Collaborative Research: Seismogenesis of the Middle America Trench at the Nicoya Peninsula over multiple seismic cycles

Virginia Polytechnic Institute And State University, Blacksburg VA

Investigators

Abstract

Intellectual Merit The proposed work would use onshore geologic evidence from the Nicoya Peninsula to address basic questions related to subduction along a 100-km-long part of the Middle America Trench. The work includes the following components: (1) Paleoseismology: This part of the project will investigate pre-historic earthquake size and recurrence using the stratigraphy and paleoecology of an estuary. (2) Paleogeodesy: As part of the paleoseismic investigation, the study would investigate relative sea level change on the Nicoya Peninsula to assess patterns of vertical ground motion during intervals between earthquakes. (3) Morphotectonics and long-term uplift: The study will test the relationship of long-term deformation to earthquake generation. All of these techniques will be combined to define the pre-historic rupture behavior along the subduction zone. Broader Impacts This project includes the training of a Ph.D. student. Undergraduate students will participate in the field program. There is a large component of international collaboration with colleagues in Costa Rica. A workshop for students from the US and Costa Rica will be organized, and a field school for the students will be held at the research site. The study is important for understanding seismic hazards in Costa Rica.