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It's been three weeks since I made the move from Texas to Missouri. During that time, I've been extremely busy trying to get the old homestead back in shape (new roof, bebuilding the barn, new doors on the house, cleaning out the basement and garage of almost 30 years of my parents being pack rats, etc.). I'm still in the process of unpacking and unfortunately much of my paleo literature is stored in the basement until I can set up my "man cave", so I'm not sure exactly what formation these are.

Today I decided to take a break from working and check out a couple of outcrops I had noticed in the area. With outcrops of this size, they're not hard to notice. I wasn't able to find any indication of fossils, but it felt good to be out and exploring again.

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Glad you're making good headway, and making a little time for yourself too. :)

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Great way to clear your head anyways. Looks gorgeous! (scuse the pun)

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Glad to see your post and that you are starting to get settled in.. :)

That formation looks grainy like sandstone.. You will get to the

fossil formations soon after some trial and error..

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Looks like a great place for possible Indian artifacts------Tom

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Glad to see your post and that you are starting to get settled in.. :)

That formation looks grainy like sandstone.. You will get to the

fossil formations soon after some trial and error..

It's full of chert. The creek bed is pretty much nothing but chert.

I've located some other nice looking outcrops that I'm going to be checking out in the near future (hopefully).

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Looks like a great place for possible Indian artifacts------Tom

We are just outside of the Trail of Tears State Park. This is where the Cherokee Indians were forced to cross the Mississippi River during their forced relocation from the southeastern US to Oklahoma.

I found many arrowheads when I was a kid growing up in this area, but I'm at a loss as to where they've gone now. I was hoping to find them while we've been cleaning the house and barn out, but no luck so far.

You can bet I'll be keeping an eye out for more during my fossil hunts.

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Steven,

Glad to see you are settling in, and starting to explore your "new" area. :)

Best of luck to you in your reconnaissance!.

Regards,

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With all the chert and the geology just across in Illinois being lower Devonian Clear Creek Chert mostly (may be some underlying Grassy Knob also??) I imagine this is same material in your area, in and around the Trail of Tears Park in Illinois there are good fossils in parts of this unit:

From a couple of the ISGS field trip books: At Trail of Tears State Pakr (Illinois) Fossils include brachiopods (Amphigenia curta, Eodevonaria melonicus, Strophomena, and Spirifei), the trilobite Dalmanities pratteni, rare crinoid fragments, rare graptolites, and lots of crinoid stems.

Some locations such as site below in Illinois are altered to Novaculite (hyrdothermal silica) more or less but the Upper part of the Clear Creek is very fossiliferous also (you may be too low where your pictures taken I assume the Clear Creek and not underlying also Grassy Knob (not as many fossils in that)

Stratigraphic Description of

Devonian Rocks

A general stratigraphic description for the Devonian rocks in the area (Devera 1994) is reproduced below. The pit itself is largely in the Clear Creek Chert, al- though the boundary between the Clear Creek and the underlying Grassy Knob is not clear. Clear Creek is very fossiliferous, and the Grassy Knob is not, and that characteristic makes for the best distinction.

Lower Devonian Dutch Creek Sandstone (10–30 feet thick) Sandstone, white (weathering dark gray), fine- to medium-grained, well-sorted quartz arenite composed of rounded, frosted grains; locally abun-
dant molds of corals, brachiopods, and other fossils. Much of this sandstone is an intraformational breccia cemented with silica and dark brown iron oxides. The lower contact is sharp and at least locally disconform-
able. Although it has been classified as Middle Devo- nian, the fossil content of the Dutch Creek more closely resembles that of the Clear Creek below it, and thus this unit may be Lower Devonian in age (Devera, personal communication 2003).

Clear Creek Chert (200–300 feet thick) Chert, microcrystalline silica or tripoli, and minor limestone. Chert (largely silicified limestone) is a dull to semivitre- ous white with orange- and red-stained zones. Bedding is thin and wavy to tabular; red clay partings are com- mon. The chert is mainly porous to microporous, but some is dense. Brecciated chert occurs locally near the tops of ridges. Ledge-forming chert occurs sporadically in the unit; its occurrence appears to be partially fault- controlled. Chert is gently folded and highly fractured in most places. Microcrystalline silica (such as at this mine) is white to very light gray, orange- and red- stained, and relatively soft and friable; it has indistinct thin layering and some clay partings. Limestone in the Clear Creek when present (likely not here as it was re- moved in this district by the hydrothermal alteration) is grayish brown, thin-bedded lime mudstone. Fossils are abundant in the upper part of the unit, including trilo- bites Dalmanites pratteni, Odontochile sp., Leonaspis sp., Phacops cristata, and Cordania sp., and the brachi- opods Eodevonaria arcuata, Strophostylus cancellatus, and Amphigenia curta along with abundant spiriferid and strophenmenid brachiopods and pelmatozoans. Ich- nofossils include burrows (typically vertical), borings in brachiopod shells, and large domichnia cavities. Gray chert containing abundant spiriferid brachiopods and crinoid columnals at the base of the unit may represent the Backbone Limestone. The lower contact is poorly exposed but appears conformable.

Grassy Knob Chert (200–250 feet thick) Chert and microcrystalline silica (tripoli). Chert is white to very light gray with gray, yellow, and orange stains. Typi- cally, this chert is dense, novaculitic, and medium- to thick-bedded. Fossils are rare and represent the best way to distinguish it from the overlying Clear Creek Chert. Brecciated chert occurs throughout the unit but is most common at the top. Below the upper breccia zone is an interval of very porous, popcorn-textured chert riddled with what appears to be horizontal burrows. The Grassy Knob contains less clay and more styolitic part- ings than the Clear Creek. The lower contact is grada- tional. Microcrystalline silica (tripoli) is similar to that in the overlying Clear Creek, but generally occurs in thinner layers and contains a greater proportion of chert.

Bailey Limestone (300–325 feet thick) Limestone, chert, minor shale, and microcrystalline silica (tripoli). Limestone is light brown to light yellowish gray, dolo- mitic, argillaceous lime mudstone; its thin wavy beds contain abundant gray chert nodules. The upper part of the unit, stained yellow to orange in some areas, includes chert with a “brain” texture interbedded with microcrystalline silica and dense, nodular chert. Sponge spicules increase in abundance upward. Fossils are common in the upper 100 feet; they include the trilo- bites Huntonia palacea, Phacops sp., and Dalmanites sp. along with crinoids and the trace fossil Zoophycos. The lower part of the unit is relatively unfossiliferous. Near the base is greenish gray cherty limestone and bedded chert with interbeds of green shale. The lower contact is gradational.

STOP 7. Birk-McCrite Quarry UNIMIN Specialty Minerals, Inc., Lower Devonian Clear Creek Chert. Located northwest of Tamms (SE1⁄4SE1⁄4, Sec. 21 and NE1⁄4NE1⁄4NE1⁄4, Sec. 28, T14S, R2W, 3rd P.M., Mill Creek 7.5-minute Quadrangle, Alexander County). On the day of the field trip, we will park along the road. Follow the directions of ISGS staff.

Another site STOP 8. Tatumville Novaculite Quarry Lower Devonian Grassy Knob Chert. Located north of Tamms at Tatumville (E1⁄2NW1⁄4, Sec. 36, T14S, R2W, 3rd P.M., Mill Creek 7.5-minute Quadrangle, Alexander County)

The quarry at Tatumville is made up of two Lower Devonian formations: the lower part is the Grassy Knob Chert and the upper part is the Clear Creek Chert. The Grassy Knob Chert is white to very light gray, yellow with orange and red iron oxide stains. Typically, the Grassy Knob Chert is a dense novaculitic chert that is medium- to thick-bedded. Fossils are rare in the Grassy Knob. Brecciated chert occurs throughout the unit but is most common near the top. Below the upper breccia zone is an interval of very porous, popcorn-textured chert riddled with what appears to be horizontal bur- rows. The Grassy Knob contains less clay and more stylolitic partings than does the overlying Clear Creek Chert. This unit also contains microcrystalline chert, which is quartz crystals that range from 5 to 10 μm in length. The base of the Grassy Knob is not present in the quarry but is gradational with the Lower Devonian Bailey Formation, which is also silicified in this area.

The Clear Creek Chert contains bedded chert, micro- crystalline silica, and minor amounts of limestone and clay. It is white with orange and red-stained zones.

The bedding is thin, wavy to tabular. The texture of the chert ranges from porous to microporous to dense and novaculitic, but the chert is thinner-bedded than the overlying Grassy Knob. Fossils that occur in the Clear Creek include Odontochile, Leonaspice, Phacops, and Cordania trilobites, which are all rare; also included are the brachiopods Eodevonaria, Strophostylus, and Amphigenia. Spiriferids are more common

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I was trying to figure out why your site looked familiar and that wavy bedded nodular character is what this is like. I would scour this because you can find some layers in the upper part the formation that are very fossilifereous and with the siliceous nature while molds they are very cool fossils -- brachiopods, corals and trilobites for example... as the material I posted. If I were you I would for sure look these outcrops over closely.

Russ

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Here are links to the ISGs with those two guidebooks if you want to get them all and see some of the geology just south and east of you also:

http://library.isgs.uiuc.edu/Pubs/pdfs/ftgb/ftgb2008A-horseshoelake.pdf

http://ia600803.us.archive.org/30/items/guidetogeologyof1998deve/guidetogeologyof1998deve.pdf

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The state of Missouri does not have quite the same online data but what they had showed me that in area around the park and where you are there is Everything from the Dutch Creek Ss down through the Baley Limestone sitting on Silurian in the area. I would be exploring every hollow -- Devonian sites and Silurian! Some good fossil potential there!

russ

Edited by trilobiteruss
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Russ,

Thanks for the valuable information. This move to MO has been in the works for a while so I've been collecting some info about the area and been reading up on it as much as I can. This additional info is very helpful.

I was trying to figure out why your site looked familiar and that wavy bedded nodular character is what this is like. I would scour this because you can find some layers in the upper part the formation that are very fossilifereous and with the siliceous nature while molds they are very cool fossils -- brachiopods, corals and trilobites for example... as the material I posted. If I were you I would for sure look these outcrops over closely.

Russ

I had noticed the wavy pattern as well. Obviously from the height of these outcrops, I have no way to inspect the upper part of the outcrops (without rappelling, I guess), but I saw no indication of fossils in the creeks at the base of the outcrops.

These two outcrops are actually the opposite sides of the same hill. This is where two creeks merge together and each creek has cut these outcrops from each side of the hill. I may just have to go back and check it out more closely.

I've also read that trilos have been recovered from the Bainbridge formation, just south of the Trail of Tears State Park in MO. I'm not far from Bainbridge Creek, so I hope to check this area out very soon.

Thanks again!

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Sward:

Glad to add to your knowledge, wish I had some of this in my "backyard" kinda boring glacial stuff in central Illinois. If you go up some of the hollers on the hills you might find outcrops higher up and some of of the Clear Creek and other two have some good trilobites (what I keyed in on ha ha) Yes the Bainbridge has some good trilobite material also. You have a great location!

russ

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