Figure 13. Lifestyle modes of diatom assemblages on Microfacies 2 sinter. (1) Clusters of diatoms occupying numerous portions of a spicule. (2) Cluster of diatoms occupying a crevice on a spicule surface. (3) Diatoms wedged along layers of silica that act as surfaces of positive relief. Note the succession of silica layers that drape a spicule surface (red arrows), forming convex-upward layers similar to those observed in thin section (Figure 11.1). (4) Diatoms closely appressed to the surface by a coating of mucosal EPS. (5) Fractured diatom cells amassed together in an open area lacking shelter by surrounding sinter. (6) Cemented diatom cells incorporated into sinter.