Profile
of Pierre shale. The thin light colored band at the top under the plant
roots is bentonite, a weathering product of volcanic ash. (Location is
1 mile northeast of Oacoma in Lyman county).
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Profile
of Pierre shale. The thin light colored band at the top under the plant
roots is bentonite, a weathering product of volcanic ash. (Location is
1 mile northeast of Oacoma in Lyman county).
|
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