Shoreline crossing shear wave splitting across the Namibia passive margin

Understanding both the onshore and offshore components of passive margins is crucial to constrain the processes that led to continental break up as well as the dynamics that drive the present-day margin evolution. Unfortunately, margin crossing seismic datasets are a rarity. The WALPASS seismic experiment includes both on land and ocean-bottom seismic instruments traversing the passive margin off of Namibia. We present shear wave splitting measurements at the offshore and land-based stations of the WALPASS experiment. There is a change in splitting across the continent-ocean transition. On land, we see primarily plate-motion aligned fast splitting directions at both coastal and cratonic stations. Immediately offshore, splitting directions rotate to margin oblique orientations.