In November 2001 a network of reflection profiles utilizing airgun sources was shot using the RV Sonne across the continental margin of southern Chile, in the vicinity of the source region of the 1960 earthquake. Utilizing onshore recordings of the airgun sources and additional onshore and offshore sources, a combined onshore-offshore, active-passive seismic project between 36°S and 39°S was realized. This project comprised i) a pilot near-vertical incidence reflection (NVR) seismic experiment covering the onshore-offshore transition along an E-W line at 38°15´S, ii) three consecutive E-W wide-angle reflection / refraction (WRR) lines at 36°20´S (SPOC-North), 37°15´S (SPOC-Middle) and 38°15´S (SPOC-South), iii) an array of 30 stations for recording both active and passive sources and iv) six broadband stations along a profile at 39°S. The pilot NVR experiment at 38°15´S covers the near-shore part of the subduction zone between the South American and Nazca plates. The main aim of the experiment was to test the structural and reflectivity potential along the seismogenic plate interface. From the WRR experiments, three 2-D velocity models for the crust and uppermost mantle across the forearc region of southern Chile were obtained.