Ichnofossil chondrites, or crinoids?

[Wxman]

I posted this image in the prep thread and I was widely stated to be an Ichnofossil of infilled burrows. I really don't want to be "that guy" that questions expert opinions, but I'm curious; the burrow seems to have attached branches and areas of tiny "grassy" masses adjacent to it. Could they be crinoid segments/branches and pinnules? I have seen photos of chondrites that have the same kind of appearance. I include 3 of my photos, including one through the eyepiece of my scope, and one internet photo of crinoid pinnules. 

Thanks. I'll happily accept your opinions, go away now, and not be a pest any further. 

 

  

[Tidgy's Dad]

Always worth querying. 

There's definitely something weird going on there. 

But I'm not sure what. 

[Wxman]

@Tidgy's Dad

I kind of thought so. But I'm totally willing to hear that I'm imagining things 

[ClearLake]

Yes, there are tubular shapes of different sizes in your specimen, but look closely at yours and then at the crinoid picture you posted.  Other than the general shape, there is no similarity. Crinoid arms, stalks, etc are made up of many connected segments which you can see in the photo you posted. Nothing like that is visible in the pieces you picked up. I think burrows or feeding traces are much more likely for your piece. 

[Wxman]

@ClearLakeFair enough. I totally agree about the segments. This stuff was on exposed intertidal coastline; a pretty rough environment. The "grassy" fine fibrous patches must be pretty tough. Is that normal for burrows? I'm just trying to learn here, and value input. 

[westcoast]

I tend to agree with questioning the burrows idea. On the upper part of the first 2 pictures there is clear segmentation on both the larger piece and the smaller 'offshoots'. Unfortunately preservation and weathering are not ideal. I would try to break off a piece to look at a slightly fresher surface.

[Rockwood]

I wonder if the segmentation was a feature in the deposit of organic material that was being consumed. Perhaps something like a big tasty coprolite, or maybe a sponge was home to some tiny creatures ? 

[Wxman]

@westcoast I'm glad my questioning was not off base, and that others see it as curious as well.  

Last night I put it under the microscope and used a dental pick to scrape through one of the smaller branches to see if there was any kind of structure or segmenting under the oxidized(?) surface layer. There doesn't appear to be. As @Mahnmut stated in my other thread, the consistency of the infill is similar to the matrix. So I guess burrows they are. I was surprised that the segmenting could be as uniform as that, and yet be just deformed infill. I'm also surprised that the small "grassy" patches would infill so effectively as to be that well preserved and stable.   As a newbie, I have much to learn, and I appreciate this forum and it's members for their insights. Thanks for your input. 

Andy. 

[Wxman]

@Rockwood I'm not sure. But they are cool looking, and bizarre under the microscope. 

[abyssunder]

I can see trace fossils there,  but I'm not 100% sure. There might be.

Nice specimen, that's sure.

[Wxman]

@Rockwood my initial thought was perhaps a plant like horsetail because of the segments and grassy sections. I know nothing of the intricacies of burrowing creatures so I have to trust the generally expressed school of thought here. 

[Rockwood]

7 minutes ago, Wxman said:

@Rockwood my initial thought was perhaps a plant like horsetail because of the segments and grassy sections. I know nothing of the intricacies of burrowing creatures so I have to trust the generally expressed school of thought here. 

It's not unimaginable. Without the preservation of the vascular ribs it may not be provable though. I feel confident that the smaller features are not plant fossils.