Drive Trackway Site
December of 1999, while going for a Sunday morning drive, William
Kurtz, a paleontology student at The University of Colorado, made a
remarkable discovery. While
, which is west of
, he was amazed to see what he thought were dinosaur tracks.
It was right above the road and visible, at least to a trained
person. Kurtz reported the
find to Donna Engard, the curator of the Dinosaur Depot.
Together they went up to survey the tracks that he had seen.
rock wall along
as it appeared before
excavation began. How many
people, over decades of time, had looked at this and seen only rocks?
February of 2000, with help from the city of
City in closing
to work in secrecy, volunteers from the Garden Park Paleontology
Society began to excavate the trackway site.
This involved as many as eighteen volunteers working with
hammers, chisels, crowbars, picks, shovels and wheelbarrows to clear
the tons of rock covering the tracks and other fossils.
days it was Cold...
days it was Hot!
is the discovery track after a lot of preparation work with hammer and
chisel. Now you see
you don’t! After one too
many blows with the hammer, it fell off into Bill Kurtz’s arms and
was taken to the Dinosaur Depot where it is on display.
far, none of the others have fallen off.
early April of 2000, the amazing find was announced to the press and
was reopened. From then on
the work became talking to visitors about what we were doing, as well
as chipping away at more rock. Since
we were working most weekends, many repeat visitors came often to
watch the progress.
Stone, executive director of the Garden Park Paleontology
Society, and Donna Engard, curator of the Dinosaur Depot, show
off their new hammer drill for use on the Skyline Drive
Trackway site. The
drill was purchased with a $2,500 gift from the
and Park Company,
here represented by their marketing director, Nancy Weeks.
The drill made the work on the site go much quicker.
Stone uses the new hammer drill on the Skyline Drive Trackway site to
remove the overlying rock layers and expose the dinosaur tracks.
order to preserve the value of the tracks for scientific study, molds
were made of the “type set” tracks as well as some of the other
unusual specimens that were found.
Here, Donna Engard, curator of the Dinosaur Depot, and
volunteer Steve Martin apply layers of latex and burlap.
After this dried, the mold was removed and taken to the
Dinosaur Depot where it was filled with plaster to create a cast of
is a picture of the tracks that became the “Descriptive Set” which
was used to define the type of dinosaur tracks that we found.
After many measurements of individual tracks and the stride
length between them, as well as detail description, it was determined
to be an Ankylosaur track known as Tetrapodosaurus
As you can see, the front foot or manus has 5 toes, while the
back foot or pez has 4 toes.
These tracks were made during the early Cretaceous Period,
approximately 107 million years ago.
During that time this area was on the edge of the Western
Interior Seaway. A group
of dinosaurs were walking side by side through the mud along the edge
of an estuary, probably eating the plants.
The tracks were then filled in by sand and plant debris, which
hardened to preserve them as casts of the actual tracks.
After the sediments were deposited, the walls of the basin were
raised by the
uplift that tilted the rocks
on edge. This explains why
they bulge out instead of being a depression like one normally thinks
of as a “footprint”.
order to study the tracks, one of the most important details is exact
measurement of each one. We started with traditional methods to gather
every imaginable measurement of size and dimension of each track, plus
stride angles and lengths between the tracks.
Here are three ways in which this feat was accomplished.
A. A one-meter square
metal frame marked in ½ meter squares.
Part of a forty-meter by 4-meter grid marked in meter
squares made out of non-stretch string.
C. Since the tracks
bulge out, we used a tape measure in conjunction with very large home
made calipers that could measure around the bulge instead of adding
the extra height to our measurements.
few of the other fossils that were found during excavation of the
trackway were: A. Tree
Mystery object that looks like a clam, but isn’t one.
to the Bureau of Land Managment (BLM) National Technology Lab we were
also able to use very modern data using photogrammetry, which is the
process of making precise measurements by means of photography, to get
data for 3-D records of the tracks. Here Neffra Mathews of the BLM
sights the camera, Donna Engard provides shade so she can see, Judy
Stone steadies the tripod against the wind, and
keeps detailed records of the shoot.
Jon Stone supervises while Tom Noble of the BLM marks the next
black and white “targets” are reference points at known distances
used in the final analysis of the measurements.
Mathews also arranged for
Moore and Chess Neff of 3-D Scan of Grand Junction to do a
three-dimensional laser scan of the trackway.
measurements to the “ targets “ from known points along the road
were taken to add to the data for a precise photographic map of the
images show photographic and laser scan data combined in different
forms. Each image has the
distortions of the angle of the actual Trackway corrected to a flat
image for pinpoint measurement of each track.
is a topographic line map of the tracks.
is a false color image that reflects the topography of the tracks with
a 10 centimeter color break.
image shows topographic lines on a color photograph.
to a generous donation from the Cañon City Rotary Club, we were
able to purchase these explanatory signs and some safety
improvements including a fence to separate visitors from the traffic
Trackway as seen on
April 10, 2002
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