Algae-On-A-Stick

A lot of the trips I remember - from my teenage years before I left to get an education - started with my dad coming back from a trip to the wilds of Utah, excited because he learned about some new place to find rocks. Not too long before I left, it happened again.

My dad had been deer hunting with his friends in the foothills above "The Park". I found myself enlisted as a pack mule hauling these rocks up steep shale hills.

My dad had stumbled across a deposit of rocks that I believe are totally unique. Only my dad, and maybe a paleontologist, would have stopped long enough to notice them. And similarly, only my dad, and a paleontologist, would have understood what he was looking at. Maybe not even a paleontologist. I haven't found one yet who does. It appears to me that most people, even paleontologists, immediately fall into the trap of thinking, "Oh Ja! I know what that is!"

But they don't.

The Park is the local name for a long, gentle valley that stretches from Soldier Summit in the west to the top of Nine Mile Canyon in the east. The north side advances through increasingly higher foothills until it fades into the Uinta Basin and eventually the Uinta Mountains. Every other range of mountains in the West run north and south. The Uinta Mountains run east and west. Sometimes, we just have to be different in Utah.

Part of the problem could be that rockhounds collect a well known rock that looks a little bit like Algae-on-a-Stick. One well known site, not far from where my dad discovered these rocks, is called "Birdseye Marble". A rockhounding site says this about it.

This lake deposited a sequence of sediments that formed rocks known as the Flagstaff Formation. Although these rocks are technically a limestone, the building stone industry has termed this deposit a "marble." The rocks are rich in algal ball structures commonly known as "birdseyes."58 to 66 million years ago, the whole area was a fresh water lake called Lake Flagstaff. One of the rocks found in that formation is called "Birdseye Marble".

This lake deposited a sequence of sediments that formed rocks known as the Flagstaff Formation. Although these rocks are technically a limestone, the building stone industry has termed this deposit a "marble." The rocks are rich in algal ball structures commonly known as "birdseyes."

These rocks have sometimes been misidentified as oncolites. Here's the geological definition of an oncolite (Wikipedia):

Oncolites are sedimentary structures composed of oncoids, which are layered structures formed by cyanobacterial growth. Oncolites are very similar to Stromatolites, but, instead of forming columns, they form approximately spherical structures. The oncoids often form around a central nucleus, such as a shell fragment, and a calcium carbonate structure is deposited by encrusting microbes.

My fossil is clearly a column, not a sphere. Oncolites are typically much smaller - "with an average size of less than one inch" according to worldatlas.com. Mine are usually at least ten times larger. One thing is certain. My dad's A-o-a-S fossils are not oncolites!

One way to see the difference is another unique feature of A-o-a-S: the globular structure of the outer layer. Just looking at it, it's easy to see the similarity with living organisms commonly found in swamps today. What you can see in those swamps today is real living "algae on a stick". (OK ... more like 'moss' ... I was looking for a catchy name.) I've seen lots of swamps and shallow lakes with sticks and reeds encrusted with green goo sticking out of the water. They look exactly like these rocks ... except that they are living, green plants. These green gobs didn't form in layers with the gradual deposition of calcium by cyanobacteria over long periods of geological time. They formed in just a few years in a swamp. My fossils look like brown versions of the same thing -- except that they are rock.

If my "Algae-on-a-Stick" fossils didn't form as oncolites, how did they form? A living green mass on the outside of a stick is fragile and normally couldn't be turned into a silicified fossil. The algae and moss would disintegrate long before that happened. Since oncolites form gradually over time, the outer layer is quite different and oncolites don't form along the length of sticks and reeds. They form as spheres. Column shaped stromatolite fossils also exist, but they are the result of gradual growth on the top surface of a cyanobacteria mass. Living stromatolites can be found in Australia and also in Utah's Great Salt Lake.

The reason you find "dinosaur bone" silicified fossils instead of fossilized dinosaur flesh is that only the bone is durable enough to survive being buried and turned into stone. (Very fragmentary samples of actual fossilized dinosaurs have been found and they are the crown jewels of the paleontology world.)

Blue Forest wood from Eden Valley in Wyoming is an exception. It's often covered with fossilized moss and algae, but it's compressed and looks like a layer of dirt. (Until you try to scrape it off. Then you realize that it's part of the fossil. Trust me. I've done it.) The outer layer of Blue Forest wood was also deposited on a stick in just a few months or years. And Blue Forest is also noted for the detailed and accurate replacement of the wood, except that my A-o-a-S is even more detailed and more accurate. So, the way Blue Forest wood was formed is probably quite similar.

I have an idea about how A-o-a-S formed and I'd like a paleontologist to give it serious consideration.

Here's my idea.

The Burgess Shale fossils are extremely rare replacements of incredibly old organisms. They were created in a process that I believe also resulted in the A-o-a-S fossils. Burgess Shale fossils are replaced soft-bodied creatures from the Cambrian - almost ten times older than A-o-a-S and older than almost all fossils. Fossils like the ones from the Burgess Shale are found in only a few places in the world. The Canadian Rockies and China are the only places I know of.

Scientists believe that the soft Burgess Shale soft bodied organisms that managed to be preserved as fossils due to a unique geological event that initially buried them. The theory is that something that might be called a gentle underwater landslide occurred and living creatures were very gently covered with fine silt drifting down through still water - so fine and gentle that the soft=bodied creatures were left whole and perfect. An event like that could also have preserved the A-o-a-S.

I tell everyone that "I'm not a great rockhound. That was my dad." He wasn't a paleontologist either. I can't afford to subscribe to the academic journals that might have more clues, but I was able to acquire a PDF written by a scientist, Malcolm Weiss. who has documented similar looking fossils associated with central Utah's ancient Lake Flagstaff in “Oncolites, Paleoecology, and Laramide Tectonics, Central Utah” (The American Association of Petroleum Geologists Bulletin, V. 63, No. 5, May, 1969). The fossils documented in this paper are much smaller and less well preserved, but they make the point that roughly similar fossils do exist, even though they might have been created differently. Familiarity of oncolites in geology may have caused Weiss to identify his fossils that way, especially since a poor replacement forces a best guess instead of a definite conclusion.

The fossils documented in this paper are much smaller and less well preserved, but they make the point that such fossils exist to people who might be able to help. I occasionally send one of these fossils to someone with the plea, "Treat this seriously. Get back to me about it." So far, it has been a mission of futility.

There's a legendary story in geology like this. Sometimes, the best discoveries are the result of work by people who are not dedicated specialists. The most revolutionary and important new idea in geology is "Plate Tectonics". It was originally discovered and proposed by a meteorologist named Alfred Wegener. Scorn and ridicule was heaped on Wegener during his life. "What a stupid idea to think that the whole surface of the Earth is floating around on magma like wood chips on molasses. And the guy isn't even a geologist! He's a glorified weatherman!"

I don't claim to be a Wegener or a geologist. I was only lucky enough to inherit these rocks from a great rockhound: my dad. But they deserve serious consideration and I'm going to keep working to get it for them.

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Addendum (June 2026):

A friendly visitor caused me to make another search for something similar to my A-o-a-S. I found it! FossilEra.com has recently listed a polished slab for sale that could be a genuine A-o-a-S. (But they're STILL calling it a stromatolite. IT'S NOT A STROMATOLITE.) I know my dad traded some for other rocks at various shows that he went to after he retired. I've given away pieces. FossilEra states, "Little is know about the specimen other than it was found at Old Lake Uintah of Carbon County, Utah." There has been some core drilling to explore the formations around there recently. I doubt that was the source of the rock they have, however.

FossilEra should contact me. I did contact them once but nothing came of it. If they're nice this time, I might be willing to talk to them.

FossilEra also dates their slab to the Eocene, 45-50 million years ago -- less than half the age of dinosaurs and less than a tenth the age of most fossilized stromatolite. (Mary Ellen jasper is fossilized stromatolite.) That's close enough for government work. BUT THEN, they switch gears to fossil stromatolites again which are typically hundreds of million years old. They already admit that their fossil is ten times younger. Don't they proofread their own stuff?

The slab they have for sale isn't a really good one because whatever is in the middle isn't a stick or reed. But if someone did a microscope slide, their eyes would probably pop out at what they saw. The sticks and reeds in the middle are the most perfectly preserved that I have ever seen.