There are lots of dinosaur tracks here in East-Central Utah. Many of them are imprinted on sandstone surfaces, but another type - commonly called "coal tracks" - are sometimes found on the roofs of tunnels in the many coal mines in this area.
The formation of coal tracks began when, millions of years ago, a dinosaur walked in a swamp, leaving indentations in the shape of his feet in the decomposing vegetation. In most cases the footprints were later filled in with more vegetation which was indistinguishable from the other deposits around it, and that was the end of that. In some cases it happened that flowing water would bring in sand to fill the indentations. Those sand filled indentations had the potential to become coal tracks.
Later, due to the forces of plate tectonics, the swamp subsided and was covered with many more layers of vegetation and sand. From pressure and heat deep under the surface the vegetation was changed to coal, and the sand became hard sandstone. Much later this area was uplifted until the ancient swamp deposits are 6000 to 10,000 feet above sea level. Erosion cut deep canyons through the various layers. In the walls of these canyons ancient history is revealed as layers of sandstone and coal.
Today, miners search for the layers of coal, called seams. They dig tunnels into the seams, removing the coal from bottom to top. They occasionally notice the sandstone that filled an ancient dino footprint hanging from the ceiling of a seam, still preserving the shape of the foot. Often they collect them. There are a lot of homes in Price that have "coal tracks" in their yards, or used as doorstops. The CEU Museum has the world's finest collection of the tracks.
Last summer we were exploring the walls of a canyon very near our RV camp. There was a small coal seam exposed. It was about two feet high. The coal was a lot softer than the surrounding sandstone, so weathering had removed about three feet of the face of the coal, leaving an overhanging sandstone ledge. We noticed a lump of sandstone projecting from the bottom of the ledge. The lump was back under the ledge and appeared to extend back into the uneroded coal. It looked like it could be one toe of a coal track. We excavated some of the coal around the lump and it still looked like it could be a track. We mentioned the track to a few people, but then it was time to return to Florida for the winter.
When we returned to Utah this spring we checked - the lump was still there. We removed some more coal from around it and it still looked like a track, so we reported it to the Museum and asked them if they would like to have the track, if that was what it was, for their display. They said they would. We enlisted the help of the Utah Friends of Palentology, a club of which we are members, to collect the track.
The big event occurred on 6/8/99, which was Peg's 60th birthday. A total of ten people, including us, showed up. Only two people could get under the overhang to work at a time. It took about two hours to totally uncover and remove the lump. It really was a track!!! We used a very long chisel and a heavy hammer to remove the surrounding coal and then to break the track free from the sandstone above it. It took four people to carry the track, in a stretcher made for the occasion, to a truck.
The pictures below show some features of the adventure. One thing we haven't previously mentioned is that there was a very large rock which had broken loose from it's original location high in the canyon wall and lodged about ten feet directly above where we had to work to excavate the track. Nobody was sure that pounding on the coal below would not dislodge the rock, and it was the subject of many wary glances, but nobody let it keep them from working, and the rock stayed in place.
The track is in the Museum lab to be cleaned up - there is still a lot of coal adhering to it. When it is ready it will be added the Museum collection. We intend to make a plaster copy of the track which we will bring back to Florida, so we too can have a dinosaur footprint in our yard.
The general expert opinion is that the track was made by an Hadrosaur, a medium sized vegetarian dinosaur that mostly walked on it's two hind feet. The track is 26 inches wide, 20 inches from heel to toe.
If you just have to know more - under the pix we have added three links to other Web sites dealing with coal tracks. The first site is brief and interesting, the mine it describes is about six miles from here. The other sites are more technical(boring?).
Links to Sites About Coal Tracks
Map of Coal Tracks in Coal Mine Roof
A long technical description of Coal Tracks.
An early (1924) paper.
