--> Figure 2. Core photo of prodelta facies of the Cretaceous Dunvegan Formation, showing both inverse and normally graded siltstones. Wispy mud-streaks at 4.5 cm (1.8 in) are identified as Phycosiphon(Ph). Note that these lie in the clayey tops of thick graded siltstone beds, and may reflect colonization of the bed top after deposition. Lateral disruption of sandy and silty laminae may represent “mantle and swirl” (ms) structures, recording the activity of sediment-swimming organisms in the rather soupy substrate. Small flame structures in upper units also indicate soft-sediment deformation. Unlabeled Planolites (P) occurs on the right side of the photo, and marked on the litholog.

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Figure 2. Core photo of prodelta facies of the Cretaceous Dunvegan Formation, showing both inverse and normally graded siltstones. Wispy mud-streaks at 4.5 cm (1.8 in) are identified as Phycosiphon(Ph). Note that these lie in the clayey tops of thick graded siltstone beds, and may reflect colonization of the bed top after deposition. Lateral disruption of sandy and silty laminae may represent “mantle and swirl” (ms) structures, recording the activity of sediment-swimming organisms in the rather soupy substrate. Small flame structures in upper units also indicate soft-sediment deformation. Unlabeled Planolites (P) occurs on the right side of the photo, and marked on the litholog.