Fossil Hunting in Post Oak Creek

We went on an adventure to try a fossil hunting site that I just learned about called Post Oak Creek in Grayson County, Texas.  At one time this area was all under water and this is an easy site to access and hunt for fossilized shark teeth and other fossils of marine life that date back to the Great Flood (or the Cretaceous period which is believed to be 60-145 millions years ago). 


I am proud that my kids are up for exploring new places with me, even if they dress fancier than any explorer would ever consider dressing.  I love this little girl so much!


The site is about an hour from our house but we also had to stop at Tractor Supply to pick up rain boots since we were going to be walking through a creek.

The area that most people go to access the creek is at the Travis Street bridge in Sherman.  The path to the creek was well-worn.  There were several families and groups already in the creek on this day.


The creek was shallow and lined with trees.  It was easy to wade through but we were glad to have our rain boots.  


This is what we saw as we looked into the water.  Lots of little pieces of rocks and probably some fossils mixed in.


Nicholas quickly found a tooth!


The kids wandered down the creek but Stuart had a lot of success just staying in one area where wading in the creek wasn't necessary.


It is very helpful to bring some sieves or even kitchen strainers to help sift through the small gravel.  I got a set of 5 different size sifters from Amazon and the kids had fun sifting for fossils.


It is also good to bring some hand trowels and something to carry your finds in like a bucket or backpack.


More teeth!




Rachel was wearing rain boots but some of the spots in the creek were deeper than her boots were tall.  She didn't mind.  I always expect my kids to get wet if there is a creek around.


If you get tired of wading in the water to search the bottom of the creek, you can also search along the bank.  It all looks the same and there are lots of fossils throughout both of them.


We wandered down the creek some to explore.  The water got deeper as we walked and at times the bank disappeared so we were limited in how far we could walk.  It was a nice little hike and we searched for fossils all along the way.


When we get home from fossil hunting, we always clean our finds and spread them out on a towel to dry.  Here is an overview of our collective bounty.  I was able to ask some members of the Dallas Paleontological Society for help in identifying some of these.  I'll post their comments below in quotes.


We found more teeth than we have ever found on a fossil hunting trip!


Stuart had the coolest find of the trip.  It looks like a vertebrae of some kind.  "It doesn't look like the typical vertebral body that is usually found.  I am thinking it could be an intact neural arch from a fish vertebrae without the vertebral body.  If so that would be a fairly rare find.  Nothing of great value or anything, but rare because these parts are fairly fragile and rarely survive.  When they do, they are usually still attached to the vertebral body."


I don't know what these two things are.  I still need to research them.


We thought this might be some type of a vertebrae but someone from the Dallas Paleontological Society thinks it is an oyster fragment.


The piece below is "from the Kamp Ranch limestone.  It is the 2nd layer from the top of the Eagle Ford group.  It underlies the Arcadia Park formation.  It looks like a possible ichnofossil aka trace fossil from a burrowing creature.  My personal belief from personal observations in the field is that it is the trace burrow of a bivalve."  Note: I think of a trace fossil as a fossilized evidence of a creature's movement through or across a substance.  It is different than a fossilized impression of the creature's actual body.  A burrow is the remainder of a tunnel that a creature created in the ground or sea floor.  Burrows are trace fossils.


I really thought this piece below looked like a piece of bone.  But two DPS members agreed that is is a burrow cast in limestone.  Not as exciting as a bone but still amazing to me to find something like this.


This piece of bone has a clean cut so it is probably from a modern cow from a slaughterhouse that is up the creek.


The following is "a fragment of an Eagle Ford septarian nodule.  Looks to be largely calcite in yellow to cream.  The brown, root beer colored crystals may be aragonite."


The following is a cluster of Bellaplicata oysters.


This piece below is a mystery.  It could be man-made but it is too light to be concrete.  Someone from the Dallas Paleontological Society said, "I don't think it is concrete.  It see a fragment of a Pectin bivalve.  Probably an off layer of Kamp Ranch Limestone."  The line through the middle could be a burrow from some kind of small critter.   I don't know what it is but it is interesting looking.

The easiest access to Post Oak Creek and the way we entered was in Sherman on Travis Street where it crosses the creek.  Park on the road near Bob's Muffler Shop and Danny's Paint and Body Shop.  This is a well-known spot for fossil hunting and cars park here everyday.  The people in the town don't seem to mind at all.  You will see a path going down to the creek.  There is one steep area to get down to the creek but it wasn't too difficult.  I would love to see pictures of your fossil finds if you go!

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