Investigation of the Effects of Nazca-South America Plate Collision along the Peruvian-Chilean Active Continental Margin through Teleseismic Receiver Function Analysis

In this dissertation I present the results of three studies examining the Peruvian-Chilean Trench and Andes Mountains along the western margin of South America. Two studies focus on the southern end of the Peruvian flat slab (where the subducting Nazca oceanic plate descends at an angle of ~30° before flattening near 80 km to 100 km depth) and its effects on the overriding plate. The third study focuses on normal subduction (where the subducting Nazca oceanic plate descends continuously at an angle ~30°) in the Maule region of central Chile where I look at the Chile forearc associated with the Mw=8.8 2010 Maule earthquake. In all three studies I draw attention to similarities and contrasts between my observations of these regions and previous studies from similar tectonic settings. The first study uses teleseismic receiver functions to image the Mohos of the subducting Nazca oceanic plate and of the overriding South America continental plate. From these observations, I calculate and map surfaces representing the Moho of each plate to better understand their interactions. I find that the overthickened crust of the subducting Nazca Ridge forms the shallowest part of the southern segment of the Peruvian flat slab and lies at