Figure 2A -- Offset limited fold plot for narrow-azimuth design A. These figures show a magnified portion of the fold plot that results when source-to-detector offsets are limited to 0 to 5,000 feet. Individual cells or subsurface bins are delineated as squares. Trace count in any given cell is indicated by both the color and number within each square. Offset limited fold for this design is much higher than designs B or C, and ranges from 10 to 14.