, the amount of data would require a fast and reliable source of pre-classification to classify and catalogue to aid in the job usually done by a …


Seismic Imaging In Crystalline Terrains Of The Superior Province, Canada, Brian Villamizar Jul 2021

Seismic Imaging In Crystalline Terrains Of The Superior Province, Canada, Brian Villamizar

Electronic Thesis and Dissertation Repository

The imaging of structures in sedimentary basins has typically been carried out using conventional seismic reflection techniques. In complex geological architectures, such as those within the Superior Province in Canada, conventional seismic imaging yields suboptimal results due to factors stemming from complex energy scattering and crooked seismic geometries. Full-waveform inversion (FWI) is a nonlinear inverse technique capable of retrieving quantitative images of velocity structures. Judicious data preconditioning, and multiscale inversion strategies allow FWI to effectively estimate velocity variations in the first few kilometers of the subsurface. Non-conventional seismic reflection processing, based on azimuthal binning and enhanced migration velocity models, improves …