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Dinosaur Dig Field Reports
September 28, 2000
Camp Internet sent a team of three adults and four students out in the field to visit a Dino Dig site in Fruita, Colorado. The dig was sponsored by the Dinosaur Journey facility operated by the Museum of Western Colorado in Grand Junction through their Dinosaur Museum program located in Fruita. Dr. Rod Scheetz was the host paleontologist and docents Walt and Don assisted.
The Mygatt Moore Quarry in Rabbit Valley, right at the edge of the Colorado/Utah state line, is the site where the paleontologists are working. It was once a lake bed that gathered bones swept down from taller mountains that surrounded it, and is now filled with white and buff layers of shale sediment. Donning ventilated hats or working under the shaded tarps at the Dig, the crew went to work to dig up the bones of an Allosaurus, a fierce meat-eating dinosaur that once lived in the Ancient Southwest. Here on the northern edge of the Colorado Plateau, there have been hundred of dinosaur fossils found right in a small area, a sign of what life was like over 148 million years ago.
Morning Journal Entry 10am
We were lucky at the Dino Dig today - not just because we found real 148 million year old bones and teeth, but also because the weather was just right for a Dino Dig. Yesterday, when we arrived at 4600 feet above sea level in Fruita, it was a scorching heat wave …. this morning we find ourselves working under a welcomed cloud cover at the Mygatt Moore Quarry with Dr. Rod Scheeetz as our excavation leader. He has been at the site several hours before us, uncovering the most recent level of excavation as it is buried with rubble following every day's work to protect the finds.
Who first found this site ? Was it a scientist out looking for dinosaur bones ? Dr. Sheetz explains that this site was stumbled upon by two families our for a hike in 1984 who saw the bones protruding from the rock and called the Museum of Western Colorado to alert them to the find. Situated on Bureau of Land Mgt (BLM) lands, the Museum has been excavating the site ever since.
The interpretive display at the quarry explains that Apatosausrus, Allosaurus, Camarasaurus, Camptosaurus, Brachiosaurus, Stegosaurus, Mymorrrapelta (first found here at Mygatt Moore - hence mymo in the name), Diplodocus, and Ceratosaurus bones and traces have been found right here in this area of Rabbit Valley. The area's bones date from the Upper Jurassic, 148 million years ago. Wow !
The bones our Camp students are uncovering are from an Allosaurus, considered a small dinosaur but it would have had hind legs alone taller than a full grown man. There was an already partially excavated shoulder bone that was about 4' long and a vertebrae that was a foot across - both were clearly huge specimens compared to human bones. That vertebrae was bigger around than a human adults waist - and it was just one of many vertebrae in its spine. More bones encased in plaster were awaiting removal to the laboratory.
How did we dig ? Well, each amateur paleontologist on the Camp team was provided with a cool tool kit folded up in a canvas divider- we had a stiff brush to sweep away the rock, a delicate brush to clean out around the bones with, and a set of picks and screw drivers to pry away the rock. Sometimes we had to use the ice pick to pry away the layers of shale, and it then crumbled fast and easily. But sometimes, as it crumbled, bone and tooth fragments were revealed that were too brittle to rescue. But the 8 year old on the team did find the tooth of a young Allosaurus that Dr. Sheetz explained would have been all black if it had been an adult, but it had a yellow center meaning its dentin had not yet filled in which was due to its young age. And another student, aged 15, found a round shoulder bone about the size of a salad plate and over 3" thick that was packed up and taken back to the lab. The stone was light, the bones, teeth and plant fossils were dark making them easy to see .. when they did appear. It was wonderful to help the Museum proceed with its research working side-by-side with their team. After each find, Dr. Scheetz marked its location on his gird map, noting its distance from the wooden and string markers that outlined the quadrant under study on the site.
Lunch Break, 12 noon
At noon we headed into the shade and were served a tasty plant-eater lunch - lemonade, fruit salad and cheese sandwiches. A tiny lizard was our local host for lunch, watching us and wondering what WE were doing in HIS home !! Families come out to the site all summer long to participate in their own Dino Dig. Enjoy a camp lunch and then head back to the museum to watch the paleontologists work in the lab and tour the exhibits.
Afternoon and Evening 1-9pm
In the afternoon we headed back to the Museum to bring Dr. Scheetz online for the Camp's classroom chat. Students from Lake Arrowhead and Roosevelt classrooms joined us for a lively afternoon Trail Guide Chat you can see in our archives. Then in the evening, the Family Dino Night took place and families from SEVEN schools joined us from classroom and home computers to learn more about Dinosaurs in the Ancient Southwest. Dr. Scheetz was a great live and online Trail Guide and we thank him for his efforts. The Family Dino Night chat is in the archive too for you to review.
Down below us in the museum during the chat, robotic animated dinosaurs are roaring, gnawing, spitting, and acting up like wild creatures! Overlooking the dino display is the Museum's paleo lab with researchers hard at work cleaning, preparing, and cataloging the finds from the quarry. But not everything found in the Mygatt Moore Quarry are bones or teeth … dino dung called coprolites is also a sought after find ! The Museum packs it up and ships the dung to an Ichnologist, Dr. Karen Chin, in San Diego for study.
Why study Dung ? Dung tells scientists what the dinosaurs were eating, which tells them what grew there in their lifetime, and that tells us all what the climate was like. In this part of Colorado, right at the northern edge of what is now the Colorado Plateau of the Four Corners, 148 million years ago the environment was not a swamp of swimming dinosaurs, nor was it a dry desert. The climate then was similar to what the California Central Valley is like now - around 20" of rain a year with conifers (pine needle trees), horsetails, cycads, gingko and ferns growing around small lakes, in valleys, and up the mountain sides. The shale we were digging through was filled with black plant matter - twigs, branches, leaves - some of which had been eaten and discarded by ancient dinosaurs !
One of the other special discoveries at the Quarry have been five new plants never found before that are relatives of other plants known to have grown during the Jurassic. Other discoveries have been turtles and alligators! All signs of Jurassic life in the Ancient Southwest.
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