This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The proposed work is to examine changes in structural and physical properties along the southern Costa Rica subduction zone using 3D seismic imaging. At this location the plate boundary transitions from stable sliding to unstable sliding. Understanding subduction zone processes is important for assessing geologic hazards such as earthquakes and tsunamis in these environments. In the proposed work, seismically imaged structures will be used to address several fundamental problems such as 1) the structure and nature of large sediment lenses that are being subducted; b) the effects of existing seafloor topography on subduction processes; c) the changes in plate boundary fault geometry along the trench; and d) the variations in the structure of the upper plate along the subduction zone. This work will support the education and training of graduate students. There is international collaboration with scientists from Spain, Germany and Costa Rica. There is also a component of industry support.
