This paper describes surface wave waveforms observed at the Saudi Arabian Seismic Network. We identify records corresponding to events occuring in the Kuril Islands region as anomalous and discuss possible causes for the waveform distortions. Most likely, the waveform anomalies are caused by constructive and destructive interference of laterally refracted wave packets. Some waveform anomalies are probably of instrumental origin and we suspect a calibration error for the vertical component at station RIYD. For station AFIF, we find a significant clockwise rotation of the horizontal components with respect to geographic North by approximately 4 degrees. ¿ 2001 American Geophysical Union