9,000-year-old rock art discovered among dinosaur footprints in Brazil

[admin]

Ancient hunter-gatherers created rock art next to dinosaur footprints in what is now Brazil.

9,000-year-old rock art discovered among dinosaur footprints in Brazil : Read more

 

[akiprev]

"dinosaur tracks, which date to the Cretaceous period (145 million to 66 million years ago)."
How these dinos' tracks weren't obliterated by erosion in mere thousands years is beyond me.

 

[dglens]

That's because they've only been there thousands of years. Why can't they see the obvious... That the two species coexisted.

 

[akiprev]

That's because they've only been there thousands of years. Why can't they see the obvious... That the two species coexisted.

But how can eminent scientists and publications publish such a nonsense? It's a matter of common sense, let alone the established rates of the rock erosion, that such imprints can't last any so long.

 

[nino82]

That's because they've only been there thousands of years. Why can't they see the obvious... That the two species coexisted.

I am not a geologist, and so I can't prove you wrong, but I would think the dino tracks would have to be older since they would have been imprinted/made on softer soil or mud which then had to harden over some time period before the humans could paint on the spot where the prints were made. I don't think a human could paint directly on soft soil or mud right after an animal made a foot print, but only on a hard surface like a rock, which would take years for the mud to harden into first. Based on a quick google search, the footprints were preserved because sediments and other materials fell on the footprints and were able to preserve them and protect them from erosion (until eventually the overlaying sediment did erode away, more recently, to reveal the foot prints).

 

[akiprev]

Based on a quick google search, the footprints were preserved because sediments and other materials fell on the footprints and were able to preserve them and protect them from erosion (until eventually the overlaying sediment did erode away, more recently, to reveal the foot prints).

Hm, I can't imagine that the overlying sediments could have eroded leaving these tracks discernible. Of course they would have coalesced with the underlying surface in any longer tracts of time.

 

[nino82]

Hm, I can't imagine that the overlying sediments could have eroded leaving these tracks discernible. Of course they would have coalesced with the underlying surface in any longer tracts of time.

You are probably right in 99% of cases, but maybe in a small fraction of situations the sediment doesn't alter the footprint, if it is made of a more erodible material than what the footprint is made out of, such that the footprint remains after the overlaying sediment gets eroded away. Similar to how you can see tall rock mounds or boulders sitting on top of narrow pieces of rock, due to the surrounding rocks/sediment eroding away (like the rock at Kannesteinen Vågsøy, Norway).

 

[diversemark]

I am not a geologist, and so I can't prove you wrong, but I would think the dino tracks would have to be older since they would have been imprinted/made on softer soil or mud which then had to harden over some time period before the humans could paint on the spot where the prints were made. I don't think a human could paint directly on soft soil or mud right after an animal made a foot print, but only on a hard surface like a rock, which would take years for the mud to harden into first. Based on a quick google search, the footprints were preserved because sediments and other materials fell on the footprints and were able to preserve them and protect them from erosion (until eventually the overlaying sediment did erode away, more recently, to reveal the foot prints).

You're correct that dinosaur tracks are typically preserved due to sedimentation and subsequent hardening of the substrate. When dinosaurs walked on soft mud or sediment, their footprints would leave impressions that, over time, could be filled with additional sediment or minerals, eventually solidifying into rock. This process, known as fossilization, can take thousands to millions of years depending on the specific conditions.

 

[akiprev]

You are probably right in 99% of cases, but maybe in a small fraction of situations the sediment doesn't alter the footprint, if it is made of a more erodible material than what the footprint is made out of, such that the footprint remains after the overlaying sediment gets eroded away. Similar to how you can see tall rock mounds or boulders sitting on top of narrow pieces of rock, due to the surrounding rocks/sediment eroding away (like the rock at Kannesteinen Vågsøy, Norway).

I still can't imagine how these prints could be discernible after the sediments allegedly eroded away. This rock doesn't look like aver having any subsequent sediment on it. Even otherwise, the meeting surfaces clearly wouldn't retain their reliefs.