Field geology on Hawk Pride Mountain
After rising early and having a camping breakfast of bacon, eggs, and mixed fruit, I set off for the type-locality of the Pride Mountain Formation, which I passed as I arrived at the park. This location is shown in the prologue to this trip. It was easy to locate and I collected some hand samples and took some photos. Here is the official description, which is a compendium of multiple field efforts…needless to say, I didn’t see all of this!
What I did see was dark soil that had eroded from the shale layers within the Mpm (Mississippian Pride Mountain Formation) and sandy layers with both massive and fine layering with cross-bedding. Here are some good images of these features.
This is a typical shot of the thick beds, but they were not continuous even over 100 feet along the road cut. The next photo shows the cross bedding in thinly bedded sandstones.
The bedding surfaces (assumed to originally be horizontal) dipped < 5 degrees in a northerly direction. There was no reaction to HCl (weak acid) at this location, so any limestone was either buried by shale (soil) or not present. I collected a hand sample and brought it home for more detailed examination (sounds good, right). The outside was olive colored but the interior is a brown as in the formal description (above photo), and I saw flecks that are probably mica of some kind (i.e. micaceous). Mica is a flaky mineral that reflects light easily.
My next post will move back to the park and the field relations of this formation (Mpm) and the overlying (i.e. younger) Hartsell (Mh)…
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