Earthquake Source Characterization Using 3D Numerical Modeling

• Main Author: Hjörleifsdóttir, Vala
• Format: Thesis
• Language: English
• Published: California Institute of Technology 2007
• Subjects: Kunlun; Sumatra; Geophysics; FOS Earth and related environmental sciences; Kokoxilli; Bhuj; Balleny Islands
• Online Access: https://dx.doi.org/10.7907/m17s-7w40; https://resolver.caltech.edu/CaltechETD:etd-03212007-170259

To understand the physics of earthquakes, it is important to know what happens during individual events. Dissembling the information about the source process from the recorded seismograms is a difficult and non-unique process, as there are severe trade-offs between many of the source parameters. In this thesis we attempt to add information from frequencies not used during the initial modeling of individual events to put more constraints on the source process, to learn about specific source parameters important to the physics of earthquakes. We model earthquakes using a spectral element method for wave-propagation that accurately accounts for the Earth's 3D elastic structure. We study the rupture speed of the 2001 Kunlun, China earthquake, the continuity of slip during the 1998 Balleny Islands event and the duration of slip during the 2004 Sumatra-Andaman, Indonesia earthquake. Finally, we explore the feasibility of using adjoint methods to learn about the earthquake source.