Jump to content

Memorial Day in the Salem Limestone


Recommended Posts

FossilNerd

I spent Memorial Day morning fossil hunting the Carboniferous in the Salem Limestone (Formation) of Central Kentucky. Hunting the Salem at this particular road cut is a bit of a gamble. There are things to be found here, but good weather, timing, and a bit of luck are needed to have a chance at coming across anything worth writing home about. I have found almost complete Conulariids here, but also watched them crumble in my hands. I didn't bring home bucket loads of fossils this time out, but still, it was a good day. The sun on my face, flowers to smell, and plenty of rocks to break. :) 

 

The bottom half of the Salem Limestone isn't limestone at all, but friable shale that is grey in color. It can be interbedded with layers of a limestone, or a densely packed detritus layer.

IMG_0716.thumb.JPG.711f860b8f3e0d16dea69ee30bbfd925.JPG

 

The Shale is full of fossils, but alas it weathers poorly. If it is exposed for more than a week it crumbles in your hands and turns into the rubble that litters the bottom of the cut. Forget about trying to split any of it when wet as it also tends to break apart. The key to hunting the stuff is to wait for a hard rain that breaks fresh slabs off the face of the exposure, hope for a couple of days of sunny weather to dry it out, then split it shortly after. Wait much longer and the whole boulder will start to fall apart. This is made worse during the colder months with freeze thaw cycles.

 

 

The detritus layer is just that. A dense layer composed mainly of fossil bits and pieces. It's still worth a look as I found some crinoid cups and trilobite fragments here.

 

The upper part of the formation is limestone. Two different varieties, one coarse and one fine grained. Both are more sparse with fossils than the shale layer, with the coarse grain being the more fossiliferous of the two. You can find  brachiopods, coral, and occasionally trilobites here.

 

Here is a picture of the tallest part of the exposure. With 3 distinct level cut into the hills side. I channeled my inner mountain goat and climbed, scrambled, and hiked my way up, down, and around every level. Each level is 12-15 feet (4-5 meters) high.

 

IMG_0723.thumb.JPG.d8f7acd98faea4d970806d17103fa060.JPG

 

 

Some pictures from the field:

IMG_0714.JPG.3a4b4cac81caefcdf228370177f79305.JPG

IMG_0728.thumb.JPG.3aed4d13fdb624efeb6b03f1870f1604.JPG

IMG_0740.thumb.JPG.4eda48153d1eb31a934238e8900c1631.JPG

 

 

And here are a few of the things I brought home with me.

 

Chondrites?

IMG_0767.JPG.059386c9eae57bb1865b0c254c4f9797.JPG

 

I'm unsure of this one, it may be nothing. Possible ichnofossil? Feeding trail perhaps? Smaller ones (Helminthopsis) can be found here.

IMG_0765.thumb.JPG.7af1b49354a492a61c836cf283e4a3de.JPG

IMG_0763.JPG.bc227a1c9975ac4d1d5ef90e9814d336.JPG

 

I picked this up because of the large brachiopod and the tiny gastropod.

IMG_0770.JPG.37950fb58b574f9605a33f6f97b43bd5.JPG

 

A sampling of coral. Syringopora maybe?

IMG_0771.thumb.JPG.483349218c70561200d45910a445bb55.JPG

 

A very weathered trilobite pygidium. It is only about 1cm long.

IMG_0774.JPG.19a4fbadc81435217d3382405839b43a.JPG

 

Here is a heartbreaker from a previous trip. I learned the hard way that the friable shale here is better split when dry. A conulariid that split nicely, but the wet rock caused it to fall apart. You can see bits and pieces left as well as the lingering impression. It would have been a nice one had it held together. 

 

IMG_E0772.thumb.JPG.2119db926bfbc55057d29f8be53e0771.JPG

 

 

 

I picked up a few other things as well, but failed to take pictures. Some of the small horn coral and bryozoan similar to what was shown in the field pictures.

 

I may not have come home with my backpack overflowing, but I still had a good time splitting shale and climbing up and down the road cut. Just getting out and about was enough for me.

 

Oh... I mentioned smelling flowers. I'll leave you with a sampling of the local flora that added to my scenery.

 

IMG_0726.thumb.JPG.4eb4ccf29a1c21f8cb5a9940b61ae305.JPG

IMG_0727.thumb.JPG.31c15be266d8e53a1c5918bd45ece4e5.JPG

IMG_0724.thumb.JPG.c00c57556fd29e89b11cc15fd95626dd.JPG

IMG_0736.thumb.JPG.a6e5777fa8b38ec75f0af8437ac7a8f5.JPG

IMG_0738.thumb.JPG.385714d96e457d67f55c2992ab155320.JPG

IMG_0745.thumb.JPG.11f58908c7e95c3cccf1ec846f66522c.JPG

  

  • I found this Informative 1
  • Enjoyed 12
Link to post
Share on other sites
Fossildude19

Great report and finds, Wayne!

Thanks for posting it - glad you could get out. 

  • Thank You 1
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...