Investigations of Earthquake Source Processes Based on Fault Models with Variable Friction Rheology

First and foremost, I would like to express my sincere gratitude to my advisor Nadia Lapusta, for all her support, patience, and guidance during the course of my graduate study. Nadia is always willing to spend hours with me on discussing my research, and has always taken extremely good care of me and other students. I also deeply appreciate her support while allowing me to pursue my ideas in the middle of my PhD. I would like to thank all other members of my committee, Jean-Philippe Avouac, Pablo Ampuero, Tom Heaton, and Rob Clayton for reviewing my thesis and providing valuable suggestions and criticism. I am especially grateful to Jean-Philippe and Pablo for our research collaboration that resulted in parts of this thesis. The research with Jean-Philippe originated from his well-taught reading course (Ge 277) that motivated me to explain observations of seismic and aseismic slip. I have greatly benefited from discussions about earthquake physics with Tom Heaton. Rob Clayton has been a very good academic advisor. Discussions with and lectures of Nadia Lapusta, Hiroo Kanamori, Jeroen Tromp, Don Helmberger, Mark Simons, Rob Clayton, and Mike Gurnis have taught me a lot both about scientific subjects and about ways to investigate them. I thank them for sharing their knowledge and insight with me. My sincere appreciation extends to my current and former colleagues. It has been aiv