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Are these tracks from the Devonian sea floor?


matgerke

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Found this slab near Ithaca, New York in the Devonian Hamilton formation. The underside shows a lot of medium sized lines and gouges, which i interpret to be tracks. Am I wrong? Surrounding rocks were not very fossil-rich.

Thanks for any help identifying these!

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Got pictures?

Tony

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Rusophycus,Craig?or Cruziana?Does Cruziana range through to the Devonian?

Questions,questions

Might it not be an as yet unnamed ichnite,like nopixichnus?

Edited by doushantuo
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That scale is in metres?

I'm not too sure, no markings...but sure is big! From what I've found from a Devonian sea bed is much smaller (found a few that were around a couple feet, but didn't want to drag them up the cliff).

post-22229-0-98699000-1471394935_thumb.jpg

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post-22229-0-84116900-1471394946_thumb.jpg

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He appears to had a gamy leg. Also looks like he might be using a cane.

Amazing what you can tell from traces!

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They do look like trace fossils to Me.

Tony

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I see those all the time, but I have no idea what causes them. When I look closely at the ones I find on sandstone slabs, they look like blobs of mud. Also, I am not sure whether these are positive or negative molds. One observation: notice how they are, on average, oriented in the same direction as if affected by a water current or flow.

Edited by CraigHyatt
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I see those all the time, but I have no idea what causes them. When I look closely at the ones I find on sandstone slabs, they look like blobs of mud. Also, I am not sure whether these are positive or negative molds. One observation: notice how they are, on average, oriented in the same direction as if affected by a water current or flow.

They're usually tube worms or worms of some sort from the Devonian or later...at least from what I know, which is limited :P

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These appear to be consistent with the typical features of: Planolites.

For comparison, here is an example from the Devonian of New York.

post-4301-0-77444000-1471396607_thumb.jpg

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I agree the surface was modified by currents. There appear to be many tool marks, including one impression that vaguely resembles Mucrospirifer. After the surface was covered by sediment (the material of the slab), some organism burrowed through, producing the feature that goes 'against the grain'.

More on tool marks:

https://en.wikipedia.org/wiki/Sole_markings

Edited by Missourian
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A lot of lithologies are the result of turbiditic sedimentation.

examples showing the relationship with trace fossils:

https://www.researchgate.net/profile/Paolo_Monaco/publication/257417872_Ichnocoenoses_in_the_Macigno_turbidite_basin_system_Lower_Miocene_Trasimeno_(Umbrian_Apennines_Italy)/links/54070f530cf23d9765a833ff.pdf

https://www.researchgate.net/profile/Duncan_Mcilroy/publication/239920277_Ichnological_characterization_of_EoceneOligocene_turbidites_from_the_Gres_d'Annot_Basin_French_Alps_SE_France/links/542949c10cf2e4ce940c98ae.pdf

Sometimes Paleozoic sediment aren't what they at first appear to be: a lot of Paleozoic bioherms are really "resedimented carbonate breccias".

agreed:those are convex hyporelief Planolites..

Most straight (sub)horizontal burrows end up in that ichnogenus

PLANOLITES:

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0070920

Edited by doushantuo
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Does anyone else see the crinoid in the lower third? Wishful thinking?

I would say the parallel groves are current-formed and the ones going crossways are an ichno-fossil like Planolites.

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This chain is hilarious!

Wish there was a crinoid here, but in person it doesn't really look like it.

Thanks for all your help!

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