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Stromatolites


tracer

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stromatolitic bioherms of the Wilberns Formation, San Saba Member, in central Texas. Upper Cambrian.

post-488-12623924205579_thumb.jpg

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Is that a G.I. Joe hammer, or did they grow 'em that massive back then?

Muy cool!

"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!

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That is a very good example of algal colonies.

I had to look up what they actually were.

Welcome to the forum!

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the back-story to this is that tj fell in the river while i was taking pictures of the stromatolites.

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Man thats cool were you get the little hammer

Galveston Island 32 miles long 2 miles wide 134 bars 23 liquor stores any questions?

Evolution is Chimp Change.

Life is not about waiting for the storm to pass; it's about learning to dance in the rain!

"I like to listen. I have learned a great deal from listening carefully. Most people never listen." Ernest Hemingway

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Find of the Month?

Nothing in the rules that you have to store it indoors...

"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!

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Find of the Month?

Nothing in the rules that you have to store it indoors...

LOL very True! Nice find

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little rock

Arkansas

Galveston Island 32 miles long 2 miles wide 134 bars 23 liquor stores any questions?

Evolution is Chimp Change.

Life is not about waiting for the storm to pass; it's about learning to dance in the rain!

"I like to listen. I have learned a great deal from listening carefully. Most people never listen." Ernest Hemingway

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Arkansas

think about it. tj falls in the river, and is having a real "here and now" moment, whilst his father gazes in wonder at the fossilized remnants of cyanobacteria from half a billion years earlier. that sort of irony can't be fully appreciated without wondering why "kansas" and "arkansas" aren't pronounced the same. but really, i think that particular mason's hammer came from a pawn shop for like two dollars. and it is a big hammer, not a little hammer. the bioherms are big too. just how it is.

but if you're in little rock, leave and go to jessieville and look for crystals. that's what tj would do.

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tracer..... Nice find.... they baffle me really, how they form etc..... I found a couple of chunks of this in a quarry in Somerset and they are called cotham marble apparently.... I was told to get them cut and polished as they display ...''landscape like images''.. when sectioned and polished... so much so the victorians thought they captured a moment in time.... one day I will get them done as I need access to a propper saw etc.... and if you would like to see a photo of em in the raw, just ask.... heres a link to what they look like sectioned and polished.....

http://fossilsdirect.com/details.cfm?prodref=SP781

Cheers Steve... And Welcome if your a New Member... :)

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Whack off a big chunk of that and send it to me and I'll polish us up a piece.

I have some Montana stromatolite. And some Mary Ellen Jasper (stromatoloite) from the NEast. Both have completely different patterns from what you have.

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whilst his father gazes in wonder at the fossilized remnants of cyanobacteria from half a billion years earlier.

I have stromatolites in my area, here's a pic of one that resided in my angelfish tank:

post-1880-1262441256055_thumb.jpg

I've found lots of them since I learned to recognize them.

My question to you, the ever-skeptical Mr. t, is how do you know that's upper Cambrian? Aren't you in a cretaceous area? And stromatolites even exist today. I assumed that the ones I found were Mississippian in age, to match the formation. Could they actually be much older?

NEVER MIND, I finally RTFA, it was a Cambrian formation.

Edited by Ron E.
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well, i posed the hammer with the fossils for scale, but i definitely didn't whack off any chunks of the stromatolites. i felt like they were really cool and needed to be left as they were for others to enjoy for however long they can.

as far as how they form, i'm still no expert, and never will be, on the apparently fairly complicated subjects of primitive tiny "animals" and "plants" and the precipitation of calcareous micro-scale structural elements or "waste" products by them. i guess i'll go read some more on coccolithophores. when i drive on the west side of austin or san antonio and see the huge walls of limestone, my mind can't wrap itself around the scale of how all that, and the many feet of it still underground, was created on a micro scale by tiny critters, apparently in numbers close to what i consider infinity to represent. for me it's like looking out into the sky and attempting to contemplate the scope of the universe.

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My question to you, the ever-skeptical Mr. t, is how do you know that's upper Cambrian? Aren't you in a cretaceous area? And stromatolites even exist today. I assumed that the ones I found were Mississippian in age, to match the formation. Could they actually be much older?

actually, i'm in the holocene, but those fossils are nowhere near me. i would think that, if there's such a thing as an unqualified accurate statement in amateur paleofanatisy, it would be that stromatolite bioherms aren't reworked into the strata in which they're found, and therefore are the age of the strata. as far as how i get my info on the age of the Wilberns Formation, i get it the same way i get my info on the ages of all other formations - by just looking it up. if all the geological formations' birth certificates have been forged, then the joke's on me.

but the central mineral area of texas even has plutonic bedrock sticking way up in the air, so there's a fair amount of area there that's too old for any fossils at all. it's really sad to imagine a time before there were fossils OR video games. guess that's why nobody lived then - there wasn't anything to do.

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actually, i'm in the holocene, but those fossils are nowhere near me. i would think that, if there's such a thing as an unqualified accurate statement in amateur paleofanatisy, it would be that stromatolite bioherms aren't reworked into the strata in which they're found, and therefore are the age of the strata. as far as how i get my info on the age of the Wilberns Formation, i get it the same way i get my info on the ages of all other formations - by just looking it up. if all the geological formations' birth certificates have been forged, then the joke's on me.

but the central mineral area of texas even has plutonic bedrock sticking way up in the air, so there's a fair amount of area there that's too old for any fossils at all. it's really sad to imagine a time before there were fossils OR video games. guess that's why nobody lived then - there wasn't anything to do.

Yeah, I appended my comment. I have to learn not to comment before that second cup of coffee... :)

Texas is an amazing place, geologically speaking. The next time I'm down that way, I'll be the one covered in mud and dirt with the grin on his face.

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Guest N.AL.hunter

If anyone wants to see a lot of stromatolites and you live anywhere near Tennessee, Edgar Evans State Park located on Centerhill Lake not too far from Murfreesboro has them. Along the shoreline are many stromatolites. However, being a state park you can't collect them, but I suspect that if you had a small boat you could go along the shoreline and get out of the park bounderies and find some to collect.

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but if you're in little rock, leave and go to jessieville and look for crystals. that's what tj would do.

Me Too road trip.

It's to cool to break up. Thanks for the picture

Galveston Island 32 miles long 2 miles wide 134 bars 23 liquor stores any questions?

Evolution is Chimp Change.

Life is not about waiting for the storm to pass; it's about learning to dance in the rain!

"I like to listen. I have learned a great deal from listening carefully. Most people never listen." Ernest Hemingway

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Hey Tracer, thanks for the post on stromatolites. Enjoyed seeing some nice examples again. I too am bedazzled by the formation of those structures. Cant quite come to terms of something so primitive building such large structures.

But when you figure they had hundreds of millions of years to work out the process and hundreds if not billions of years to try different things--if only those dang little grazing creatures didnt keep showing up after their mass extinctions and if plate tectonics didnt keep moving things around and then subducting things on you we might have something the size of the great pyramids of Eqypt still in front of us and you wouldnt even wonder how they got that last block on top of the pyramid!! :phew: :fpc: Where's more of that holiday eggnog? Regards, Chris

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well, i posed the hammer with the fossils for scale, but i definitely didn't whack off any chunks of the stromatolites. i felt like they were really cool and needed to be left as they were for others to enjoy for however long they can.

as far as how they form, i'm still no expert, and never will be, on the apparently fairly complicated subjects of primitive tiny "animals" and "plants" and the precipitation of calcareous micro-scale structural elements or "waste" products by them. i guess i'll go read some more on coccolithophores. when i drive on the west side of austin or san antonio and see the huge walls of limestone, my mind can't wrap itself around the scale of how all that, and the many feet of it still underground, was created on a micro scale by tiny critters, apparently in numbers close to what i consider infinity to represent. for me it's like looking out into the sky and attempting to contemplate the scope of the universe.

Hmmmm, personally I would rather see them immortalized on one of my shelves, but each to his own. :)

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Stromatolites form when cyanobacteria remove CO2 from the surrounding water during photosynthesis. This raises the pH locally because that CO2 is dissolved as carbonic acid (H2CO3). With the raising of the pH, carbonates cannot stay dissolved, so they precipitate out as a layer that the bacteria grows on.

Brent Ashcraft

ashcraft, brent allen

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thanks. since i took an interest a while back regarding how fossils actually form, it has been interesting to read about the degree to which bacteria and their chemistry in reducing and oxidizing environments are involved, as opposed to the common concept that it's just permineralization through exposure to oversaturated mineral solutions.

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Thank for the posting, you made me remember

I left my stromatolite out side

Had to dig it out of a 20" snow bank

I like the little hammer

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Here's a slice of the stuff from the Eocene of Wyoming

post-423-12627349807279_thumb.jpg

Shown sort-of wet; someday I'll have it polished.

"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!

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