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Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

Geological Structures And Crustal Architecture Of The Cascadia Subduction Zone From The Integration Of Multiple Geophysical Datasets, Asif Ashraf Jul 2021

Geological Structures And Crustal Architecture Of The Cascadia Subduction Zone From The Integration Of Multiple Geophysical Datasets, Asif Ashraf

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The Cascadia subduction zone (CSZ) has a high potential for an inevitable and devastating megathrust earthquake. This margin is characterized by a complex seismicity pattern. Particularly in Oregon, there is a seismically quiescent zone bounded by high seismicity regions to the north and south. To comprehend these variations in seismicity, it is important to study the differences in crustal architectures and physical properties (densities and magnetic susceptibilities) along the CSZ. The primary objectives are to develop two plate-scale 2D integrated models through different seismicity zones and to map major tectonic structures from filtered potential fields. The Juan de Fuca oceanic …


Drone-Based Magnetic Surveying In Eastern Nebraska, Sulaiman Albadi Jun 2021

Drone-Based Magnetic Surveying In Eastern Nebraska, Sulaiman Albadi

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

A magnetic survey is one of the methods used by scientists to detect subsurface features. Magnetic surveys can be carried out by walking on the surface of the earth with a magnetic field reading device called a magnetometer. Alternatively, a magnetometer can be installed on a moving platform (aircraft, boat, drone, bicycle) to conduct a more efficient magnetic survey. The geophysics team at the University of Nebraska at Lincoln assembled a drone-based magnetic survey system in 2019 (Jacobson and Filina, 2019) that has proven effective in magnetic readings over the Northern Bounding Fault (NBF) in eastern Nebraska (Jacobson and Filina, …


Inference Of Surface Velocities From Oblique Time Lapse Photos And Terrestrial Based Lidar At The Helheim Glacier, Franklyn T. Dunbar Ii Jan 2021

Inference Of Surface Velocities From Oblique Time Lapse Photos And Terrestrial Based Lidar At The Helheim Glacier, Franklyn T. Dunbar Ii

Graduate Student Theses, Dissertations, & Professional Papers

Using time dependent observations derived from terrestrial LiDAR and oblique
time-lapse imagery, we demonstrate that a Bayesian approach to glacial motion es-
timation provides a concise way to incorporate multiple data products into a single
motion estimation procedure effectively producing surface velocity estimates with
an associated uncertainty. This approach brings both improved computational effi-
ciency, and greater scalability across observational time-frames when compared to
existing methods. To gauge efficacy, we apply these methods to a set of observa-
tions from the Helheim Glacier, a critical actor in contemporary mass loss trends
observed in the Greenland Ice Sheet. We find that …