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This is my first "new topic" post to the FF, so I hope I'm doing this correctly. If you have a microscope or equivalent and a current or potential interest in micro-fossils, you might enjoy collecting at the following historic locality: Mississippian Salem Limestone, about 5 miles east of Salem, Indiana off Rt. 160; Spergen (Spurgeon) Hill, railroad cut (Manon RR) paralleling S. Harristown Rd, 0.75 mi north of Rt. 160; south end of Trackside Road; approximately 140 meters S of Harristown, Washington Co., Indiana; diminuitive fauna; Universal Transverse Mercator (UTM) coordinates: 16S 585024.04 4272332.25. My first introduction to micro-fossils was in a paleontology lab I took during the 70’s with the focus of study on the foraminiferid, Endothyra baileyi (now called Globoendothyra baileyi). These tiny specimens were labeled “Spergen Hill” on their container without further description. A few years later, I was able to locate the source of the specimens as the type locality for the Salem Limestone (formerly, Spergen or Spergen Hill Limestone) of Middle Mississippian or Meramecean (Valmeyerian) age. Sratigraphically, it sits above the Harrodsburg Limestone and beneath the St. Louis Limestone. The locality is a railroad cut at Spergen Hill, just south of Harristown, Washington County, Indiana. The cut is relatively narrow and much caution is advised upon the advent of trains entering the cut. The rock at this locality is a medium to coarse grained, tan to gray, crossbedded calcarenite containing mostly microfossils. Macrofossils (somewhat sparse) are present in the formation but nowhere near the quantity of the microfossils (G. baileyi has been estimated at 1,000 / in3 in some portions of the strata). Besides single-celled eukaryotes (e.g., Globoendothyra), representatives of most of the major phyla are present in diminuitive form or as tiny fragments of the macro fauna (spines, plates, columnals, etc.) I’ve visited the location at least three times in the past and besides collecting macrofossils on these visits, I have also accumulated a quantity of the rock containing the microfossils. On arriving home, I pulverize the collected rock with a sledge to a fine granular size and wash and strain the residue through a porous cloth to remove any extra fine material (rock dust) The washed residue is then dried and placed in labeled plastic bags. Then, in the dead of winter when collecting is not possible for me and the “urge” to collect is compelling, I drag out a bag, place some of the residue in a shallow container under my scope and go fossil collecting and identifying! I use a very fine-pointed forceps, which I periodically ground to a piece of rubber (to avoid static electricity buildup) to pick out fossils from the residue. I find it a bit better for collecting the micros from this locality than using a wetted fine paintbrush. This location has been estimated to contain over 100 species of invertebrates on a micro level. More information can be found at http://www.fallsoftheohio.org/SalemMicrofossils.html. The attached photos were taken for a program I was giving on Indiana fossils to illustrate single-celled eukaryotes (Protozoa). The first photo shows a random selection of micro-specimens of various phyla collected from the residue with an emphasis on the G. baileyi. The second and third show sorted G. baileyi specimens and G. baileyi specimens with matrix, respectively. Two free texts with plates are available on some of the Spergen Hill microfauna at the following websites: Whitfield, R.P. On the fauna of the Lower Carboniferous limestones of Spergen Hill, Ind., with a revision of the descriptions of its fossils hitherto published, and illustrations of the species from the original type series. Bulletin of the AMNH; v. 1, article 5. (free download) https://books.google.com/books?id=ebYPAAAAIAAJ&pg=PA241&lpg=PA241&dq=whitfield,+R.P.+On+the+fauna+of+the+limestones+of+Spergen+Hill&source=bl&ots=iFhHvpc7qf&sig=XNpUBo45hKPRICv5fLdb0AlJktA&hl=en&sa=X&ei=pO8_Ve70G-vlsATq-4EQ&ved=0CCQQ6AEwAg Cumings, E.R. et al. Fauna of the Salem Limestone of Indiana. (free download). https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0CB4QFjAA&url=https%3A%2F%2Fscholarworks.iu.edu%2Fdspace%2Fhandle%2F2022%2F12889&ei=G_o_Va3_CveasQSCu4HADA&usg=AFQjCNGsTNbr2RKBBebd6bnuISOcqvMsPw

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. 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. Some pictures from the field: And here are a few of the things I brought home with me. Chondrites? I'm unsure of this one, it may be nothing. Possible ichnofossil? Feeding trail perhaps? Smaller ones (Helminthopsis) can be found here. I picked this up because of the large brachiopod and the tiny gastropod. A sampling of coral. Syringopora maybe? A very weathered trilobite pygidium. It is only about 1cm long. 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. 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.

I stopped by a new road cut today to see if it would be a viable hunting spot. One of the things I found there was this interesting piece. Maybe an Ichnofossil? Some type of burrow or feeding trails? According to the USGS map, the cut is Salem Limestone which is Upper Mississippian in age. Any ideas? This small piece that I picked up came from a larger slab that was over a meter wide. The whole rock was covered in these and they are in between the layers. The big ones are only about 1cm across and most are half that. A photo from the field... This is a picture of it wet...

I stopped by a prospective road cut today. Upper Mississippian (Salem Limestone). I didn't stay long so there is no trip report. Sorry... I promise a full report the next time I am there. I walked it for a few minutes and picked up a hand full of things. I mainly wanted to see if anything could be found and if it warranted spending more time there. I did split a couple of rocks to take a peek. To my amazement, on one of the splits, I found my first recognizable trilobite piece from out in the field! I have found a handful of trilo-bits in gravel drives, parking lots and the like, but never one when I was actually out hunting, so I am super excited! It's a little pygidium and I almost missed it. It is about 10mm long by 14mm wide. I don't know the area very well yet, but I have read that Griffithides bufo can be found in the Salem Limestone formation. I know it may be a long shot, but can any ID be made from this pygidium? The split wasn't the greatest, but I was able to save the positive and negative pieces.