Graduation Year


Document Type




Degree Name

Doctor of Philosophy (Ph.D.)

Degree Granting Department


Major Professor

Timothy H. Dixon, Ph.D.

Co-Major Professor

Rocco Malservisi, Ph.D.

Committee Member

Charles B. Connor, Ph.D.

Committee Member

Sarah Kruse, Ph.D.

Committee Member

Susan Schwartz, Ph.D.


Episodic Tremor and Slip, geodesy, natural hazards, GPS time series


Slow Slip Events (SSEs) represent a new type of strain release along faults, which have onlybeen recognized as a global phenomena with the growth of precision space-borne geodetic techniques. These events represent an important part of the strain budget on faults, sometimes bounding the area of co-seismic release and perhaps limiting the amount of seismic energy release. SSEs have also been suggested to proceed large megathrust earthquakes including the great 2011 Tohoku and 2015 Iquique earthquakes. I document a series of SSE along the Nicoya Peninsula in Costa Rica. These events take place both before and after the 2012 M7.6 Nicoya earthquake, and bound the earthquake rupture. I also document a precursor SSE prior to the 2012 earthquake, which ruptures into the locked co-seismic region in the days leading up to the seismic rupture. These observations highlight the importance of SSEs in the seismic cycle. I discuss their importance in the context of seismic hazard and the variability that limits their predictive importance. Finally, I discuss some new approaches to more accurately characterize the time-dependent history of GPS displacement time series.