Graduation Year
2023
Document Type
Thesis
Degree
M.S.
Degree Name
Master of Science (M.S.)
Degree Granting Department
School of Geosciences
Major Professor
Timothy H. Dixon, Ph.D.
Co-Major Professor
Rocco Malservisi, Ph.D.
Committee Member
Jochen Braunmiller, Ph.D.
Keywords
Velocity Structure, Central Alborz, Slow Slip Event, Earthquake triggering, Costa Rica
Abstract
Being a part of a seismically active zone, including large and crowded cities such asTehran, Qazvin and Semnan, Central Alborz experiences many local earthquakes. Knowl- edge of crustal velocity structure in this area is thus necessary considering its economical and political importance, a large concentration of population, and relatively poor construc- tion practice which increases the earthquake risks in this region. In second chapter of this thesis, we aim at obtaining the 3D crustal velocity structure of the Central Alborz region in northern Iran using local earthquake tomography. We also validate anomalies inferred from our velocity model using an independent gravity modeling and investigate that the gravity and tomographic results are in good agreement.
The Nicoya Peninsula of Costa Rica, where the Cocos plate subducts beneath the Caribbean plate along the Middle American Trench, is a good location to study the interaction between Slow Slip Events (SSEs) and megathrust earthquakes. SSEs beneath the Nicoya Peninsula have been recorded both updip and downdip of the seismogenic zone with recurrence times of about 22 months, and large earthquakes (M >7) occur approximately every 50–60 years. In chapter three, using GPS observations, we conduct a study to describe SSEs that occurred in 2015, 2017 and 2019 on the Nicoya Peninsula of Costa Rica. The SSE in 2017 coincided with November 13 M w 6.5 Costa Rica earthquake, southeast of the slipping area. We investigate possible triggering relation between the two events. In this thesis, I will show some examples of applications of seismic and geodetic data in earthquake hazard studies.
Scholar Commons Citation
Afra, Mahsa, "Applications of Seismic and Geodetic Data to Earthquake Hazard Research" (2023). USF Tampa Graduate Theses and Dissertations.
https://digitalcommons.usf.edu/etd/9952
