A simple, half-space elastic model is used to investigate interseismic strain accumulation above a subduction zone associated with oblique plate convergence. The horizontal surface velocity field near the leading edge of the upper plate is found to rotate as distance from the trench increases. Above the locked portion of the plate interface, surface velocity is more oblique than the plate convergence vector. Farther back, toward the interior of the upper plate, the surface velocity is less oblique than the plate convergence vector. Surface velocity fields emphasize the strike-slip component of plate convergence near the locked zone and emphasize the dip-slip component farther back. This interseismic 'strain partitioning' is purely elastic: interseismic straining will be reversed during the eventual rupture of the locked zone.