Figure 3a.  Peak acceleration, velocity and displacement of the radial component of motion versus normalized epicentral distance, R/W1/3. The lines represent the least squares fit through the data points. The stations are separated in two groups depending on whether the R-axis is parallel (open squares) or perpendicular (solid squares) to the explosion rows. The dashed and solid lines represent the respective least squares fits through the data points. Explosion-station pairs are indicated for selected tests.