The Clip Soundings operation simply removes some of the data from the top and bottom of all profiles. In the example above the portions shaded red will be clipped. In the Operation window on top of the horizontal o-scope (wiggle) view, use the left mouse button to drag the shaded area to the right to clip some of the data from the top. Notice that the clipped area is also shown on the profile below. This should be used to set the depth for time zero, or the position in the profile/trace that best represents the ground surface. Use the right mouse buttom to set the lower limit in the same manner. Clipping unneeded portions at the bottom of profiles reduces file size.