Day 43: Dinosaur National Monument

Thursday
Sometimes there is so much packed into a day, or even an hour, that it takes me several days to work out what I want to say about it. Our visit to Dinosaur National Monument (DNM) was one such occasion.
We had camped at Red Fleet because it was close to the DNM, so it w as a reasonable drive to the park. DNM isn't just about the dinosaurs, it is also a wild area known as Split Mountain, so we were combining two places in one visit.
We arrived at the visitor center and watched a Short video, mostly about the historical background to the park, which  goes back to a guy called Douglas, who was a paleontologist back at the turn of the century (1900's that is). It was him who discovered the fossil bed that is the Dinosaur Quarry.
After a look round the VC we drove the short distance to the Dinosaur Quarry. This is a building that entirely encloses the side of a small cliff, about 40ft high and 150ft long. Inside there is a gallery floor and the ground floor, one entire side of the building is the sandstone strata that is called the Morrison Formation. Although it is a layer of sandstone, because of the major mountain building that went on about 30 million years ago the start is now almost vertical about 80 degrees from horizontal.
The area was discovered by Douglas when out walking he found large fossilized dinosaur bones. The sandstone layer has soft shale like material on either side, so over a few years Douglas and his team removed the soft material leaving the thirty foot thick sandstone layer, they were then able to remove some 300 tons of dinosaur bones, which were shipped back east to Pittsburgh. However is stead of completely removing all the bones the last few feet of the sandstone layer were left intact, complete with all the remaining dinosaur fossils. This became the basis for the Dinosaur Quarry exhibit.
when we entered the building we were on the top gallery floor and cold look directly across at the rock wall, where we could see that it was almost entirely covered with many hundreds of fossil dinosaur bones, not all neatly wired up like in a museum , but still fixed into the sandstone layer that had held them for the last 149 million years. It took some time to work out that although we were looking at an almost vertical wall that wall had been a horizontal ground until the rock was forced upwards, so it was almost a birds eye view of a dinosaur graveyard. Scientist working there reckoned that this particular place was at a bottleneck in a river and after a particularly bad drought then flooding that many large dinosaurs, both dead and alive, were washed into this bottleneck, which was made worse by all the carcases and bones. This area rapidly silted up, preserving the large number of bones which could then quietly fossilize away. However the action of washing them down the river meant that the bones became separated and mixed up. Paleontologists had worked hard to identify different animals and their bones and a handy guide enabled us to pick out the giant bones of Diplodocus, Allosaurus, Camarassurus and Stegasaurus, though it took some time, even with the guide diagrams.
It is easy to get into details, however the whole scene was quite fascinating, even surreal, that here before us was a window onto a world that was so incredibly different to our world today, when these bones were part of real animals that we can only see and know through the painstaking forensics of scientists. What a wonderful experience this was. We sort of just stood and looked for quite a few minutes trying to take in the scale of it all.

Of course we asked all sorts of interesting (to us) questions of the rangers and had a look outside to see the sandstone layer disappear into the East, the had lunch before embarking on part two of the DNM - Split Mountain. It is what is says it is, a mountains that has been split in two by the Green River. The interesting point is that a normal erosion cycle would have taken the river on the path of least resistance, which is round the mountain, instead it has eroded away the mountain forcing a pathway through the middle of it. The reason apparently is that before the mountain building that went on 30 million years ago the Green River had already carved a pathway through the rock that lay above the current land surface, which has now been completely eroded away, so that when the uplift came the river was constrained to the river bed it had already  made, so continued to erode away across the middle of a mountain, laveaving the locally famous feature of Split Mountain. The end result is a failry impressive river canyon and a very pretty drive. Because we could not leave the road we were unagble to see the more spectacular parts of it, but we saw enough.
To complete our fascinating adventure we drpped into Golden Corral again for their steak buffet, which was scrummy.