The northeastern edge of The Needles proper can be seen from Squaw Flat (fig. 49), but the true character of The Needles can be appreciated better from the air (fig. 50). You cannot get far into The Needles without traversing part of The Grabens, so we will consider them together. An aerial oblique view (fig. 51) shows The Needles in the foreground and The Grabens in the middle background. As shown on the map (fig. 1), you can hike into The Needles and The Grabens from Squaw Flat, but let us make the trip using a four-wheel-drive vehicle and several short hikes.

Ordinary passenger cars now can go 2¾ miles west of Squaw Flat to Soda Spring, at the east base of Elephant Hill, but beyond Soda Spring four-wheel-drive vehicles should be used. Some people conquer the hill in dune buggies or on motorcycles, but this is considered quite dangerous. Both sides of this short (1¼ miles) but formidable hill have switchback curves too sharp to negotiate in the regular manner, so special driving techniques must be followed. On the east side, you must drive out on a flat rock, jockey back and forth until turned completely around, then proceed up the hill. On the west side, you descend a 40-percent grade to a shelf, back down a narrow stretch of about 30-percent grade and back sharply to the left onto a flat rock, then go forward again. On the return trip the whole procedure is carried out in reverse order.

West of Elephant Hill, the road reaches a Y, at which you must turn left on a one-way road; the right-hand road is for later one-way return to the Y. Why the left-hand fork is one way soon becomes apparent, for the road leads into a narrow shallow graben, called Devils Pocket (fig. 51), between rock walls, and is barely wide enough for one car. After about 2 miles the graben widens out into a beautiful spot called the Devils Kitchen, which contains several picnic tables tucked into shady recesses in the sandstone walls. This is the starting point for two trails leading southward by different routes to Chesler Park, from which other trails lead to Druid Arch or back to Squaw Flat.

From the Devils Kitchen, the road turns abruptly westward for about half a mile to another Y in about the middle of Devils Lane, one of the larger grabens and one of two whose entire length is traversed by roads, as shown on the map (fig. 1). Only the left fork is a two-way road, so let us take the left fork 2¾ miles southwestward to the next road junction. About halfway down Devils Lane, a fault crossing the graben has created a narrow steep ridge appropriately called SOB Hill, because the road over it creates a challenge that some vehicles fail to meet on the first attempt!

The next road intersection is now shown on the map (fig. 1) as a sharp turn leading southwest to Ruin Park and Beef Basin. The abandoned left fork (not shown) leads east into Chesler Park. This park, shown in figure 50 and near the bottom of figure 51, is a beautiful natural meadow of several hundred acres fenced by a natural wall of needles and containing a central island of needles. Because of vehicular damage to meadow vegetation, the National Park Service found it necessary to close the road. To reach Chesler Park now, vehicles must go right a short distance to the Chesler Canyon turnoff, then left about half a mile to a parking area. From here, a ½-mile hike east through the narrow Joint Trail gets us to the south side of Chesler Park, where we join the abandoned road to reach the northeast corner of the park and the trails into The Needles proper (fig. 1).

This change adds 1¾ miles (one way) to the hike to Druid Arch, making the round trip about 11½ miles. At the old trailhead, near the northeast corner of Chesler Park, is a sign proclaiming the need for rubber-soled shoes and water, and I strongly support these admonitions, for much of the hike is on bare smooth sandstone and includes steep slopes and generally dry waterfalls. The hike should not be attempted by anyone not in good physical condition, and it should not be undertaken alone; two or more people should travel together.

As shown in figure 52, the trail to Druid Arch from Chesler Park starts out on bare Cedar Mesa Sandstone marked by a succession of rock cairns, two of which are visible and without which the trail would soon be lost. The trail drops rapidly down into Elephant Canyon, which is then followed southward 2 miles to the arch. This canyon has cut through the Cedar Mesa into the underlying Rico Formation, and much of the canyon is quite narrow and steep sided, as shown in figure 53. Although much of the Rico consists of red beds laid down above sea level by ancient streams, the trail crosses several thin beds of dark-gray hard limestone containing fossil marine seashells and ancient sea anemones whose original calcium carbonate parts have been locally replaced by jasper (red iron-bearing silica). When at last the weary hiker makes the steep climb out of the canyon and rounds the final bare-rock curve, the sudden and striking view of Druid Arch (fig. 54) seems worth every bit of the effort—at least it was to me and my hiking companion.

After my friend and I hiked to Druid Arch and after the length of this route was increased to a round-trip distance of 11½ miles, a new route was constructed having a round-trip length of only 8½ miles. This new trail starts at the end of the passenger-car road at the east edge of Elephant Hill, goes 1¼ miles southwest to join an older trail in Elephant Canyon, then follows this canyon 3 miles south to the arch.

After returning to our vehicle west of Chesler Park and backtracking over SOB Hill to the intersection in the middle of Devils Lane, let us proceed northward on a one-way road to and beyond the Silver Stairs for a closer look at Devils Lane and other grabens to the west and for a look at the confluence of the Green and Colorado Rivers. But first let us pause and reflect upon the possible origin of The Grabens.

Geologists have different opinions as to just how grabens and complex systems of joints have formed, but all seem to agree that tensional forces were involved. Some think that solution of salt and gypsum from the Paradox Member of the Hermosa Formation by ground-water movement allowed the brittle Cedar Mesa Sandstone and other overlying rocks to sag, producing tension cracks and faults. Others believe that removal of the salt and gypsum occurred by plastic flowage toward the Meander anticline (see p. 108 and fig. 61), whose axis follows the Colorado River southwest from The Loop, past the confluence, and to and beyond Spanish Bottom. Some suppose that compaction due to the weight of the abnormally thick pile of sedimentary rock underlying the area may have caused the sagging, cracking, and faulting. The rock deformation may have resulted from a combination of these and possibly other things, of course, but whatever the cause, the resulting features are very striking. There was room to show only two of the named grabens within the park on the map (fig. 1), but all are shown in figure 51, and several appear in figure 59. A diagramatic cross section of a typical graben is shown in figure 55. The tension faults shown in figures 55 and 56 are called normal faults, in contrast to faults formed by horizontal compression, which are called reverse faults (figs. 75, 76).

The Grabens range in width from about 7 or 8 feet at the north end of Devils Pocket to nearly 2,000 feet at the south end of Red Lake Canyon, but the average width is about 500 feet. The floors of The Grabens are covered by soil and grass, but the displacement along the faults is believed to approximate the height of the walls—nearly 300 feet. That The Grabens are of fairly recent origin is attested by the fact that most of the walls are vertical fault faces showing little sign of erosion (fig. 57); that no through drainage has yet been established in Cyclone Canyon, which is a series of basins with low divides between; and that several pre-existing streams were interrupted or diverted by the faulting.

Now let us continue our journey northward along Devils Lane. Just before reaching the Silver Stairs we may wish to pause long enough to take in the distant view to the northwest toward Junction Butte and Grand View Point. (See frontispiece.) After descending the steep Silver Stairs in a narrow cleft between rock walls, we reach another intersection: a two-way road continuing northwest goes to our destination, and a one-way road turning right returns to Elephant Hill via part of Elephant Canyon (fig. 58).

About 2 miles to the northwest we cross the north end of Cyclone Canyon, the largest graben. It contains a road 3½ miles long and is well worth seeing. About one-half mile from the south end, an old trail follows Red Lake and Lower Red Lake Canyons to the Colorado River across from Spanish Bottom (figs. 1, 61).

From near the north end of Cyclone Canyon (figs. 1, 59), we drive west three-fourths mile to a parking area and hike one-half mile to an overlook for a spectacular view of the confluence of the Green and Colorado Rivers (figs. 59, 60) and of the northern part of Cataract Canyon (fig. 61). These and other canyons are discussed in the next chapter.

Canyons of the Green and Colorado Rivers

We have discussed two of the three major topographic divisions of the park—the high mesas and the benchlands—and there remains to consider the third division—the canyons of the mighty Green and Colorado Rivers and some of their tributaries. After we discuss a few features common to both rivers, we will take up the details of each river.

A glance at the map (fig. 1) shows that above the confluence both rivers are very crooked and contain many loops, or meanders, the most striking of which are Bowknot Bend of the Green River (fig. 62), several miles north of the park, and The Loop of the Colorado River (fig. 74). In contrast, the main stem of the Colorado River below the confluence is considerably straighter. Not apparent on the map are the facts that the crooked rivers above the confluence have very gentle grades and are free from rapids or falls, whereas a few miles south of the confluence the main stem plunges into Cataract Canyon—the steepest and wildest reach of the river, containing 64 rapids. These differences are partly explicable on the basis of the geologic structure and character of the rocks through which the rivers have cut. Above the confluence, the soft strata dip gently northward, so in flowing generally southward the two rivers are cutting “against the grain,” which tends to impede their flow and thus reduce their grades. Below the confluence, the hard limestones of the Hermosa Formation lie relatively flat for several miles and then begin to dip gently southward, thus allowing the river to cut “with the grain” and therefore drop more rapidly.

The quiet, smooth waters above the confluence permit power boating between the towns of Green River, Utah, and Moab during part of the year, whereas the rapids below Spanish Bottom, 3½ miles below the confluence, restrict river travel to float trips using sturdy boats or rafts.

Above the confluence, a so-called Friendship Cruise is run each year during the Memorial Day weekend. Participants tow their own power boats on trailers to the town of Green River, and after the boats are launched, facilities are available at nominal cost for transporting cars and boat trailers to Moab to await the arrival of the boats. Although some high-powered speedboats are reported to have made the run down the Green River to the confluence then up the Colorado River to Moab in a few hours, the trip for most boats requires 2 to 7 days.

Trips by power boats, including jet boats, can be arranged from either Green River or Moab. Some passengers from Moab return by jeep from Lathrop Canyon via the White Rim Trail, and some from Green River return on land via the Horsethief Trail. Many prefer the quieter float trip down to the confluence, with return to either town by a prescheduled power boat, and some more adventurous souls float through the rapids of Cataract Canyon all the way to Lake Powell.

In the spring of 1972, a 93-foot 150-passenger stern-wheeler (fig. 69) began passenger service on the Colorado River from just above Potash to the foot of Dead Horse Point and return (Lansford, 1972).

Entrenched and cutoff meanders

Meanders such as those above the confluence generally are formed by streams flowing in soft alluvium consisting of clay, silt, and sand, such as along the Mississippi River below Cairo, Ill. But there is no soft alluvium along the Colorado and Green Rivers, so how did these meanders form? They probably attained their serpentine shape while cutting in softer, younger material, which long ago was removed by erosion, and then continued to cut their crooked channels down, until they created the deep rock-walled canyons in which they now flow as “entrenched” meanders.

Meandering streams tend to shorten their lengths from time to time by cutting through narrow walls between adjacent loops, leaving abandoned horseshoe-shaped channels or lakes. In most of the United States these are known as oxbows or cutoff meanders, but in the desert Southwest they are commonly called by the Spanish term “rincon.” Cutoffs are common along soft alluvial channels such as the lower Mississippi River valley but are rare along channels whose meanders are entrenched into hard rock. Thus, there have been many natural (and several manmade) cutoffs along the lower Mississippi during historic times, but the most recent ones along the Green and upper Colorado Rivers probably occurred a million or so years ago, during the Pleistocene Epoch (figs. 65, 80).

Mark Twain served several years as an expert riverboat pilot on the Mississippi River during which several cutoffs took place. Chapter 27 of his “Life on the Mississippi” contains sage references to both natural and artificial cutoffs and concludes with a few good-natured jibes at geologists in particular and scientists in general:

Therefore the Mississippi between Cairo and New Orleans was twelve hundred and fifteen miles long one hundred and seventy six years ago. It was eleven hundred and eighty after the cutoff of 1722. It was one thousand and forty after the American Bend cut-off. It has lost sixty-seven miles since. Consequently, its length is only nine hundred and seventy-three miles at present.

Now, if I wanted to be one of those ponderous scientific people, and “let on” to prove what had occurred in the remote past by what had occurred in a given time in the recent past, or what will occur in the far future by what has occurred in late years, what an opportunity is here! Geology never had such a chance, nor such exact data to argue from! Nor “development of species,” either! Glacial epochs are great things, but they are vague—vague. Please observe:

In the space of one hundred and seventy-six years the Lower Mississippi has shortened itself two hundred and forty two miles. That is an average of a trifle over one mile and a third per year. Therefore, any calm person, who is not blind or idiotic, can see that in the Old Oölitic Silurian Period, just a million years ago next November, the Lower Mississippi River was upward of one million three hundred thousand miles long, and stuck out over the Gulf of Mexico like a fishing rod. And by the same token any person can see that seven hundred and forty-two years from now the Lower Mississippi will be only a mile and three-quarters long, and Cairo and New Orleans will have joined their streets together, and be plodding comfortably along under a single mayor and a mutual board of aldermen. There is something fascinating about science. One gets such wholesale returns of conjecture out of such a trifling investment of fact.

Green River

Much more has been written about the Green River and the main stem of the Colorado than about the Colorado above the confluence (the former Grand River), because all but one of the early float trips began on the Green. The first reports concerning Powell’s memorable voyages of 1869 and 1871 were his articles published in Scribners Monthly during 1874 and 1875 followed by his formal 1875 report “Exploration of the Colorado River of the West and Its Tributaries.” As pointed out by Porter (1969, p. 21), however, Powell’s narrative

is written as if everything chronicled therein occurred during the first trip. Events which actually occurred in 1871 and 1872 are reported as happening in 1869. There is no mention of the personnel of the 1871-72 party, nor is there an indication that there even was a second trip. The engravings illustrating the report were made from photographs taken by Beaman and Hillers between 1871 and 1874, but this fact is not noted.

For these reasons, Porter’s account contains Powell’s diary of the first (1869) trip and many of the missing photographs, plus his own beautiful color prints. Much more complete and accurate accounts of the 1871 voyage than those of Powell, including many of the photographs taken by Beaman and Hillers, were given by Dellenbaugh (1902, 1962), who was a member of Powell’s 1871 expedition.

Numerous river trips were undertaken in the years following Powell’s pioneering expeditions. The ill-fated Brown-Stanton voyage of 1889-90 included starts on both the Grand and the Green Rivers. (See section on “Colorado River.”) More successful were Nathan Galloway and William Richmond, trappers who left Henrys Fork, Wyo., late in 1896 and reached Needles, Calif., on February 10, 1897 (Kolb, 1927, p. 338). Trappers Charles S. Russell, E. R. Monette, and Bert Loper left Green River, Utah, in three steel boats on September 20, 1907; Russell and Monette reached Needles in one boat in February 1908, but Loper was drowned. Dellenbaugh’s 1902 book was carried by the Kolb brothers as a guide for their 1911 trip down the river (Kolb, 1927). In addition to making superb still photographs, the Kolb brothers took the first moving pictures in the canyons, and these are still being shown in the Kolb Studio on the South Rim of the Grand Canyon. Julius F. Stone and party traversed the canyons in 1909, and his account (1932) also contains excellent photographs. E. C. La Rue, of the U.S. Geological Survey, and assistants made two trips down the Green and Colorado Rivers in 1914 and 1915 and additional trips from 1921 through 1924. Their comprehensive hydrographic findings and studies, plus excellent photographs, are given in two reports (La Rue, 1916, 1925). The 1916 report also contains (p. 16-22) a good condensed account of earlier explorations and voyages from 1531 through 1911, taken in part from Dellenbaugh (1902).

As noted earlier, a modern river runners’ guide by Mutschler (1969), which logs the Green and Colorado Rivers from Green River, Utah, to Lake Powell, is now available. River mileages in this log were taken from detailed topographic maps of both rivers prepared under the direction of Herron (1917). We will visit only a few notable features of the canyons; the mile-by-mile details for the Green River can be obtained from Mutschler (1969), and those for the Colorado River, from Baars and Molenaar (1971, p. 61-99). Several other references are given below, and additional ones are given by Rabbitt (1969, p. 20-21).

All travelers down the Green River embarking from Green River, Utah, or above, were impressed with Bowknot Bend (fig. 62), so named by Powell and his men (1875, p. 54) near the beginning of Labyrinth Canyon, which they also named for its deeply entrenched meanders. The upper photograph in figure 62 was taken by Beaman on September 10, 1871, looking eastward from the west end of the narrow saddle separating the upper and lower reaches of the river; the lower photograph was taken from the same point on August 19, 1968, by Hal G. Stephens nearly 97 years later. Although there are changes in the vegetation, as described in the caption, there are virtually no visible changes in the bedrock. Nevertheless, the distant future will likely see a breakthrough, whereby Green River will shorten itself by about 7 miles (Herron, 1917, pl. 15C). It is interesting to note that the vertical cliffs of Wingate Sandstone in and west of Bowknot Bend are only a few hundred feet above the river, whereas, because of the gentle northward dip of the beds and the gentle southward grade of the rivers, the Wingate cliffs are more than 2,000 feet above the two rivers at Grand View Point and Junction Butte, at the southern tip of Island in the Sky.

At the mouth of Horseshoe Canyon, about 3 miles below Bowknot Bend, we pass a large rincon where the Green River shortened its course by about 3 miles. Some idea of the rincon’s antiquity is gained from the facts that the river is now some 350 feet lower than at cutoff time, whereas Bowknot Bend (fig. 62) has shown no visible deepening in 97 years. This rincon was not noted by Powell or other early voyagers, seemingly because they did not happen to climb the banks at this point, but it is quite noticeable on modern topographic maps and on aerial photographs. This rincon and Jackson Hole along the Colorado River may be as old as late Tertiary (fig. 80).

At a point reported to be 350 yards above the mouth of Hell Roaring Canyon, which enters from the east about 3½ miles below the rincon, an early day trapper named Julien left his mark. Stone (1932, p. 69, pl. 39A) seems to have been the first river runner to find (from a description given him by a Mr. Wheeler at Green River), record, and photograph the inscription shown in figure 63. Mutschler (1969, p. 31) indicated that this inscription is carved on a massive Moenkopi sandstone bed about 40 feet above the canyon floor. A similar inscription by Julien was found in Cataract Canyon, 31 miles below the confluence, but it is now covered by Lake Powell (Mutschler, 1969, p. 65).

Some boaters are met by car and taken out to Moab or Green River via the Horsethief Trail (fig. 1), just north of the park. The road along the river here continues south for 6½ miles to the mouths of Taylor and Upheaval Canyons, where it becomes the White Rim Trail.

Coming down the Green River, we enter Canyonlands National Park where the Grand-San Juan county line meets the Emery-Wayne county line (fig. 1), about 2¼ miles north of Taylor and Upheaval Canyons. The National Park Service had three successful test wells put down in Taylor Canyon, and water under artesian pressure was found in the White Rim Sandstone at depths of 373 to 482 feet. When funds become available, they hope to complete one or more of these wells and pump the water up to Island in the Sky, where two dry holes were drilled earlier.

About 5½ miles below Upheaval Canyon is an interesting ruin on a hill in the middle of a large nearly closed loop of the river enclosing Fort Bottom. This was noted by Dellenbaugh (1902) during Powell’s 1871 trip and was described in more detail by Mutschler (1969, p. 33-34):

The ruin consists of two, two-story, interconnected, crudely circular towers, and a third separate, completely collapsed tower, built on the summit of the bluff with a commanding view downriver and of Fort Bottom. Other collapsed structures are present on the summit, and a slab-lined cist is present beneath the Moss Back ledge west of the towers. The ruin was built of dry laid masonry and most of the mud plaster on the inside has been washed away, leaving the structure in danger of imminent collapse. Please do not climb the walls!

Fort Bottom also contains a cabin believed to have been used by Butch Cassidy and the Wild Bunch (Baker, 1971, p. 198).

At about the mouth of Millard Canyon, we leave Labyrinth Canyon and enter Stillwater Canyon, aptly named by members of the 1869 Powell voyage (Dellenbaugh, 1902, p. 276). The beginning of Stillwater Canyon is marked by vertical walls of the White Rim Sandstone. From here Powell’s men observed a butte to the southwest thought to resemble a fallen cross and named it “Butte of the Cross.” Farther downstream they realized they had been looking at two buttes, a small one in front of a larger one, so the feature was renamed “Buttes of the Cross.” An aerial view of Buttes of the Cross is shown in figure 64.

About 2 miles below the mouth of Millard Canyon, at Anderson Bottom, we reach one of the most interesting features on the river—the most recent rincon of a major river in the park, if not in the entire canyon country. Although some rincons are more recent, they are along minor tributaries such as Indian Creek (fig. 73). The cutoff at Anderson Bottom probably took place during the Pleistocene Epoch, whereas most of the others along the main rivers probably occurred during the Tertiary Period (fig. 80). An aerial view of the Anderson Bottom rincon is shown in figure 65, and a sketch of the drainage change is shown in figure 66. This feature was noted and correctly interpreted by Powell and his men, who applied the name Bonita Bend to the sharp new course the river took after the cutoff.

Continuing through Stillwater Canyon, we pass Turks Head (figs. 23, 24) and head for the confluence of the Green River with the Colorado River. Figure 67 shows the canyon just west of the confluence. The lowest and largest cliff above the river is the upper member of the Hermosa Formation, overlain by the slopes and thin ledges of the Rico Formation. The massive sandstone at the top of the canyon wall is the Cedar Mesa. Junction Butte and Grand View Point are on the right skyline.

We have already viewed the confluence and Cataract Canyon from the land and from the air (figs. 59-61); soon we will see them from the Colorado River.

Colorado River

As indicated earlier, all but one of the early river voyages began on the Green River. The Grand (Colorado) River above the confluence was neglected for some 18 years after Powell’s second voyage, until, in 1889, Frank M. Brown organized a company for construction of the proposed Denver, Colorado Canyon, and Pacific Railway. This railroad was to carry coal from mines in Colorado over a “water-level” line through the canyons of the Colorado River to the Gulf of California some 1,200 miles away; from there the coal would presumably be shipped to ports as far north as San Francisco (Dellenbaugh, 1902, p. 343-369). On March 26, 1889, Brown, president, F. C. Kendrick, chief engineer, and T. P. Rigney, assistant engineer, drove the first stake for a survey of the new line at Grand Junction, Colo., then Brown left for the East to obtain financing, and the other two plus some hired hands took off down the Grand River. After reaching the confluence they towed the boat up the Green River, thus becoming the first to make this trip upstream. They nearly ran out of food, but thanks to the hospitality of some cattlemen, they replenished their stock and after about 9 days reached the railroad at Green River, Utah. Brown, who had returned from the East, his newly appointed chief engineer, Robert Brewster Stanton, and 14 others in six ill-designed boats of cedar, rather than oak, left Green River on May 25, 1889. Against the advice of Major Powell and A. H. Thompson, Powell’s topographer on the 1871 trip, they carried no life preservers. After many mishaps, Brown and two others were drowned near the head of Marble Canyon, and the ill-fated expedition was temporarily halted. However, the indefatigable Stanton contracted for new boats built of oak and, with a reorganized party of 12, left the mouth of the Fremont (Dirty Devil) River on November 25. After many further mishaps, the party finally reached the Gulf of California on April 26, 1890. Needless to say the proposed railway was not built.

Although the Colorado River enters Canyonlands National Park about 33 river miles below Moab, most boaters or floaters begin their voyage either at Moab or near Potash, and most travelers of the White Rim Trail begin at Moab, so we will start our trip at Moab. No logs or river runners’ guides are available as yet for the reach from Moab to Potash, but below Potash some details of the geology have been described by Baars in Baars and Molenaar (1971, p. 59-87).

As noted at the beginning of this chapter, above the confluence both the Green and Colorado Rivers are very crooked, have very low grades, and are free from rapids. As with the Green, the soft rocks along the Colorado have a generally low northward dip that partly explains the river’s gentle grade and its southward flow through increasingly lower and older strata. Unlike the Green, however, the gentle dips of the strata in the canyons of the Colorado are interrupted by several gentle anticlinal (fig. 14) and synclinal (fig. 26) folds and by at least one fault. The most important of these geologic structures and other features will be noted as we journey down the river.

The first 14 miles from Moab Valley to Potash can be made either by river or by paved Utah Highway 279. This highway leaves U.S. Highway 163 near the uranium ore-reduction plant several miles northwest of Moab, leaves Moab Valley through The Portal (fig. 68), and follows the west bank of the river. A paved secondary road from Moab follows the east bank of the river through The Portal and through Kings Bottom, where it crosses the Kings Bottom syncline, to the mouth of Kane Springs Canyon, then becomes a gravel road that ascends this canyon southward to and beyond Hurrah Pass (fig. 30). High above this road north of Kings Bottom are petroglyphs and a few cliff dwellings in the vertical cliffs of Wingate Sandstone. A ranch “house” at Kings Bottom has been excavated entirely into the Wingate cliff. Convenient turnouts have been provided at several places along Highway 279 for viewing petroglyphs or other points of interest. Small viewing tubes welded to vertical steel posts having signs help visitors locate and see the features described.

The Kings Bottom syncline (fig. 30) southwest of Moab Valley brings the Navajo Sandstone down to and slightly below water level, whereas at The Portal (fig. 68) the Navajo caps the southwest wall of Moab Valley. Several anticlines at or near the river from Potash to and beyond the confluence (fig. 1) bring up strata as old as the Rico or the unnamed upper member of the Hermosa. Between these extremes, much of the river’s course lies in strata of the Cutler Formation.

About 7 miles below The Portal, Highway 279 is joined on the right by a branch line of the Denver and Rio Grand Western Railroad completed in 1962 to haul potash 36 miles from the mine at Potash north to the main line at Crescent Junction. The railroad emerges from a tunnel at the head of Bootlegger Canyon. Two natural arches near the mouth of the tunnel—Pinto and Little Rainbow Bridge—can be reached by trail. About 3 miles farther down the Colorado is a temporary dock from which jet boats and the Canyon King, a 93-foot 150-passenger stern-wheeler, take off for points downriver during the spring and early summer, when water depth permits. The Canyon King (fig. 69), a small replica of a Mississippi River stern-wheeler, carries passengers about 30 miles downriver to the foot of Dead Horse Point and returns (Lansford, 1972).

About 12 miles below The Portal we reach Potash—the potash “mine” (fig. 70) of Texas Gulf, Inc. (See fig. 31 and its associated text for description of operation.) Travelers down the jeep trail below Potash pass the evaporation ponds (fig. 71) used to separate the potash from common salt.