KODELS CANYON FAULT, looking northwest across mouth of Fruita Canyon from point on Rim Rock Drive just described in text. Here, along a normal fault dipping steeply northeastward, the 350-foot cliff of Wingate Sandstone at upper left has been sheared and squeezed into only a few feet of broken rock overlain by a steep slope of the Kayenta Formation covered by piñon and juniper. The thinner cliff at right is the Entrada Sandstone which belongs high atop the cliffs at left. Book Cliffs form distant skyline at right. (Fig. 31)
If you doubt that [figure 31] shows a fault, a glance at [figure 32] in the next major canyon eight-tenths of a mile to the northwest should convince you. Here, on the northwest side of Kodels Canyon, the Wingate was not thinned but was rent completely asunder by the vertical Kodels Canyon fault ([fig. 32]). Kodels Canyon is not readily accessible to visitors.
The Lizard Canyon monocline, Kodels Canyon fault, and other structures are clearly shown in the stereoscopic pair of aerial photographs in [figure 33].
Another structural feature within the Monument is the Glade Park fault ([fig. 8]), which lies mainly south of the Monument but just cuts across the south end of No Thoroughfare Canyon in the latest addition to the Monument. It is well shown both from the air and the ground in figures [58] and [59]. It is unique among all the major faults in the area in that the rocks south of the fault subsided with respect to those on the north side.
KODELS CANYON FAULT, looking northwestward across canyon of same name. Base of Wingate cliff on left is just about opposite the top of the Wingate on right. Here, nature was kind to the geologist, for the vertical displacement (rise of left side with respect to right side) is virtually the thickness of the Wingate Sandstone—about 350 feet. The Wingate on the right is lighter colored than that on the left seemingly because rockfalls removed desert-varnish-coated rocks and exposed the true color of the sandstone. (Fig. 32)
GEOLOGIC STRUCTURES AT FRUITA ENTRANCE TO COLORADO NATIONAL MONUMENT. The stereoscopic pair of aerial photographs may be viewed without optical aids by those accustomed to this procedure, or by use of a simple double-lens stereoscope, such as the folding ones used by the armed forces during and after World War II. Geologic details may be identified by comparing photographs with the geologic map, [figure 8]. If viewer is unable to see stereoscopic pairs in three dimensions, looking at either photograph alone will convey a good idea of the geologic structure. The monocline near top of the photographs may be seen on the right-hand side of the highway in [figure 43]. Photographs taken in 1937 by U.S. Soil Conservation Service, hence, alinement of then unpaved Colorado Highway 340 differs from the paved present highway. (Fig. 33)
At this point in our story it might be well to point out that the folding and faulting of the rocks just described occurred when thousands of feet of younger rocks covered the area. Additional folding and faulting, drainage changes, and gradual removal of the overlying rocks occurred during the remainder of the Tertiary and Quaternary Periods, as will be discussed further.