This deployment is an ambitious supplement to the Langseth offshore Cascadia survey scheduled for the summer of 2020. The focus of the onshore nodal deployment will be extending the ~20 2-D trench perpendicular offshore seismic lines ~50 km inland along the entire margin. Emerging work in subduction zones shows the controlled offshore source is well recorded on onshore receivers. Thus, we intend to leverage the scheduled Langseth survey to image the complete trench to wedge structure of multiple segments along the margin. A few, perhaps three or four 2-D lines will be extended further into the arc setting to investigate the along-strike variability observed in Cascadia using passive source techniques.