Skeletal limestone lenses filling scours within Lake Neosho Shale
The contact between the phosphatic shale and bioclastic
shale occurs at
the color change from dark gray to greenish gray. Reddish brown streaks
below the contact are phosphate nodules and laminae stained by iron oxide.
White specks above the contact are fossil fragments, and the white lenses
protruding downward into the dark shale are limestone composed of fossil
debris. These were deposited in current-scoured depressions on the contact.
Currents were strong enough to sweep away finer sediment, leaving only
the fossils. Note that strata underlying the left lens conform to the shape of
the scoured surface--the phosphatic stringer was pushed down beneath the
lens. This is a compactional feature.
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