RWA3006
Cave Dweller
Member since March 2009
Posts: 4,210
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Post by RWA3006 on Apr 22, 2021 12:33:05 GMT -5
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Post by RickB on Apr 22, 2021 18:43:21 GMT -5
A jigsaw puzzle with interlocking pieces
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,210
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Post by RWA3006 on Apr 22, 2021 18:52:22 GMT -5
I see a scorpion in the lower half.
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Post by fernwood on Apr 22, 2021 22:29:15 GMT -5
Very interesting article pertaining to gastroliths. Quote-- Rocks That Journeyed From Wisconsin To Wyoming Millions Of Years Ago May Have Dinosaurs To Thank Scientists Hypothesize Sauropods Swallowed The Rocks Native To Wisconsin That Were Discovered In Wyoming By Elizabeth Dohms-Harter Published: Thursday, April 22, 2021, 6:55am In a research article published In Terra Nova in February, a possible explanation for the 1,000-mile journey of these rocks is that they were carried in the stomachs of sauropods who picked them up in Wisconsin as a way to help digest their food. Joseph Frederickson, director of the Weis Earth Science Museum at the University of Wisconsin-Oshkosh, said the study was completed in the Morrison Formation — a rock unit in the western part of the United States that dates back about 150 million years to the Late Jurassic Period. The Jurassic Period dates from 200 million years ago to 146 million years ago. This formation contains fossils of dinosaurs such as the allosaurus, stegosaurus and the long-necked sauropods. Although the Morrison Formation is primarily comprised of mudstones, there is evidence of other rocks not native to the area. "Occasionally, you're going to come across these really hard, rounded cobbles made of quartzite and other hard rocks that really look out of place," Frederickson said. Prior to this study, scientists thought these cobbles were gastroliths, stones swallowed by animals to help them digest their food. Frederickson said unlike mammals, dinosaurs couldn't chew their food and digest it, so they swallowed rocks to help grind down the plant materials. But the question still remains: How do we know those rocks came from Wisconsin? Frederickson said it's because those rocks are a particular color and texture that's found in the state, namely red quartzite. "Red quartzite is unique because a lot of the sites around that are out west aren't that deep red color," he said. "Here in Wisconsin, however, we actually have red quartzites that everyone in the state could go visit at Devil's Lake State Park." These rocks are named Baraboo quartzite and are about 1.65 billion years old, Frederickson said. The distinctive color comes from the iron contained in the rocks. To test whether the quartzite found in Wyoming was in any way similar to rocks in Wisconsin, scientists studied their isotopes and found the age of the isotopes in the Wyoming quartzite matched better to the Baraboo quartzite than to the rock closer to Wyoming. --End Quote Full article: www.wpr.org/rocks-journeyed-wisconsin-wyoming-millions-years-ago-may-have-dinosaurs-thank?fbclid=IwAR3tQTUDlWKyQ9jHuAuJgUYuSD8McHSvG2EnXKre22DPxCA13hMOmUGE990
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Post by fernwood on Apr 23, 2021 6:19:52 GMT -5
This could be a significant discovery. Traditional thought has been that there were never dino's in WI. I have always thought that was strange, considering how the climate changed over the years.
Yes, the Baraboo Quartzite is very unique. I have several large pieces. It is found not only by Devil's Lake, but also in NW WI near Rice Lake.
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,210
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Post by RWA3006 on Apr 23, 2021 8:13:31 GMT -5
That's really interesting fernwoodIt doesn't surprise me when you consider that the time span is so vast that probabilities escalate considerably for all kinds of things to have happened.
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stewdogg
spending too much on rocks
Member since January 2020
Posts: 388
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Post by stewdogg on Apr 23, 2021 9:18:59 GMT -5
That is a very interesting read/thought fernwood, thanks for posting it. I have a good amount of Baraboo quartzite in the yard right now and will be driving some chunks out to jasoninsd at the end of next month, so now there will be some non digested Baraboo quartzite almost in Wyoming...
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Post by jasoninsd on Apr 23, 2021 9:37:43 GMT -5
That is a very interesting read/thought fernwood , thanks for posting it. I have a good amount of Baraboo quartzite in the yard right now and will be driving some chunks out to jasoninsd at the end of next month, so now there will be some non digested Baraboo quartzite almost in Wyoming... Whoot Whoot! I've already been negotiating with the "powers that be" and trying my best to advocate great weather that week! I guess we'll see how much pull I have with that one when the time comes! LOL
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,210
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Post by RWA3006 on Apr 23, 2021 10:00:16 GMT -5
That is a very interesting read/thought fernwood, thanks for posting it. I have a good amount of Baraboo quartzite in the yard right now and will be driving some chunks out to jasoninsd at the end of next month, so now there will be some non digested Baraboo quartzite almost in Wyoming... Ha, you gave me a wicked thought. Send me a box of tumbled Baraboo and I'll plant it with coprolite where paleontologists are working in southern Utah. kidding
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stefan
Cave Dweller
Member since January 2005
Posts: 14,095
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Post by stefan on Apr 23, 2021 15:00:32 GMT -5
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,210
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Post by RWA3006 on Apr 23, 2021 16:45:00 GMT -5
Glad it arrived OK. Now comes the big question if there's treasure inside when you cut that stuff open! This stuff is hard to predict if it will be awesome or just blah inside.
What did Forrest say? ...like a box of chocolates, you never know what's....
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stefan
Cave Dweller
Member since January 2005
Posts: 14,095
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Post by stefan on Apr 23, 2021 17:04:07 GMT -5
OH I have a very good feeling. Moved some stuff around in the shop and should have room to get the saw setup and running this weekend.
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Brian
fully equipped rock polisher
Member since July 2020
Posts: 1,506
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Post by Brian on Apr 23, 2021 18:19:46 GMT -5
Looks like some nice turds you got! That one in the second picture with the red streaks going through it is interesting.
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,210
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Post by RWA3006 on Apr 23, 2021 20:20:09 GMT -5
I fired up the saw last night to slab this piece and after the first slice I thought it was one of those bland turds that wasn't worth slabbing. I put a light on it to better determine it's quality and was surprised to find it was a "twiggy" piece. Occasionally I encounter a coprolite where the dino didn't chew his food as well as mother taught him and the result is the turd has "ghosts" of twigs within. When you realize that pine boughs were a prominent part of their menu it's reasonable to identify these ghosts as cross sections of undigested twigs. I counted up to seven twig cross sections in some of these slabs. They are harder to identify from the poor phone camera.
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,210
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Post by RWA3006 on Apr 23, 2021 20:20:46 GMT -5
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,210
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Post by RWA3006 on Apr 23, 2021 20:34:52 GMT -5
For those of you who are wondering where the twig ghosts are we will need to tune your eye a bit so you'll know what you are looking for, so here comes the tutorial. Remember, these have been partially digested so they aren't always obvious, thus I call them ghosts.
I look for several different patterns that are markers for twig ghosts. The most obvious are circular shapes where I can actually see the growth rings of the wood. That's what first clued me into this phenomenon.
The next pattern is more subtle, but is compelling if you've ever done much with pine limbs. When you break dry limbs to make a campfire you'll notice the wood breaks into certain patterns, especially if it's old weathered conifer pieces. This is especially applicable to twigs about the diameter of your fingers. I often see a triangular pattern where the wood split longitudinally are left wedge shapes.
Let's study the next photos so we can get a feel what to look for....
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Brian
fully equipped rock polisher
Member since July 2020
Posts: 1,506
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Post by Brian on Apr 23, 2021 20:37:36 GMT -5
For those of you who are wondering where the twig ghosts are we will need to tune your eye a bit so you'll know what you are looking for, so here comes the tutorial. Remember, these have been partially digested so they aren't always obvious, thus I call them ghosts. I look for several different patterns that are markers for twig ghosts. The most obvious are circular shapes where I can actually see the growth rings of the wood. That's what first clued me into this phenomenon. The next pattern is more subtle, but is compelling if you've ever done much with pine limbs. When you break dry limbs to make a campfire you'll notice the wood breaks into certain patterns, especially if it's old weathered conifer pieces. This is especially applicable to twigs about the diameter of your fingers. I often see a triangular pattern where the wood split longitudinally are left wedge shapes. Let's study the next photos so we can get a feel what to look for.... You read my mind! I was just about to ask how to identify those twigs. Some of the others you have posted seemed more obvious. If you hadn't said the last batch contained twigs, I don't think I would have noticed. Looking closely, I can almost see a different shade, circular ring in the top right and bottom left of what I am guessing are the twigs.
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,210
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Post by RWA3006 on Apr 23, 2021 20:37:52 GMT -5
Here's a coprolite slab where a lone twig is obvious. If you had it in your hand you would be able to see growth rings in the wood.
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,210
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Post by RWA3006 on Apr 23, 2021 20:39:44 GMT -5
This slab has four ghosts in it. Can you see the subtle triangular patterns in them?
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,210
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Post by RWA3006 on Apr 23, 2021 20:46:43 GMT -5
Those of you who've split firewood are familiar with how pieces tend to come apart into triangular chunks. I'll bet many of you have observed old posts or logs will naturally deteriorate into these shapes. Here's some petrified wood limbs that naturally fell apart at some point.
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