Are these structures Stromatolites?

[sarahbbgun]

I’ve been clearing out invasive vines from my neighborhood park/green space and came across these structures absolutely covered in fortunes spindle and green briar. 
 

I could see a little part poking out and wow I just had to uncover them. Could they be stromatolites? Or just layered ole weathered limestone boulders? 
 

My Google searches of stromatolites did turn up a few that resembled these structures. But only a few:) 

 

any thoughts are greatly welcomed! 

[Rockwood]

I see a few recognizable crinoid bits in the mix. It looks like a higher energy environment than one would expect to find stromatolites preserved in. Some of the more clearly stratified looking material may be stromatoporoid, but it will take closer study of a cleaned up facet to say for certain.

[FranzBernhard]

@Rockwood has a good eye and he is very probably right!

Do you have a high pressure washer handy or is this area too remote for such equipment?

Franz Bernhard

[sarahbbgun]

30 minutes ago, Rockwood said:

I see a few recognizable crinoid bits in the mix. It looks like a higher energy environment than one would expect to find stromatolites preserved in. Some of the more clearly stratified looking material may be stromatoporoid, but it will take closer study of a cleaned up facet to say for certain.

 

30 minutes ago, Rockwood said:

I see a few recognizable crinoid bits in the mix. It looks like a higher energy environment than one would expect to find stromatolites preserved in. Some of the more clearly stratified looking material may be stromatoporoid, but it will take closer study of a cleaned up facet to say for certain.

Wow thanks! One man from a Fb group told me that the fossils I’ve found from that park are “shock” fossil pieces. Shock from an impact nearby. They are like conglomerates of lots of little pieces of broken fossils. I myself haven’t seen any crinoids (not whole pieces) but maybe there are some on these structures.
 

Maybe something in these videos will help you get a better view. My phone is old and I do not have a steady hand. I tried to slow a few places down that may help. The top of the really dirty one is quiet wavy and lumpy with shallow holes. 
 

I’ll  be walking out there in a bit. I don’t have a way to take a pressure washer out there but I do have a scrub brush and can carry water from the creek:) 

[sarahbbgun]

38 minutes ago, Rockwood said:

I see a few recognizable crinoid bits in the mix. It looks like a higher energy environment than one would expect to find stromatolites preserved in. Some of the more clearly stratified looking material may be stromatoporoid, but it will take closer study of a cleaned up facet to say for certain.

Also  what is a “high energy area”? Thanks again! Never knew of the stromatoporoids! 
 

One picture of a stromatoporoid on Google kinda looks like this part I circled in red. What do you think? 

[sarahbbgun]

39 minutes ago, FranzBernhard said:

@Rockwood has a good eye and he is very probably right!

Do you have a high pressure washer handy or is this area too remote for such equipment?

Franz Bernhard

I wish I could get one out there! There is a home nearby. Maybe I can get up the nerve to ask to run a hose and pressure washer from their place. I can make it happen eventually. May just take a scrub brush and Dawn dish soap and use water from the creek  thanks! 

[sarahbbgun]

3 minutes ago, sarahbbgun said:

Also  what is a “high energy area”? Thanks again! Never knew of the stromatoporoids! 
 

One picture of a stromatoporoid on Google kinda looks like this part I circled in red. What do you think? 

Wait - I posted the wrong closeup oops

[sarahbbgun]

47 minutes ago, Rockwood said:

I see a few recognizable crinoid bits in the mix. It looks like a higher energy environment than one would expect to find stromatolites preserved in. Some of the more clearly stratified looking material may be stromatoporoid, but it will take closer study of a cleaned up facet to say for certain.

 

[Rockwood]

1 hour ago, sarahbbgun said:

Also  what is a “high energy area”?

 

1 hour ago, sarahbbgun said:

Shock from an impact nearby.

Well, I wasn't thinking quite that high. This look is often associated with some type of reef, and the debris that accumulates in wave dominated environments. Stromatolites are thought of as more of a quiet water construction where bacterial colonies can compete with the sedimentation rate. 

[sarahbbgun]

58 minutes ago, Rockwood said:

 

Well, I wasn't thinking quite that high. This look is often associated with some type of reef, and the debris that accumulates in wave dominated environments. Stromatolites are thought of as more of a quiet water construction where bacterial colonies can compete with the sedimentation rate. 

Ah I get it. And here was more of a low water energy swampy environment. Is it Cyanobacteria only that helps form the stromatolites?? Im getting together some of the rocks from that area to see what you think about those. Many have these white lines everywhere. Some are very layered. Did you see the videos? Thanks for the help! 

[Rockwood]

14 minutes ago, sarahbbgun said:

Did you see the videos?

Yes, but I'm afraid it didn't help much. My mind works better with things that don't move. 

Never could pick a shark tooth from the waves either. 

[Rockwood]

1 hour ago, sarahbbgun said:

Many have these white lines everywhere. Some are very layered.

If a fresh flake of it were to somehow get dislodged you could look at under a lens. 

[sarahbbgun]

On 1/29/2023 at 1:19 PM, Rockwood said:

Yes, but I'm afraid it didn't help much. My mind works better with things that don't move. 

Never could pick a shark tooth from the waves either. 

I hear ya! I didn’t get a chance to go yesterday. When I do I’ll get some better stills LOLOL  thanks! 

[Mahnmut]

You do not need soap to clean those, soap is only for removing fat. Pure water should be enough out there.

Best Regards,

J

[sarahbbgun]

On 1/29/2023 at 9:48 AM, Rockwood said:

I see a few recognizable crinoid bits in the mix. It looks like a higher energy environment than one would expect to find stromatolites preserved in. Some of the more clearly stratified looking material may be stromatoporoid, but it will take closer study of a cleaned up facet to say for certain.

Hi there! I'm finally posting the follow up pictures HAHAHA. The weather cleaned em off   What do you think? stromatolites? 

[Rockwood]

7 minutes ago, sarahbbgun said:

What do you think? stromatolites?

I sort of doubt it, but I'm not the one to say it isn't.