I have found in the literature plant impressions from unit 6 of a carbonate
lens in the lower Navajo.
"Two plant impressions were found in rocks of unit 6. the better
preserved is most likely an early reed-like form comparable to the
present-day Equisetum. it is 14.5 cm long and 0.9 cm wide at the bottom and
decreases to approximately 0.7 cm wide toward the top. The oil-like top is
not well defined, but small ridges on the outside wall of the stem are
preserved. The other impression, less well preserved, is thought to
represent a similar plant. it measures approximately 32 cm long, is 3.2 cem
wide and 1 cm deep, but has no distinctive detailed structure."~James K.
Gilland, "Paleoenvironment of a Carbonate Lens in the Lower Navajo Sandstone
Near Moab, Utah" Utah Geology 6(1979):1:29-38, p. 36
>"... ONly root casts and burrows are locally abundant in
>>some dry interdune deposits or on deflationary interdune surfaces
>>(first-order bounding surface).
>
>Root casts are defined here as burrow-like structures that could be roots,
>rather than root-like structures that contain the remains of fossil roots,
>I imagine. What is the data that suggest they are indeed remains of roots,
>other than their shape, which we have already discussed under a different
>topic?
Well, if there are leaf impressions in the Navajo, one would presume that
the leaves would need roots. And if there were plants having roots, then
rhizoliths are not to be unexpected. The intepretation is internally consistent.
I might point out that the geochemistry of this carbonate lens is such that
it precludes this being a marine deposit.
"The carbonate lens is interpreted to be a fresh water lake deposit.
Boron values are so low as to preclude possibility of marine deposition."
~James K. Gilland, "Paleoenvironment of a Carbonate Lens in the Lower Navajo
Sandstone Near Moab, Utah" Utah Geology 6(1979):1:29-38, p. 37
Also pollen and spores are quite abundant in some layers suggesting local flora
"Pollen and spores are well preserved in some layers of unit 6. A major
percentage of the specimens are of one type and give strong support to local
floral development near shore."~James K. Gilland, "Paleoenvironment of a
Carbonate Lens in the Lower Navajo Sandstone Near Moab, Utah" Utah Geology
6(1979):1:29-38, p. 36
>
>
>Of the seven localities in the Navajo
>>Sandstone now known to have produced body fossils of terrestrial
>>vertebrates, three are associated directly with interdune deposits.
>
>But did these "interdune" deposits have plant fossils in them???
>
At least one did!!!! Gotcha :-)
glenn
Adam, Apes, and Anthropology: Finding the Soul of Fossil Man
and
Foundation, Fall and Flood
http://www.isource.net/~grmorton/dmd.htm