Figure F7. Pictured on the left is a core photograph with sample intervals and scale as in Figure F3. Stars highlight intervals corresponding to photomicrographs on the right (all in plane-polarized light except C, which is with nicols crossed). A. Wispy to peletal texture in organic-rich chert. White areas are distorted (compacted) radiolarians infilled by chalcedony. B. Bioturbated contact between organic-rich porcellanite (light) and organic-rich shale (dark). Note discrete burrows in porcellanite infilled by organic-rich shale (circled in photomicrograph) and similar distribution of radiolarians (white circular features) throughout both lithologies. C. Radiolarian sparite. Circular features are radiolarians completely infilled and enveloped by large poikilotopic calcite crystals (relative extinction marked by shades of gray). D. Close-up of radial bioturbation textures (tan linear streaks) in organic-rich shale.