Shown below is a channelled incision surface developed within an offshore mudstone facies. Overlying facies are somewhat siltier and contain evidence of tidal influence. Large dolomite-cemented bodies are also associated with the channelled surface. The channel itself can be traced for at least one mile. This photography was taken in the Cretaceous Mancos Shale near Woodside, Utah. Diane Kamola (University of Kansas) is pointing to the erosion surface.
Shown below is a bevelled erosional surface showing obvious truncation of underlying strata. At the scale of this entire outcrop, it can be shown that the underlying strata were deformed into a monocline prior to truncation. Photograph taken in the Mississippian Bangor Limestone along I-24 southeast of Monteagle, Tennessee.
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