Subduction driven processes in Costa Rica led to the development of volcanism, forming the active Central Costa Rican Volcanic Front (CCRVF). Located at the southernmost tip of the CCRVF is the active twin volcanic system, the Irazú-Turrialba Volcanic Complex (ITVC), 50 km north-east from Costa Rica's capital city, San Jose (Figure 1). The summits of each volcano are 10 km apart and form a complex that is about 60 km by 45 km at the base. To better understand these magmatic and tectonic domains, establishing the crustal structures beneath volcanic systems provides vital information into the implications of volcanism in Costa Rica.Despite being geographically close, the Irazú and Turrialba volcanoes undergo different eruptive cycles. This may partially be explained by the complex magmatic interactions between different reservoirs at depth as highlighted by geochemical and petrological data (Alvarado et al., 2006;DeVitre et al., 2019). Alvarado et al. (2006) suggest that Irazú is fed by two distinct magmatic reservoirs evolving in parallel and occasionally mixing. The