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JStone

Upstate/Western NY Rugose coral variety?

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JStone

Good morning! I have been puzzling over this piece of what I believe to be a type of rugose coral, a little over an inch across at its widest, 1.5 inches tall but a fragment of a whole.  The closest thing I could find might be ketophyllum perhaps?  It was found on the western edge of the Otisco Valley in central/western NY state, between Skaneateles and Otisco lakes. The layers if the area I am know of are is Ordovician/Silurian/Devonian, i am not certain as to its original bedding plane location as it was a post thunderstorm erosion find, all sorts of fresh material came down the gorge, but i think it came from above the “famous” layer of Staghorn coral that emerges on the east side of Skaneateles lake.  It popped right out of the shale I split and is almost graphite in appearance, the "stump" nodes that look like broken off appendages and the vertical pattern (vs the typical horizontal growth bands in the common staghorn corals) make it very different from anything I have found in the area, it almost looks soft-bodied, realizing how unlikely that is.  I love the detail in this piece, it looks like there may be preserved damage/healing that occurred in life but I may be reading too much into that thought. 

 

Additional angles attached, just quick ipad shots but they may be helpful.  No visible septa on either end, nothing radial or even patterned, although it looks like there may have been an internal, central structure.  Thank you!

 

It may have come down from the Devonian Otisco  Member of the Ludlowville  Formations  (Upper  Hamilton  Group)?

Moon Hill Graphite Crop.jpg

8AA77E20-7B06-4388-AEFB-01E4CCD0F7EC.jpeg

 

05533665-C66B-41AF-B87B-FFE1BC122BE7.jpeg

99FCF470-E066-4F60-BA5A-346AABF8A1D6.jpeg

Edited by JStone
Additional photos

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ynot

Welcome to TFF!

     it does not look like rugose coral to Me.  but additional pictures of the other sides and ends may change that opinion.

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Fossildude19

Definitely not a rugose coral. Need more pictures, as Ynot says.  

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Fossildude19

I think this is a plant limb or root cast. :unsure: 

Are there Devonian exposures in the area at all? 

As it was found loose as float, it may have been washed there from elsewhere. 

 

 

 

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Kane

+1 for some kind of plant material (likely Devonian or younger - an erratic in relation to the stated dominant lithology). A rugose coral would be showing internal structure, such as septae, which are absent in this piece. 

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Fossildude19

Looks like that area has mostly Devonian, not Ordovician.

Plant debris is fairly common in the Devonian exposures of Central and Eastern NY. 

3 dimensional casts are a bit more rare, as most plant remains are compressed carbonaceous films. 

 

Map from HERE.

 

map-bedrock3.jpg   NYSBG.JPG

 

                                                                                                                                        This map from HERE.

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ynot

With the additional pictures added to the first post, I agree with the plant id.

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JStone

Man I was waaaay out in left field! Thank you for the thoughtful hive-minding!  I have wondered for a long time and was looking in the wrong direction.  I make a trip to that washout every time I am in the area.

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Bronzviking

Welcome to the Forum from sunny Florida! Nice chunk of fossil. The first pic definitely looks like a petrified wood branch with smooth bark. You could research indigenous trees of Western NY with smooth bark to narrow it down.

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Innocentx

Good looking piece of flora. 

Welcome to the Forum from Kansas.

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Auspex
24 minutes ago, Fossildude19 said:

It is more of a cast of the exterior only

This is correct. Structural lignin was just coming into existence in the Devonian, so tree limbs and trunks in ground contact decomposed too quickly to become mineralized (outside of a few very rare examples).

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Bronzviking
5 hours ago, Fossildude19 said:

It's not actually petrified wood, as the inner structure isn't really preserved. 

It is more of a cast of the exterior only, so I don't believe you could classify it as Petrified Wood. 

There are a few Devonian plants known from NY, ... but it is likely that this is from Archaeopteris or Wattieza/Eospermatopteris;) 

Tim, I guess I'm not following your terminology. It's not petrified wood, but it is an external cast of a limb? Aren't they one in the same? I found this on https://therockshed.com/petrifiedwood3.html. A limb cast is a psuedomorph where the original wood has been replaced by chalcedony. These pieces form when a tree was buried by ash. The wood is burned away by the hot ash and a "cast" is left. Minerals in the groundwater then permeated the cast, replacing the original organic matter and turning it to stone. The result is a rock that has the form of a tree limb. Some of these casts show the bark and wood textures. So your saying it's a fossil but not petrified. Could you please explain how this was formed so I can fully understand this process? Thanks!

 

 

 

 

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FranzBernhard
18 hours ago, Bronzviking said:

The wood is burned away by the hot ash and a "cast" is left. Minerals in the groundwater then permeated the cast, replacing the original organic matter and turning it to stone.

The process as described above is somewhat contradictory. If there is a real cast (= mold) (a hollow, empty space, "Gußform" in german), nothing can be replaced (in the strict sense of the word), the empty space can only be filled with something, resulting in an "Ausguß"/"Gußstück".

 

And there can not be a hollow, empty space (cast = mold) and something to be replaced (original organic matter) simultaneously.

 

I think, it very much depends on the definition of "cast". Its easier in german, there are many technical words available with different meaning (Gußform, Gußstück, Ausguß, Abdruck, etc.). In english, I think "cast" is both: "Gußform" (the hollow, empty space to be filled with something) and "Gußstück"/"Ausguß" (the material infilling the "Gußform").

Edit: "Cast in the same mold" - now everything is clear :).

And: thanks, @Innocentx, for clarification! :fistbump:

Franz Bernhard

Edited by FranzBernhard
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Innocentx
10 hours ago, FranzBernhard said:

I think, it very much depends on the definition of "cast".

I've had trouble with these various definitions, mold/cast. I worked in metal and the cast is referred to as the resulting product of pouring hot metal into a mold. In paleontology it seems these terms are reversed. Slightly confusing.

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FranzBernhard

@Innocentx, you are absolutly right!

"Mo(u)ld" is the "Gußform", but my dictionary also refers to "cast" as "Gußform".

And vice-versa: "Casting" and "mo(u)ld" are the "Gußstück" - according to my old dictionary :o.

"Cast in the same mo(u)ld" - also from this dictionary ;). Now everything is clear :fistbump:!

Franz Bernhard

 

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Fossildude19

@Innocentx  @FranzBernhard

 

Uggh! Let's not start this conversation again!  :P 

This has been discussed many, many times here on the Forum.  :rolleyes: 

 

 

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FranzBernhard
21 minutes ago, Fossildude19 said:

Uggh! Let's not start this conversation again!

Thanks, will do it! ;).

So, the item in question is a cast, the infill of a former empty space. The empty space was created by decomposition and "disappearence" of a piece of wood.

It is clearly not petrified wood, but the cast(ing) of a piece of wood.

Franz Bernhard

 

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Fossildude19

Right on the money!  :) :dinothumb:

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Fossildude19

 

20 hours ago, Bronzviking said:

Tim, I guess I'm not following your terminology. It's not petrified wood, but it is an external cast of a limb? Aren't they one in the same? I found this on https://therockshed.com/petrifiedwood3.html. A limb cast is a psuedomorph where the original wood has been replaced by chalcedony. These pieces form when a tree was buried by ash. The wood is burned away by the hot ash and a "cast" is left. Minerals in the groundwater then permeated the cast, replacing the original organic matter and turning it to stone. The result is a rock that has the form of a tree limb. Some of these casts show the bark and wood textures. So your saying it's a fossil but not petrified. Could you please explain how this was formed so I can fully understand this process? Thanks!

This item has no original wood replacement, no chalcedony. The branch fell in the mud. I'm guessing here, but it probably rotted away, but not before leaving a mold of the branch.

(Which, by the way, I think is decorticated - missing the outer layers of bark)

Mud then filled the void/mold/imprint of the branch. It turned to stone, and 370 million years later, ... there is your limb/branch cast. :) 

Not sure if the remaining matrix is limestone, mudstone, or sandstone, but definitely NOT chalcedony, ...  but either way, there is no internal structure preserved. 

There fore it can't really be considered "Petrified wood". 

 

20 hours ago, Bronzviking said:

Also I found this post that might be useful.Devonian petrified wood

http://www.thefossilforum.com/index.php?/gallery/album/799-devonian-petrified-wood/

I would say that technically speaking, Roman used the wrong terminology here, as there doesn't appear to be internal structure preserved.

Probably better to call these limb or branch casts. 

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Bronzviking
5 hours ago, Innocentx said:

I've had trouble with these various definitions, mold/cast. I worked in metal and the cast is referred to as the resulting product of pouring hot metal into a mold. In paleontology it seems these terms are reversed. Slightly confusing.

I agree, confusing. I'm familiar with shell molds and casts but never knew there were plant/wood casts. Learn something new everyday on TFF. :)

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Bronzviking
3 hours ago, Fossildude19 said:

 

This item has no original wood replacement, no chalcedony. The branch fell in the mud. I'm guessing here, but it probably rotted away, but not before leaving a mold of the branch.

(Which, by the way, I think is decorticated - missing the outer layers of bark)

Mud then filled the void/mold/imprint of the branch. It turned to stone, and 370 million years later, ... there is your limb/branch cast. :) 

Not sure if the remaining matrix is limestone, mudstone, or sandstone, but definitely NOT chalcedony, ...  but either way, there is no internal structure preserved. 

There fore it can't really be considered "Petrified wood". 

 

I would say that technically speaking, Roman used the wrong terminology here, as there doesn't appear to be internal structure preserved.

Probably better to call these limb or branch casts. 

Tim, Thanks for taking the time to explain in layman terms. Makes sense to me now. :)

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Innocentx
6 hours ago, Fossildude19 said:

Let's not start this conversation again! 

ok

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