Carolina Slate Belt Fossil?

[ncjack99]

A friend at work gave me this rock after they found out about my fossil collecting hobby. They said they found it in 1990 near Crowders Mountain. Crowders Mountain is located in Gaston County, NC about 25-30 miles west of Charlotte which is in the middle of the Carolina Slate Belt. I've never heard of fossils being found in this region however the area is better known for its gold mines. The pictures don't come close to showing the detail on the two "shell" imprints however there is probably enough for some kind of id. Both are circular with the larger one being just under 1/4 inch in diameter. There is a raised spot in the center similar to what you would see in some craters on the moon that have a mountain in the center. Both have rays or ridges radiating out from the center. Any ideas of what these could be even a non fossil explanation would be apperciated.

[Fossildude19]

They look like crinoid stem segment imprints.

Pretty neat.

Thanks for posting them.

[ncjack99]

Thanks Tim. Any guess at the age?

[Rosco]

Coral polyps?

[Indy]

Edited to help these old eyes

I see crinoid stem segments

I'm sure someone familiar with the Geology

of the area will reply with the time perioid

Edited December 21, 2011 by Indy

[Fossildude19]

Thanks Tim. Any guess at the age?

NCJack,

A very cursory investigation from HERE and HERE indicates that area may be more in the "Charlotte belt", even possibly the "Kings Mountain belt".

If I'm reading correctly, there is supposedly some Silurian to Devonian aged outcrops in the Charlotte belt.

Some more thourough research may be needed to pin down an age.

Regards,

[Plax]

slate belt has some poorly preserved Cambrian fossils just across the line in SC. Asbill Pond formation comes to mind but my mind isn't always reliable. Trilobites on worn resistant cobbles were found in plowed fields there around 20 years ago. If there's a Charlotte New York I'd say it was a paleozoic glacial cobble

[Plax]

NCJack,

A very cursory investigation from HERE and HERE indicates that area may be more in the "Charlotte belt", even possibly the "Kings Mountain belt".

If I'm reading correctly, there is supposedly some Silurian to Devonian aged outcrops in the Charlotte belt.

Some more thourough research may be needed to pin down an age.

Regards,

These are igneous or metamorphic belts as far as I know.

[ncjack99]

Thanks for the feedback everyone. It's pretty neat that these fossils came from my area. There's a lithium mine very close to my home and only about 15 miles from Crowders Mountain. Makes me wonder what could be found by checking the reject piles if they were accessible....

Edited December 21, 2011 by ncjack99

[piranha]

Here is another informative LINK and paper:

[ncjack99]

Great articles Piranha. Orginally I mis-stated the rock was from the Carolina Slate belt, but the slate belt is actually somewhat to the east. Crowders Mountain is located in the Kings Mountain belt. Here's the link and supporting quote

http://gis.enr.state...ology_frame.htm

"Between Gastonia and the South Carolina-North Carolina State line, I-85 passes through the Kings Mountain belt. Hard resistant quartzites form Kings Mountain and Crowders Mountain, the tallest peaks to the south."

The age is between 400-500 million years old. Also the Charlotte belt and the Inner Piedmont belt are very close so I wouldn't be surpised if material from all three are mixed together in this area.

[Rockwood]

Coral polyps?

I think what most distinguishes it as a Crinoid is the strait line profile you would see in a side view. Corals are more rounded on the edges and concave in the center.

[FossilDAWG]

I believe Plax is right on with his information. Some poorly preserved but identifiably lower Cambrian trilobites were found near Batesburg SC in the 1980s, when slate blocks were exposed during road construction, but my understanding is that people who have looked for specimens more recently have come up empty-handed. Mines in the Blacksburg/Gastonia/Kings Mountain area are developed in igneous and metamorphic rock. No fossiliferous rocks of an age that might yield either crinoids or corals have been discovered in the Carolina Slate Belt, but adjacent areas in the Blue Ridge Mountains have yielded a very few metamorphosed and tectonically distorted fossils that suggest younger rocks might be present.

Your specimen looks to be in a river or glacial cobble, so it might have been transported some distance from its origin. I haven't heard of fossils in erratics from your area, but in some Alabama streams it isn't unusual to find pebbles with Paleozoic fossils at sites that are 50-60 miles from the nearest present-day Paleozoic outcrops.

Don

Edited December 23, 2011 by FossilDAWG

[ncjack99]

Thanks Don. Very good points. I had wondered if the rock could have been transported from elswhere, but I'm not that familar with the geologic history of the area as it pertains to the last ice age. During my many trips around the park at Crowders Mountain, all I ever found were the quartzites rocks. The ground is littered with rice looking crystals and the rocks are throughly embedded with them too. I believe the main crystals are kyanite and at one time there were plans to mine the mineral, but that didn't come to fruition. Also as an interesting side note according to a friend, the area was used as a artillery testing ground during WWI and occasionally spent bullet cases can still be found. Since this is a state park you're not supposed to remove anything.

Edited December 23, 2011 by ncjack99