Stocksdale Posted February 19, 2015 Share Posted February 19, 2015 (edited) Wisconsin Cambrian fossils in sandstone (aprox. 492 million years). Sharply defined rings. Very circular. Not irregular shaped like jellyfish. Any thoughts? Plus, If you can come up with a really good answer, you might get $500 Okay......The fossils aren't mine. They were found by amateur geologists Jerry Gunderson and Ron Meyer. They are part of a contest being done by the University of California Riverside. They are asking for people to prepare explanations for these fossil/geological features. And the best answer gets $500. (Or the best answers get to split the amount.) More details here with more photos, a video and descriptions. http://ringmaster.cs.ucr.edu/Rings.html They are looking at explanations to be submitted to their Reddit site. Here's observations they note about where the fossils were found and the size and depth of the rings. Ring diameters vary from about 2 cm to 11 cm, and the distribution of sizes appears to be a normal distribution. Cross sections through the rings (photos 3-5 above) suggest that if the rings formed at the seafloor (as opposed to within the sediment) they did so as grooves or ditches into the seafloor, rather than being upstanding circular structures such as the walls of a lunar crater. The grooves have apparently subsequently been infilled with sediment. Ring walls are 2-4mm wide and width is not obviously dependent on ring diameter – rather, it is related to what material the wall is cast in: rings cast by mud are narrower than those cast by sand. Rings extend down into the sediment as far as about 9 mm. Ring walls may have several layers of mud and sand within them – they were not necessarily filled up with sediment in a single episode of deposition. There is no indication of any structure preserved at the center of the rings. Ring walls are sharply defined compared to other structures in these rocks that are clearly animal burrows – hence the rings might have formed after the burrowing activity took place. Rings walls can be wider at the top of the ring than at the base, some even seem to have a slight bevel at the top. This is not the case in all rings. It is possible that some rings were originally slightly tilted relative to the sediment bedding because in several cases sections cut across the rings suggest that one side is slightly “higher” in the sediment than the other. It is not clear that this pattern existed at the times the rings formed: it could be an artifact that happened as the sediment experienced compaction. Ring distribution appears to be random on surfaces in which ring density is high. But where rings are distributed less densely, they tend to be dispersed, meaning their centers tend to be further apart from one another than chance would suggest. This may mean that rings forming at or near the same time were less likely to form in areas already occupied by other rings. The same rock unit is found commonly in the area, but these structures are only known at a single quarry. The rocks from this quarry are distinctive in the way they split well along bed partings so it is possible that the rings occur elsewhere but have not been recognized yet. We do not know whether the rings formed at the seafloor, or whether they formed within the sediment after the layers containing them were buried. When viewed in cross section there is nothing obvious either beneath or above the rings that throws any further light on their origins. The only structures associated with their formation are apparently the rings themselves. Edited February 19, 2015 by Stocksdale Somewhere, something incredible is waiting to be known.–Carl Sagan Link to comment Share on other sites More sharing options...
fossilized6s Posted February 19, 2015 Share Posted February 19, 2015 I'll say it again "do not set your soda down on sandstone slabs, it will cause rings"! 1 ~Charlie~ "There are those that look at things the way they are, and ask why.....i dream of things that never were, and ask why not?" ~RFK ->Get your Mosasaur print ->How to spot a fake Trilobite ->How to identify a CONCRETION from a DINOSAUR EGG Link to comment Share on other sites More sharing options...
Stocksdale Posted February 19, 2015 Author Share Posted February 19, 2015 (edited) Good one. That's why we don't have nice things in the Cambrian And again these were not found by me..... They were found by the well-known amateur geologists Jerry Gunderson and Ron Meyer in a quarry in southwest Wisconsin. There's a lengthy video with more details about them here. http://ringmaster.cs.ucr.edu/Rings2.html A lot of interesting info in the video including an original folk song about the "Rings of Wisconsin". Edited February 19, 2015 by Stocksdale Somewhere, something incredible is waiting to be known.–Carl Sagan Link to comment Share on other sites More sharing options...
Stocksdale Posted February 19, 2015 Author Share Posted February 19, 2015 Limpet trace scars would be a good match. Here's a picture of modern ones. But I don't think any fossils of Limpet-like creatures that large have been found in the Cambrian. Somewhere, something incredible is waiting to be known.–Carl Sagan Link to comment Share on other sites More sharing options...
Wrangellian Posted February 19, 2015 Share Posted February 19, 2015 (edited) !!! That's a quirky little video.. All I can think is something like the above suggestion of something circular (organism) settling down onto the sediment, be it a jellyfish or whatever (no idea if they ever do that or have done it - perhaps feeding on something that lived on the seafloor?) OR, some kind of smaller organism on the order of a worm that burrowed in a circle... again, no idea why anything would do that, but there is that little fish today that makes elaborate circular (radial) patterns in the sediment as a display to attract a female, but I'm sure these people would have thought of these before and need something more to go on! Edited February 19, 2015 by Wrangellian Link to comment Share on other sites More sharing options...
Missourian Posted February 19, 2015 Share Posted February 19, 2015 Quite Ediacaran-like.... My vote would be for some kind of jellyfish impression or resting trace. Context is critical. Link to comment Share on other sites More sharing options...
Raggedy Man Posted February 19, 2015 Share Posted February 19, 2015 Perhaps they're remnants of bubbles. ...I'm back. Link to comment Share on other sites More sharing options...
Stocksdale Posted February 19, 2015 Author Share Posted February 19, 2015 I was thinking of something like bubbles at first. One thing that I should point out. The video suggests that the rings are depressions into the mud as opposed to a raised ring. The examples of raised rings are the "negative" mold formed in the sandstone above the rings. I had a crazy thought of something like a conodonts burrowing in the sand to form rings. Perhaps the most perfect circular rings were better at attracting a mate. Somewhere, something incredible is waiting to be known.–Carl Sagan Link to comment Share on other sites More sharing options...
finderskeepers Posted February 20, 2015 Share Posted February 20, 2015 (edited) .https://www.livingoceansfoundation.org/bait-grounds-ngeruktabel-rock-islands-palau/. I was wondering if it could be the vestige of a tube sponge colony or column coral or both like this photo shows. Edited February 20, 2015 by finderskeepers Link to comment Share on other sites More sharing options...
janislav Posted February 21, 2015 Share Posted February 21, 2015 I'm with the bubble crowd, although a "normal" distribution of diameter strikes me as unlikely for bubbles. Link to comment Share on other sites More sharing options...
Auspex Posted February 21, 2015 Share Posted February 21, 2015 I think they are resting traces, probably of soft-bodied, free-swimming organisms of radial design. The likely analog would be something like a jellyfish. "There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant “Try to learn something about everything and everything about something.” - Thomas Henry Huxley >Paleontology is an evolving science. >May your wonders never cease! Link to comment Share on other sites More sharing options...
piranha Posted February 21, 2015 Share Posted February 21, 2015 On 2/20/2015 at 4:36 PM, Auspex said: I think they are resting traces, probably of soft-bodied, free-swimming organisms of radial design. The likely analog would be something like a jellyfish. Another interesting interpretation suggests microbial colonies instead of medusoid traces: ABSTRACT: Enigmatic discoidal fossils are common in Neoproterozoic sedimentary sequences and in the stratigraphic record predate the first appearance of diverse Ediacaran fossil assemblages. Termed ‘medusoids’, these Neoproterozoic discoidal fossils have generally been interpreted as coelenterate-grade organisms implying a radially symmetrical body plan for ancestral eumetazoans. Analysis of exceptionally preserved discoidal fossils from the White Sea area, however, indicates that most of these discoidal forms represent colonial microbes. Localized pyritization, for example, reveals the presence of a conspicuous filamentous substructure in Ediacaria, whereas concentric rings, radial sectors and central structures in Cyclomedusa and Paliella compare directly with recent microbial colonies growing in a nutritionally heterogeneous environment. At least some Ediacaran discoids can be compared with extant concentric ring-shaped microbial colonies that grow in hypersaline microbial mats. Insofar as most of the remaining record of Ediacaran discoids can be attributed to the holdfast structures of non-radiate modular organisms, there is no support from the fossil record for identifying a radiate ancestry for the Metazoa. Grazhdankin, D., & Gerdes, G. (2007) Ediacaran microbial colonies. Lethaia, 40(3):201-210 OPEN ACCESS PDF Link to comment Share on other sites More sharing options...
luluboo1 Posted February 21, 2015 Share Posted February 21, 2015 Looks like a helical burrow that has been back filled and compressed. Link to comment Share on other sites More sharing options...
Auspex Posted February 21, 2015 Share Posted February 21, 2015 Another interesting interpretation suggests microbial colonies instead of medusoid traces... That's really interesting! I was postulating a mobile creature from what appears to be a 'worm' trace that bisects the ring impression below: "There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant “Try to learn something about everything and everything about something.” - Thomas Henry Huxley >Paleontology is an evolving science. >May your wonders never cease! Link to comment Share on other sites More sharing options...
Rockwood Posted February 21, 2015 Share Posted February 21, 2015 The video seems to indicate that they form on either sandy or mud surfaces. My thought is that that suggests something that is only marginally mobile feeding in it's preferred zone above the surface that gets beached at low tide. Perhaps a proto version of solitary rugosans that was medusoid but had a protective theca beginning to evolve. Link to comment Share on other sites More sharing options...
squali Posted February 21, 2015 Share Posted February 21, 2015 That's really interesting! I was postulating a mobile creature from what appears to be a 'worm' trace that bisects the ring impression below: ~.JPG Colony division? It's hard to remember why you drained the swamp when your surrounded by alligators. Link to comment Share on other sites More sharing options...
Scott S. Posted February 21, 2015 Share Posted February 21, 2015 I'm going to have to go with the ichnogenera Bergaueria with a low level of relief. This would be the accretion disk resting trace of anemones. Traces resembling the ones shown here are being heavily sought after in earliest Triassic deposits in an attempt to support the hypothesis that tabulate and rugosa corals resorted to abandoning their calcium carbonate skeletons and persisting in the elevated acidity marine environments temporarily. Once marine water conditions improved by the mid Triassic the began producing skeletons once again employing aragonite and adopting hexagonal skeletal morphological arrangements. George Stanley at u. Of Montana had conducted experiments with living corals raising the CO2 in the tank and watching the corals adapt to the increasing acidity by reducing and eventually abandoning their skeletons altogether. Once the acidity was reduced the corals regenerated their skeletons. I would be highly in support of this being an early medusoid or even transitionary coral holdfast trace 1 Link to comment Share on other sites More sharing options...
Tethys Posted February 21, 2015 Share Posted February 21, 2015 I am hoping to win the contest. I too think they are a resting trace, but I have a different ID for the tracemaker. The mode of preservation is very Ediacaran, which is rare elsewhere, but pretty common in Wisconsin strata up until the mid- Ordovician. Link to comment Share on other sites More sharing options...
Wrangellian Posted February 22, 2015 Share Posted February 22, 2015 I was going to ask (because if it said in any of the materials I missed it), do we know what the deposition depth was? I gather these occur on discreet horizons between deposition events, but were they exposed at low tide, or deeper than that and not exposed at all, and if so how deep? Link to comment Share on other sites More sharing options...
Stocksdale Posted February 22, 2015 Author Share Posted February 22, 2015 The group that is doing the contest did present a paper at GSA in October about these. http://www.researchgate.net/publication/267568334_Late_Cambrian_enigmatic_ring_structures_from_southwestern_Wisconsin_USA Somewhere, something incredible is waiting to be known.–Carl Sagan Link to comment Share on other sites More sharing options...
Stocksdale Posted February 22, 2015 Author Share Posted February 22, 2015 They provide side cut-always that show these forming between depositional events but I don't think they specifically say if the events are tidal or deeper. Perhaps they don't know. Somewhere, something incredible is waiting to be known.–Carl Sagan Link to comment Share on other sites More sharing options...
Auspex Posted February 22, 2015 Share Posted February 22, 2015 The sediment layer formed and was buried in an environment free of strong wave energy, in any case. "There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant “Try to learn something about everything and everything about something.” - Thomas Henry Huxley >Paleontology is an evolving science. >May your wonders never cease! Link to comment Share on other sites More sharing options...
Tethys Posted February 22, 2015 Share Posted February 22, 2015 The Sauk Sea is reconstructed as a shallow body of water that had long periods of fair weather and occasional violent storms, similar to hurricanes. Link to comment Share on other sites More sharing options...
Cole Posted February 22, 2015 Share Posted February 22, 2015 I like finderskeepers idea of it being a "vestige of a tube sponge colony" Cole~ Knowledge has three degrees-opinion, science, illumination. The means or instrument of the first is sense; of the second, dialectic; of the third, intuition. Plotinus 204 or 205 C.E., Egyptian Philosopher Link to comment Share on other sites More sharing options...
digit Posted February 23, 2015 Share Posted February 23, 2015 .https://www.livingoceansfoundation.org/bait-grounds-ngeruktabel-rock-islands-palau/. I was wondering if it could be the vestige of a tube sponge colony or column coral or both like this photo shows. Funny to see this image as I was with Andy when he took this photo a couple of weeks ago in Palau. Now there's a weird 'small world' syndrome for you. Even odder is that a different friend of mine just came across this link and sent it to me: http://www.thefossilforum.com/index.php?/topic/52588-wisconsin-cambrian-fossil-mystery/?hl=%2Brings+%2Bcambrian Synchronicity at its finest. Cheers. -Ken Link to comment Share on other sites More sharing options...
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