Relics

Not far from my mother's house in Fort Worth, a creek has dug a wide gully down through about ten feet of chalky sediment. Walking by, last week, we happened to notice that some of the rocks had shapes, and over a few visits, gathered a number of these fossils. I'm not at all sure of my identifications, and would welcome corrections, but the ones above seem to be ammonites, ancient versions of the nautilus, squidlike creatures that lived in curvy shells. Those below are various snails, aka gastropods. Below left are a kind of echinoderm, sort of fat versions of sand dollars, perhaps the ones known locally as "Texas stars" or "Texas hearts." The twisty, filamentous ones below right are mysterious to me—worms? seaweed?

Comments

[hermit greg]

Back when I spent much of my time with geologists, i was better at fossil identifications than I am now. I do not know what those last ones are, either, but this post reminds me of a trip I took to east Texas while in college. Although most of our time was spent in cars driving from one field to the next, we were fossil hunting with a jeweler who regularly did this in search of gem-quality stones. I came away from the trip with a nice piece of wood-turned-to-agate. But I most remember the fire ants, which had not yet made it north of the Arkansas River. Their aggression fascinated me, such that I wrote a poem about them.

[chad]

Not sure about that last photo either. Could be very small bryozoans, or some kind of shell hash like a coquina. Do you know the age of the strata? Late Paleozoic?

[Caleb Crain]

I don't know the age of the strata, unfortunately. All of these fossils were found in the same place, so perhaps a date could be inferred from the grouping? I don't think it's coquina, because the worms or filaments are all headed in the same direction, as if they grew together.

Fire ants: yes, I remember them from childhood. I remember them well enough that when looking for these fossils, I didn't turn over any rocks incautiously.