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ithilwenOn to the fossils!
The barn covers a large portion of the bank containing the fossil-rick ash deposit. Here the staff has set up a set of signs, showing the geology of the bank:
Beneath the foot-thick layer of volcanic ash is a layer of sand, containing less well-preserved fossils of animals which lived and died by the water hole in the years prior to the huge volcanic eruption. We'll see that layer later, when we venture back outside.
Now we're standing at the far end of the barn, looking back toward the entrance. The far end is where most of the excavation work to date has been done; you can see the skeletons in the lower right of the photo:
Skeletons in the foreground, bank in the background:
Earlier excavations removed the skeletons from the surrounding ash so they could be transported to other locations for detailed study. The current excavations are attempting to uncover the remains while leaving them in place:
An entire herd of animals, trapped together forever in death, all perfectly preserved. Most of the ones in this photo are rhinos, but the skeleton with the red 2 on it is a stallion from a small species of extinct horse.
A closeup of a young rhino:
A mare and foal:
Scientists think the small mare was standing over her dead foal when she expired.
The preservation is remarkable! Scavengers have torn apart a few of the skeletons, but most are perfectly intact. The last meal of many of the animals can be seen (in the visitor's center, they display the fossil skeleton of a crane; you can see the half-digested remains of a lizard in the crane's crop). Some of the adult female rhino skeletons contain fetal bones, showing the animals were pregnant at the time they died.
There are very few places in the world where such a complete fossilized snapshot of a single moment of time can be found. And when you look at the size of the ash bed yet remaining to be excavated, you wonder what else future scientists are going to discover here!
We've one last sight to see, back behind the rhino barn. Here the ash is gone, and you can see the sandy soil of the ancient water hole. There are fossils here as well, less well-preserved, but of many more species. Scientists are also excavating this area, as it gives them a good look at what lived in the region immediately before the volcano devastated everything:
The soil this scientist is scraping up so carefully will be sifted later, in the hopes of discovering small bone fragments and teeth:
So far, they've discovered fossil hedgehogs, mice, kangaroo rats, rhinos (of course), camels (of course), horses (of course), bone-crushing dogs, fruit-eating dogs 9found nearby, not at Ashfall itself), mammoths (also found nearby), and other critters. 12.5 million years ago, this waterhole was a busy place! You can see a relatively complete list here.
I hope you enjoyed this quick look at Ashfall Fossil Beds State Historical Park. I also stopped at the nearby town of Neleigh, which is home to the last fully operational 19th century flour mill found in the state. That was also interesting, but alas, I took no pictures of it. If you ever decide to do a road trip to the Black Hills or the Badlands, get off I90 and spend some time checking out the sights in northeast Nebraska. It will make for a longer, but much more interesting, road trip!
The barn covers a large portion of the bank containing the fossil-rick ash deposit. Here the staff has set up a set of signs, showing the geology of the bank:
Beneath the foot-thick layer of volcanic ash is a layer of sand, containing less well-preserved fossils of animals which lived and died by the water hole in the years prior to the huge volcanic eruption. We'll see that layer later, when we venture back outside.
Now we're standing at the far end of the barn, looking back toward the entrance. The far end is where most of the excavation work to date has been done; you can see the skeletons in the lower right of the photo:
Skeletons in the foreground, bank in the background:
Earlier excavations removed the skeletons from the surrounding ash so they could be transported to other locations for detailed study. The current excavations are attempting to uncover the remains while leaving them in place:
An entire herd of animals, trapped together forever in death, all perfectly preserved. Most of the ones in this photo are rhinos, but the skeleton with the red 2 on it is a stallion from a small species of extinct horse.
A closeup of a young rhino:
A mare and foal:
Scientists think the small mare was standing over her dead foal when she expired.
The preservation is remarkable! Scavengers have torn apart a few of the skeletons, but most are perfectly intact. The last meal of many of the animals can be seen (in the visitor's center, they display the fossil skeleton of a crane; you can see the half-digested remains of a lizard in the crane's crop). Some of the adult female rhino skeletons contain fetal bones, showing the animals were pregnant at the time they died.
There are very few places in the world where such a complete fossilized snapshot of a single moment of time can be found. And when you look at the size of the ash bed yet remaining to be excavated, you wonder what else future scientists are going to discover here!
We've one last sight to see, back behind the rhino barn. Here the ash is gone, and you can see the sandy soil of the ancient water hole. There are fossils here as well, less well-preserved, but of many more species. Scientists are also excavating this area, as it gives them a good look at what lived in the region immediately before the volcano devastated everything:
The soil this scientist is scraping up so carefully will be sifted later, in the hopes of discovering small bone fragments and teeth:
So far, they've discovered fossil hedgehogs, mice, kangaroo rats, rhinos (of course), camels (of course), horses (of course), bone-crushing dogs, fruit-eating dogs 9found nearby, not at Ashfall itself), mammoths (also found nearby), and other critters. 12.5 million years ago, this waterhole was a busy place! You can see a relatively complete list here.
I hope you enjoyed this quick look at Ashfall Fossil Beds State Historical Park. I also stopped at the nearby town of Neleigh, which is home to the last fully operational 19th century flour mill found in the state. That was also interesting, but alas, I took no pictures of it. If you ever decide to do a road trip to the Black Hills or the Badlands, get off I90 and spend some time checking out the sights in northeast Nebraska. It will make for a longer, but much more interesting, road trip!
no subject
Date: 2011-08-24 04:19 am (UTC)Strange that the sandy layers before the ash should have more species -- I wonder what the explanation is?
And yes, I did enjoy these two posts. :)
no subject
Date: 2011-08-24 12:32 pm (UTC)Strange that the sandy layers before the ash should have more species -- I wonder what the explanation is?
I think it's just the timeframes involved that account for the differences. The fossils in the sandy layers probably accumulated over hundreds of years, while the ones in the ash were deposited over the course of a mere few weeks' time. So if a species was rare in the area, or only a seasonal visitor, you'd be more likely to find its bones in the sandy layer than the ash layer.
One thing the scientists are really hoping to find in the ash eventually is the remains of a carnivore. Some of the skeletons show clear evidence of scavenger activity so they know carnivores were around, but so far none have been discovered in the ash layer. But there's lots more ash to excavate, so who knows what might turn up!
And yes, I did enjoy these two posts. :)
Why am I not surprised? :D There are some other fossil sites out in the Nebraska panhandle I'd like to see eventually, too; if you ever make it out this way, we can go on a big fossil-themed road trip!
no subject
Date: 2011-08-24 03:02 pm (UTC)It's always surprised me that the carnivores didn't show up in the ash layer; but yes, they would be very rare. It's been speculated the survivors may have stayed in caves, but gods only know what they did for an air supply that wasn't full of little razor-sharp pieces of glass.
. . . if you ever make it out this way, we can go on a big fossil-themed road trip!
*grin* I'd love that. If I ever have enough money, we can make plans!
no subject
Date: 2011-08-25 09:21 pm (UTC)*grin* I'd love that. If I ever have enough money, we can make plans!
We've got ourselves a date! :D