FK analysis of two components raw data (Vertical and H-East) in deep interval 1390 m TVD (mid-Argovien) to Total Depth 1560 m (near top Dogger): Direct P-down and PS-down are clearly present up to 170 Hz, reflected P-up arrivals are present mostly on the East component, with weak amplitude above 100 Hz. Residual aliased tube waves still appear above 100 Hz, close to sound velocity in water (1500 m/s), in spite of all efforts accomplished on the field to reduce their energy. Figure modified from Figure 3.3.2 of Bailey [8].