Plain language summary
Topographic growth and morphology of the Andes have been strongly influenced by subduction processes, tectonic inheritance, and climate. Here, we investigate the role of subduction of bathymetric highs in driving continental plate deformation at ocean-continent plate margins. The subduction of the Carnegie Ridge, a linear bathymetric high on the subducting Nazca Plate in the Eastern Pacific, has strongly impacted magmatism and tectonic activity in the Ecuadorian Andes. We employed radioisotopic dating techniques and numerical modeling to evaluate the uplift of Andes by exploiting information contained in certain minerals that record the cooling of rock as mountain ranges are uplifted, and eroded. The cooling histories of rocks from the Western Cordillera in Ecuador reveal two distinct phases of cooling. The first phase of cooling occurred shortly after magmatic bodies were emplaced in the Western Cordillera. The second phase began after 6 Ma, which we attribute to the onset of uplift and erosion in the Western Cordillera, coeval with the last cooling phase in the Eastern Cordillera. Based on these findings we suggest that the onset of subduction of the Carnegie Ridge increased the coupling between the two plates and promoted shortening and regional rock uplift in this part of the Andes.