MARION COUNTY, Miss. (WJTV) – Red Bluff in Mississippi is about the best-known example of exposed layers of the past anywhere in the state. Hikers stroll today on what’s left of a section of Highway 587 between Foxworth and Monticello, which used to run past Red Bluff.
Red Bluff undermined the old roadway again. Crews put the latest new road a quarter of a mile over the hill, so we’re safe for a while, but Red Bluff will eventually get to it, too.
I wonder how long ago it started; the erosion that’s has washed half a hillside down into the nearby Pearl River and eventually on out to the Gulf of Mexico. The onion layers revealed by the washout are segments of sand, gravel and clay of various hues and textures. I’m not a geologist, but I know a few. I know that sand and gravel hints of flowing water or rivers, and clay is formed by water sitting for a long, long time as the minerals dissolve out of it and settle into a layer.
A lot of moving and standing water formed the layers of Red Bluff, and they tell of an entirely different geology over Mississippi back then than the rolling hills and pine trees we are used to. Even at the top of the bluff, which is more than 300 feet above sea level there, were rivers. At the lower levels, where the clay deposits are, flat broad deltas where the rivers once widened as they neared the coast. Yes, this far inland.
All of that written between the lines; the lines of discrete layers of soil, gravel, sand and clay that nature has revealed to use in the half washed away hillside in Marion County.