Figure 7. Associated trace fossils and bioturbate textures. Ribbed tubes with well-developed, laminated fill often co-occur with the horizontal, regularly-oriented structures ( 1 – field view; 2 - 3 - close ups). Note the well-developed boxwork of tubes in 1, and the rectangle that shows the sample enlarged in 2 - 3. In 2, the white arrows highlight the ribbed surface of the tubes. 4 - 5 ) Negative epirelief of randomly oriented traces, which have similar diameters and distributions as the ribbed tubes with laminated fill. These might represent another trace fossil type, but they could also be preservational variations of the ribbed tubes. For a positive epirelief image, rotate the figure 180º.