[Mile-marker 9]
From the Fruita interchange on I-70, the overpass leads north into the
town of Fruita, and Colorado Highway 340 leads south about 2½ miles to
the West Entrance of Colorado National Monument. One mile south we cross
the new bridge over the Colorado River; the old bridge formerly
connecting Fruita with the Monument may be seen half a mile upstream.
Just south of the new bridge we see sandstone on the left and green
shale on the right, both part of the Burro Canyon Formation. The high
hill on the left is made up of brightly colored siltstones and mudstones
of the Brushy Basin Member of the Morrison Formation capped by the basal
sandstone of the Burro Canyon Formation. On the southeast side of this
hill is another bronze plaque set in a masonry monument, similar to the
one at Riggs Hill (fig. 39), commemorating the discovery and removal in
1900 by Elmer S. Riggs of a skeleton of the immense dinosaur
_Apatosaurus excelcus_ Marsh. (See figure 23_B_). About 1¾ miles
northwest of the new bridge is the Fruita Paleontological area discussed
on page 50.
Just south of the hill, the highway curves gently to the left across a
relatively flat surface of the Morrison Formation. To the right may be
seen good exposures of the Entrada Sandstone, at the north end of which
curbstones were quarried from thin beds of the white Moab Member for use
in some of the parking areas along Rim Rock Drive. Some of the beds are
ripple marked[36] from wave action along ancient beaches or within
ancient lagoons. Some ripple-marked curbstones from this quarry may be
seen in the parking area at Red Canyon Overlook, and elsewhere in the
Monument.
As we approach the Monument we see that to the left the rock strata are
bent downward toward us along what geologists call a monocline (see
figs. 27 and 30), but to the right may be seen cliffs of dark
Proterozoic rocks surmounted by slopes of the red Chinle Formation and
cliffs of the buff Wingate Sandstone capped by the lowermost beds of the
resistant Kayenta Formation. The bent and broken rocks ahead are well
shown in figure 33.
About 1½ miles south of the Colorado River we reach the T-intersection
noted previously—at the end of the trip from Grand Junction through The
Redlands to the West Entrance of the Monument—and we are ready for our
trip through the Monument.