Local Railcut

[aek]

Went out to a railcut that slices through upper Racine formation. This locality is only 10 minutes from my house. I almost never visit it because of scarcity of fossils, however I was reading a paper that mentioned forams in chert and decided to take another look. 

Here you can see the beds dipping gently to the east. This is interreef strata. Closeby is/was a huge reef, now filled with garbage.

 

Here is a chert nodule to be sliced up. Also, found a silicified coral and packed in my bag.

 

Disturbed this guys slumber.

 

Silicified Favosites coral slice.  Interesting to see sediment infilling. 

 

Microscope pics showing tabulae. These are just quick slices using a tile saw and submerged in water to bring out detail.

 

 

 

Chert slices magnified. It appears to be echinoderm debris and possibly some coral spicules? (Correct me if I'm wrong about the spicules...)

 

Columnal with spines.

 

 

And finally, I believe this is a foram, the only one I could find. Difficult to photograph. Thanks for reading.

Edited July 19, 2021 by aek

[deutscheben]

Very interesting, a different way to look at fossils. The geometric pattern in the coral is quite eye-catching.

[aek]

Not sure entirely, but I think this star-shaped fossil is a foram. Measures 1mm. I don't know what else it could be. These are probably all forams, not echinoderm debris. Ha! What do I know?

 

 

 

 

Edited July 25, 2021 by aek

[aek]

After doing more research, I believe the star is a heteractinid sponge spicule, Sexiradiates Fig. 9

Watkins 1997 .Silurian Sponge Spicules of the Racine Formation Wisconsin, Journal of Paleontology Vol. 71, No. 2

 

 

 

[aek]

I dissolved some nodule fragments in 10%HCl for a couple hours and then sieved with 150 mesh and rinsed with H2O. This yielded a few nice examples.