Chapter I: Front Matter (1)

_The Geologic Story of_
Canyonlands
NATIONAL PARK

By S. W. Lohman
_Graphics
by John R. Stacy_

GEOLOGICAL SURVEY BULLETIN 1327

UNITED STATES DEPARTMENT OF THE INTERIOR
ROGERS C. B. MORTON, _Secretary_

GEOLOGICAL SURVEY
V. E. McKelvey, _Director_

Library of Congress catalog-card No. 74-600043

U.S. GOVERNMENT PRINTING OFFICE: 1974

For sale by the Superintendent of Documents, U.S. Government Printing
Office
Washington, D.C. 20402—Price $2.65 (paper covers)
Stock Number 2401-02498

Contents

Page
A new park is born 1
Major Powell’s river expeditions 4
Early history 9
Prehistoric people 9
Late arrivals 14
Geographic setting 17
Rocks and landforms 20
How to see the park 26
The high mesas 27
Island in the Sky 27
Dead Horse Point State Park 30
North entrance 34
Shafer and White Rim Trails 34
Grand View Point 36
Green River Overlook 43
Upheaval Dome 43
Hatch Point 46
Needles Overlook 47
Canyonlands Overlook 48
U-3 Loop 49
Anticline Overlook 50
Orange Cliffs 54
The Benchlands 58
The Maze and Land of Standing Rocks 58
The Needles district 60
Salt, Davis, and Lavender Canyons 64
The Needles and The Grabens 73
Canyons of the Green and Colorado Rivers 85
Entrenched and cutoff meanders 86
Green River 87
Colorado River 96
Summary of geologic history 112
Additional reading 117
Acknowledgments 118
Selected references 118
Index 123

Illustrations

Page
Frontispiece. Looking north from Devils Lane near Silver Stairs.
Figure
1. Map of Canyonlands National Park 6
2. Pictographs on wall of Horseshoe Canyon 10
3. The All American Man 10
4. Tower Ruin 11
5. Newspaper Rock 13
6. Cave Spring Line Camp 15
7. Canyonlands National Park and vicinity 19
8. Shallow inland sea 21
9. Rock column of Canyonlands National Park 22
10. Section across Canyonlands National Park 24
11. Aerial view of The Neck and Shafer Trail 28
12. Merrimac and Monitor Buttes 29
13. Cane Creek anticline (viewed from Dead Horse Point) 30
14. Cutaway view of anticline 31
15. Looking southwest from Dead Horse Point 32
16. Shafer Trail 35
17. Natural tanks 37
18. Canyon Viewpoint Arch 37
19. Index map showing photograph localities 38
20. The White Rim 40
21. Monument Basin from Grand View Point 41
22. Monument Basin from the air 42
23. Stillwater Canyon and Green River 44
24. Turks Head 45
25. Upheaval Dome 45
26. Cutaway view of syncline 46
27. Junction Butte and Grand View Point 48
28. Syncline in core of Lockhart Basin 49
29. View westward from U-3 loop 50
30. Looking north from Anticline Overlook 51
31. Cane Creek anticline (viewed from Anticline Overlook) 52
32. View southeastward from The Spur 55
33. Looking north down Millard Canyon 56
34. Elaterite seeping from White Rim Sandstone 59
35. White Rim Sandstone 59
36. The Doll House 60
37. Church Rock 61
38. North and south Six-Shooter Peaks 62
39. Squaw Flat Campground 64
40. Aerial view eastward across Salt Canyon 65
41. Wooden Shoe 66
42. Paul Bunyans Potty 67
43. Angel Arch 69
44. Fisheye Arch 70
45. Wedding Ring Arch 71
46. Hand Holt Arch 71
47. Cleft Arch 72
48. Arch 72
49. The Needles 73
50. Chesler Park in The Needles 73
51. The Needles and The Grabens 74
52. Trail to Druid Arch 77
53. Upper Elephant Canyon 77
54. Druid Arch 78
55. A simple graben 80
56. Cutaway view of normal fault 80
57. West wall of Cyclone Canyon Graben 81
58. Lower Elephant Canyon 81
59. The confluence from the air 82
60. The confluence from Confluence Overlook 83
61. Cataract Canyon 84
62. Bowknot Bend 89
63. Inscription by Julien 91
64. Buttes of the Cross 92
65. Anderson Bottom Rincon 94
66. Drainage changes at Anderson Bottom Rincon 94
67. Stillwater Canyon 95
68. The Portal 97
69. The _Canyon King_ 98
70. Potash mine of Texas Gulf, Inc 99
71. Evaporation ponds 99
72. Petrified log 102
73. Relatively recent rincons along Indian Creek 103
74. The Loop 104
75. Reverse fault 105
76. Cutaway view of reverse fault 105
77. Salt Creek Canyon 107
78. The Slide 107
79. Gypsum plug 109
80. Geologic time spiral 110
81. Late Cretaceous sea 114

A New Park is Born

On September 12, 1964, President Lyndon B. Johnson signed an act of Congress establishing Canyonlands as our thirty-second national park, the first addition to the park system since 1956.

The birth of Canyonlands National Park was not without labor pains. In the 1930’s virtually all the vast canyon country between Moab, Utah, and Grand Canyon, Ariz., was studied for a projected Escalante National Park. But Escalante failed to get off the ground, even when a second attempt was made in the 1950’s. Not until another proposal had been made and legislative compromises had been worked out did the park materialize, this time under a new name—Canyonlands. Among the many dignitaries who witnessed the signature on September 12 was one of the men most responsible for the park’s creation, park superintendent Bates E. Wilson, who did the pioneer spade work in the field.

The newborn park covered 400 square miles[1] at the junction of the Green and Colorado Rivers in Utah. It included such magnificent features as Island in the Sky, The Needles, Upheaval Dome, and the two great stone formations, Angel Arch and Druid Arch. On November 16, 1971, President Richard M. Nixon signed an act of Congress enlarging the park by 125 square miles in four separate parcels of land, so the area now totals 525 square miles, all in southeastern Utah, as shown on the map (fig. 1). The northern boundary was extended to include parts of Taylor and Shafer Canyons. The addition at the southeast corner takes in the headwaters of Salt and Lavender Canyons and part of Davis’ Canyon. The largest addition, at the southwest corner, includes grotesquely carved areas bearing such colorful names as The Maze, Land of Standing Rocks, The Fins, The Doll House (fig. 36), and Ernies Country (named after Ernie Larson, an early-day sheepman). The fourth parcel lies about 8 miles west of the northwest corner and encompasses much of Horseshoe Canyon, whose walls are adorned by striking pictographs (fig. 2).

At this writing (1973) the park is still in its infancy, with most of the planned developments and improvements awaiting time and money, but a good start has been made. In 1960 my family and I first traversed Island in the Sky to Grand View Point over a rough jeep trail; now it is reached with ease over a good graded road which eventually will be paved. A temporary trailer-housed entrance station near The Neck will be replaced by permanent headquarters for the Island in the Sky district after water is piped up from wells drilled near the mouth of Taylor Canyon.

In August 1965, when the Park was but 11 months old, we drove the family car over a two-track dirt “road” from Dugout Ranch to Cave Spring—temporary headquarters for the Needles district of the park, whose personnel were housed partly in trailers and partly in the cave. Now a modern paved highway, built by the State (Utah Highway 11) for 19 miles to Dugout Ranch and by San Juan County, the State of Utah, and the National Park Service for the next 18 miles, extends a total of 38 miles from U.S. Highway 163 to a new modern campground at Squaw Flat (fig. 39). The entrance station and housing for park personnel are now in trailers about 2 miles west of Cave Spring, but the trailers will be replaced by permanent structures. A shallow well near temporary headquarters supplies the only water available to the campground 1.5 miles to the west, but a new supply is to be developed for the campground and permanent headquarters. Groceries, gasoline, trailer hookups, and charter flights are available at Canyonlands Resort, just outside the eastern park boundary. The old cowboy line camp at Cave Spring has been restored so that visitors can see this phase of colorful Canyonlands history (fig. 6). Except for 2½ miles of partly graded road west from Squaw Flat, all travel to the west and south is by four-wheel-drive vehicle or on foot. In order to reach the confluence of the Green and Colorado Rivers, The Grabens, and Chesler and Virginia Parks, drivers must conquer formidable Elephant Hill, with its 40 percent grades and backup switchbacks. SOB Hill and the Silver Stairs also tax the skill and patience of jeepsters. Parts of this area will eventually be reached by graded roads, possibly by about 1977, but many hope that much of it will be kept accessible only by jeep or foot trails.

Bates Wilson, recently retired superintendent not only of Canyonlands National Park but also of nearby Arches National Park and of Natural Bridges National Monument about 80 miles to the south, is one of the few men in the park service who has guided a national park through all phases—location, promotion, establishment, and initial development. He retired in June 1972 to a ranch along the Colorado River north of Moab.

Unless credited to others, for which grateful acknowledgment is made, the color photographs were taken by me. Most of these were taken on 4- by 5-inch film in a tripod-mounted press camera using lenses of several focal lengths, but a few were taken on 35-millimeter film. Unless credited to others, the black and white photographs were kindly loaned from the Moab and Arches files of the National Park Service. The points from which most of the photographs were taken are shown in figure 19.

Major Powell’s River Expeditions

Although Major John Wesley Powell was not the first geologist to view the canyon lands, his two daring boat trips down the Green and Colorado Rivers in 1869 and 1871 made history by bringing to light the first descriptions of the geography and geology of what was then the largest remaining uncharted wilderness in the United States. Many landmarks along the canyons in the park were named by Powell and his men during those explorations. J. S. Newberry is thought to have been the first geologist to view the canyon lands—at least he seems to have been the first one whose observations were recorded (1861), but the more comprehensive findings of Powell (1875) were the ones that made history.

The 100th anniversary of Major Powell’s pioneer exploration of the Green and Colorado Rivers was commemorated in 1969 by a national centennial sponsored jointly by the U.S. Department of the Interior, the Smithsonian Institution, the National Geographic Society, and many other organizations. This touched off many magazine and newspaper articles, several commemorative programs and dedications, and several publications of lasting interest. Noteworthy among the latter is U.S. Geological Survey Professional Paper 669 entitled “The Colorado River Region and John Wesley Powell.” Of its four separate parts, two are of special interest to our Canyonlands story: part A, “John Wesley Powell: Pioneer Statesman of Federal Science,” by Rabbitt (1969) and part C, “Geologic History of the Colorado River,” by Hunt (1969). An interesting history of the National Park Service by Everhart (1972) was published as part of the national park centennial effort. The Powell Society, Ltd., of Denver, Colo., was founded mainly to publish four “River Runners’ Guides to the Canyons of the Green and Colorado Rivers, with Emphasis on Geologic Features,” covering five reaches of the two rivers from Flaming Gorge Dam, Utah, to Grand Canyon, Ariz. One of these by Mutschler (1969) covers Labyrinth, Stillwater, and Cataract Canyons, all in Canyonlands National Park. Another guidebook by Baars and Molenaar (1971) covers the Colorado River from about Potash, Utah, to the confluence with the Green, and Cataract Canyon. It is difficult to realize that thousands of people annually now boat down the canyons Powell dared to explore without knowledge of the dangers that lay ahead.

During the summer of 1968 a U.S. Geological Survey expedition led by Eugene M. Shoemaker retraced the historic 1869 and 1871 river voyages of Major Powell, in order to reoccupy the camera stations of the 1871 voyage and rephotograph the same scenes nearly 100 years later. Remarkably enough, about 150 camera stations were recovered, many requiring considerable search, and official photographer Hal G. Stephens rephotographed the scenes taken with cumbersome wet-plate cameras nearly 100 years earlier by E. O. Beaman (above the site of Lees Ferry) and by J. K. Hillers (below the site). A report containing these remarkable sets of before and after photographs hopefully will be published eventually as a delayed part of the Powell centennial. A few pairs have been published by others (Baars and Molenaar, 1971, p. 90-99), and two pairs are shown herein as figures 62 and 67. As these photographs show, in most places the rocks and even the vegetation remain virtually unchanged after nearly a century, but a few other pairs not included herein show catastrophic changes resulting from local floods or rockfalls.

On June 26, 1969, state and local officials met along the Green River at the mouth of Split Mountain Canyon, in Dinosaur National Monument, to dedicate a monument to Major Powell, commemorating the 100th anniversary of his first river trip, and to dedicate the Powell Centennial Scenic Drive, also known as the Powell Memorial Highway. In the absence of any roads closely paralleling the Green and Colorado Rivers except for short distances, this route is virtually the only means of approach to the rivers and comprises parts of several state and federal highways connecting Green River, Wyo., and Grand Canyon, Ariz. A segment of it, U.S. Highway 163, connects Crescent Junction, Moab, Monticello, and Blanding, all in Utah, and provides the principal access routes to Canyonlands and Arches National Parks and Natural Bridges National Monument.

The ceremonies at the mouth of Split Mountain Canyon began with the landing of the official party flotilla of four boats similar to the ones used 100 years earlier by Powell, who was impersonated by a bearded man dressed to resemble the one-armed major. After the dedication, the four boats resumed the voyage down the Green River for another ceremony.

On June 29 a second monument was dedicated at the head of Desolation Canyon, some 50 miles southwest of Vernal, Utah, where the 1869 Powell expedition first ventured into the then unknown wilderness. The bronze plaque identifies Desolation Canyon, named by Powell, as a national historic landmark that comprises 58,000 acres in an area 1 mile wide on each side of a 95-mile reach of the Green River.

Early History

Prehistoric people

There is abundant evidence that the canyon lands were inhabited by cliff dwellers centuries before the explorations of Powell or the earlier visits of the Spanish explorers and the fur trappers. Projectile points and other artifacts found in the nearby La Sal and Abajo Mountains indicate occupation by aborigines from about 3,000-2,000 B.C. to about 1 A.D. (Hunt, 1956).

Archeologists have found evidence of two occupations by prehistoric peoples in and near Canyonlands National Park—the Fremont people around 850 or 900 A.D. and the Pueblo or Anasazi people from about 1075 to their departure in the late 12th century (Jennings, 1970). Within the park, the most densely populated area was along Salt Canyon and its tributaries in the Needles district, but many prehistoric dwellings and granaries are also found just south of the park in Beef Basin and Ruin Park.

The Fremont people, who were mainly hunters, seemingly left no artifacts, but they did leave beautiful pictographs, or rock paintings, such as the group of ghostly human figures on the sandstone wall of Horseshoe Canyon (fig. 2), in the detached unit northwest of the park proper (fig. 1). The All American Man (fig. 3), a most unusual “Humpty Dumpty” figure painted in red, white, and blue on the wall of a cave about 3⅓ miles above the cable across the east fork of Salt Canyon, is believed to have been done in the Fremont style, but as shown in the photograph, it is next to one of three dwellings in the same cave that were built later by the Anasazi people. Tower Ruin (fig. 4) is one of many well-preserved granaries built by the Anasazi, who farmed the flood plains of creeks such as Salt and Horse Canyons. According to Jennings (1970),

There is some evidence that these early Utah people practiced a form
of irrigation, using shallow ditches to carry water to their crops.
There is also evidence that a change in climate sometime around the
late 12th century brought about summer flash flooding and induced the
cliff dwellers to abandon their Canyonlands homes and farms.

Visitors to the Needles district pass through Indian Creek State Park 12 miles west of U.S. Highway 163. The principal attraction, which is visible at the base of the Wingate Sandstone cliff on the right (north), is Newspaper Rock (fig. 5), one of the best preserved and most intriguing petroglyphs, or rock inscriptions, in the canyon lands. Many of the older cliff faces of the Wingate and Navajo Sandstones are darkened or blackened by desert varnish, a natural pigment of iron and manganese oxides. The prehistoric inhabitants of the canyon country learned that effective and enduring designs could be created simply by chiseling through the thin dark layer to reveal the buff or tan sandstone beneath. According to Jesse D. Jennings (letter of Mar. 20, 1962, to Utah Div. Parks and Recreation),

There are at least three periods of workmanship visible on the rock.
The last is quite recent since it shows men mounted on horses [brought
in by Spanish explorers]. These are probably less than 200 years old
and are probably the work of Ute tribesmen. The others cannot be
identified with any specific cultural group, although the earliest may
be as much as one thousand years old and are probably the work of the
so-called “Fremont” peoples * * *

In addition to the designs by the Fremont, Anasazi, and Ute artists, you will note a few names and dates as late as 1954.

Late arrivals

The modern history of Canyonlands is as colorful as the canyons themselves, and involves Indians, cattlemen, bank robbers, cattle rustlers, and horsethieves, followed by oil drillers, uranium hunters, potash miners, jeepsters, boaters, and tourists. A brief summary of their activities is taken mainly from a recent account by Maxine Newell (1970), to whose work you are referred for further details.

Bands of Ute and Navajo Indians roamed the canyons and mesas until the late 1800’s, but gradually they were driven out and succeeded by pioneer cattlemen, the first of whom were George and Silas Green in 1874-75, followed by the Taylor brothers in 1880-81. Cowboys named many of the natural features of the area, and the Needles country provided the scenic background for some of Zane Grey’s western tales and for David Lavender’s “One Man’s West.” Lavender Canyon, whose headwaters were recently annexed to the park, was named for him. Visitors to the Needles district pass the Dugout Ranch about 7 miles northwest of Newspaper Rock. The earliest ranch dwellings were dirt houses built by the Somerville and Scorup brothers, who bought the huge Indian Creek spread for $426,000 from the Carlisle Co. in 1918. In 1973 the ranch was operated by Robert and Heidi Redd, whose line camp at Cave Spring served as temporary park headquarters and later was restored to a typical line camp (fig. 6) as part of the Cave Spring Environmental Trail.

Robbers Roost Canyon and Spring some 30 miles west of the park was the hangout of a horsethief named Cap Brown in the seventies. From 1884 until about 1900 it was the hiding place for the notorious Butch Cassidy and his Wild Bunch, who robbed banks, trains, and mine payrolls and stole or traded horses and cattle from the ranchers. Cassidy and his gang managed to get along with the cattlemen by either replacing or paying for most of the horses and cattle, but the law finally drove them out, and Butch, the Sundance Kid, and a woman named Etta Place moved to Bolivia. According to the movie version, Butch and the Sundance Kid were hunted down and shot by Bolivian soldiers for robbing banks and mine payrolls, but according to Baker (1971) Butch returned safely to the United States and died in the Northwest in 1943 or 1944, and the Sundance Kid is reported to have died in Casper, Wyo., in 1958 at age 98. Art Ekker (Findley, 1971, fig. 3), present owner of Robbers Roost Ranch, which contains the former hangout, commented: “A lot of people are sure that Butch and his gang buried some money around Robbers Roost. Every so often somebody turns up with a map or a metal detector and wants to start digging. They’ve found a lot of rusty tin cans and old horseshoes.”

The uranium boom of the 1950’s, touched off by Charlie Steen’s fabulous Mi Vida mine south of La Sal, Utah, temporarily skyrocketed the population of Moab and sent uranium hunters into every nook and cranny of the canyon lands. Many of the jeep trails were first made then, and landing strips and prospect holes of that period are plentiful. Most of the prospects were in the Chinle Formation, particularly in the Moss Back Member at the base, but some were in rocks older than the Chinle, and some were in younger rocks. The uranium mines in the park are no longer operating, but production has been resumed in a few mines just north and east of the park. Information on some of these mines, obtained from E. P. Beroni (U.S. Atomic Energy Comm., oral commun., Feb. 14, 1973) is given at appropriate places below.

The number of boaters or floaters on the Colorado and Green Rivers is increasing steadily, and trips by jet boat and other power boats are available from Moab. Tourist travel over good roads on Island in the Sky and Hatch Point and by paved road to The Needles also is increasing steadily. Travel west of the Green River and main stem of the Colorado River is still restricted largely to a few jeep trails and to hiking or horseback riding.

Geographic Setting

Geologists have divided the United States into many provinces, each of which has distinctive geologic and topographic characteristics that set it apart from the others. One of the most intriguing and scenic of these is the Colorado Plateaus province, referred to in this report simply as the Colorado Plateau, or the Plateau. This province, which covers some 150,000 square miles and is not all plateaus, as we shall see, extends from Rifle, Colo., at the northeast to a little beyond Flagstaff, Ariz., at the southwest and from Cedar City, Utah, at the west nearly to Albuquerque, N. Mex., at the southeast. Canyonlands National Park appropriately occupies the heart of the Canyon Lands section, one of the six subdivisions of the Plateau. As the names imply, the Canyon Lands section of the Plateau comprises a high plateau, generally ranging in altitude from 5,000 to 7,000 feet, which has been intricately dissected by literally thousands of canyons.

Canyonlands National Park is drained entirely by the Colorado and Green Rivers, whose confluence is an important and scenic central feature of the park (figs. 59, 60). Individual canyons traversed or drained by these rivers are discussed in later chapters.

When Major Powell reached the confluence in 1869, the river flowing in from the northeast to join the Green River was called the Grand River, and the Green and Grand joined there to form the Colorado River. The Grand River was renamed Colorado River by act of the Colorado State Legislature approved March 24, 1921, and by act of Congress approved July 25, 1921. But the old term still remains in names such as Grand County, Colo., the headwaters region; Grand Valley, a town 16 miles west of Rifle, Colo.; Grand Valley between Palisade and Mack, Colo.; Grand Mesa, which towers more than a mile above the Grand and Gunnison River valleys; Grand Junction, Colo., a city appropriately located at the confluence of the Grand and Gunnison Rivers; Grand County, Utah, which the river traverses after entering Utah; and Grand View Point, the southern terminus of Island in the Sky.

When viewed at a distance of 1 foot, the shaded relief map (fig. 1) shows the general shape of the land surface in and near Canyonlands National Park to the same horizontal scale as it would appear to a person in a spacecraft flying at a height of 250,000 feet, or about 48 miles. This map was prepared by artist John R. Stacy from parts of the reverse sides of four plastic relief maps[2]—Salina, Moab, Cortez, and Escalante quadrangles, at a scale of 1:250,000—using a simple time- and money-saving method he devised (Stacy, 1962).

An image of Canyonlands National Park and vicinity from a satellite at a height of about 570 miles is shown in figure 7. Note white clouds and black cloud shadows on right.

Rocks and Landforms

The vivid and varied colors of the bare rocks and the fantastic canyons, buttes, spires, columns, alcoves, caves, arches, and other erosional forms of the canyon country result from a fortuitous combination of geologic and climatic circumstances and events unequaled in most other parts of the world.

First among these events was the piling up, layer upon layer, of thousands of feet of sedimentary rocks under a wide variety of environments. Sedimentary rocks of the region are composed of particles ranging in size from clay and silt through sand and gravel carried to their resting places by moving water, silt and sand particles transported by wind, and some materials precipitated from water solutions, such as limestone (calcium carbonate), dolomite (calcium and magnesium carbonate), gypsum (calcium sulfate with some water), anhydrite (calcium sulfate alone), common salt (sodium chloride), potash minerals such as potassium chloride, and a few other less common types. Some of the materials were laid down in shallow seas that once covered the area (fig. 8) or in lagoons and estuaries near the sea. Some beds were deposited by streams in inland basins or plains, a few were deposited in lakes, and some, like the Navajo Sandstone, were carried in by the wind. The character and thickness of the sedimentary rocks, and the names and ages assigned to them by geologists, are shown in the rock column in figure 9 and in the cross sections in figures 10 and 15, and the history of their deposition is discussed in the chapter “Summary of Geologic History.” The rock column was compiled mainly from generalized stratigraphic sections given by Baker (1933, 1946), McKnight (1940), Hinrichs and others (1967, 1971b), and F. A. McKeown and P. P. Orkild (U.S. Geol. Survey, unpub. data, Mar. 16, 1973).

Not exposed in the area but present far beneath the sedimentary cover, and exposed in a few surrounding places, are examples of the other two principal types of rocks: (1) igneous rocks, solidified from molten rock forced into or above younger rocks along cracks, joints, and faults and (2) much older metamorphic rocks, formed from other pre-existing rock types by great heat and pressure at extreme depths. The particles comprising the sedimentary rocks were derived by weathering and erosion of rocks of all three types in the headwater regions of the ancestral Colorado River basin. Igneous rocks of Tertiary Age (fig. 80) form the nearby La Sal, Abajo, and Henry Mountains (fig. 7).

Second among the main events leading to the formation of the canyon country was the raising and buckling of the Plateau by earth forces so that it could be vigorously attacked by various forces of erosion and so that the rock materials thus pried loose or dissolved could eventually be carted away to the Gulf of California by the ancestral Colorado River. Some idea of the enormous volume of rock thus removed is apparent when you look down some 2,000 feet to the river from any of the high overlooks, such as Dead Horse Point (fig. 15) or Green River Overlook (fig. 23), or when you lay a straightedge across the three high mesas in figure 10 and note the large volume of missing rocks below. Not so apparent, however, is the fact that some 10,000 feet of younger Mesozoic and Tertiary rocks that once overlay this high plateau also has been swept away. In all, the river has carried thousands of cubic miles of sediment to the sea and is still actively at work on this gigantic earthmoving project. In an earlier report (Lohman, 1965, p. 42) I estimated that the rate of removal may have been as great as about 3 cubic miles each century. For a few years the bulk of it was dumped into Lake Mead, but now Lake Powell is getting much of it. When these and other reservoirs ultimately become filled with sediment, for reservoirs and lakes are but temporary things, the Gulf of California will again become the burial ground.

AGE (millions of yrs ago)
GEOLOGIC AGE
NAME OF ROCK FORMATION
KIND OF ROCK AND HOW IT IS SCULPTURED BY EROSION
THICKNESS (feet)
NAMED FOR OCCURRENCE AT OR NEAR

150
Jurassic
Entrada Sandstone
Crossbedded white fine-grained sandstone at top (Moab
Member); salmon colored to pink, fine-grained,
generally crossbedded sandstone in middle (Slick Rock
Member); red earthy sandstone and siltstone at base
(Dewey Bridge Member, grades into Carmel Formation
west of Green River). Forms steep-sided buttes north,
east, and west of park.
400-500
Entrada Point, San Rafael Swell, Utah
175
Jurassic & Triassic(?)
Glen Can Group
Navajo Sandstone
Crossbedded buff to gray sandstone, some red sandstone, and
thin beds of limestone. Residual rounded patches on
highest mesas.
325-550
Navajo Country, Ariz., New Mexico, Utah
Late Triassic(?)
Kayenta Formation
Irregularly bedded stream-laid gray, buff, lavender and red
fine-to-coarse-grained sandstone and siltstone. Caps
most high mesas and forms tops of highest cliffs.
Contains fresh-water fossils.
160-300
Glen Canyon, S. Utah, Kayenta, Arizona
200
Late Triassic
Wingate Sandstone
Buff and light red generally crossbedded medium-grained
sandstone. Forms highest cliffs, many of which are
coated with black desert varnish.
210-340
Ft. Wingate, New Mexico
Chinle Fm.
Unnamed upper member
Reddish siltstone, mudstone, and sandstone locally bleached
to bluish or greenish gray, and few thin beds of
limestone. Forms steep slopes at base of highest
cliffs. Contains some fossil wood and reptile bones.
205-740
Chinle Valley, Ariz.
Moss Back Mbr
Gray, brown, and gray-green sandstone and conglomerate.
0-80
Moss Back Ridge, Utah
215
Middle(?) and Early Triassic
Moenkopi Fm.
Unnamed upper member
Brick red, reddish-brown, and brown mudstone and sandstone,
and some conglomerate and gypsum. Forms slopes broken
by thin ledges.
250-940
Moenkopi Wash, Ariz.
Triassic(?)
Hoskinnini Tongue
Pale-brown fine-to-coarse-grained sandstone; forms ledges.
0-120
Hoskinnini Mesa, Ariz.
250
Permian
Cutler Fm.
Undivided Cutler Formation in northeastern part of area is
composed of buff, red, and purple arkosic sandstone
and conglomerate. South of Indian Creek is the thick
Cedar Mesa Sandstone Member, composed of massive
mainly crossbedded white to pale red sandstone with
thin beds of cherty limestone. Forms needles, arches
and other erosional features. Thickening southwestward
is the White Rim Sandstone Member of white crossbedded
sandstone.
800-1,000
Cutler Creek, Colo.
White Rim Sandstone Member
White Rim, Wayne Co., Utah
Organ Rock Tongue
Organ Rock, Utah
Cedar Mesa Sandstone Member
Cedar Mesa, S. E. Utah
Rico Formation
Buff, red, and purple arkosic sandstone and conglomerate
containing several thin beds of marine fossiliferous
limestone. Forms moderately steep slopes.
250-585
Rico, Colo.
300
Pennsylvanian
Hermosa Formation
Hermosa Creek, Animas River Valley, Colo.
Unnamed upper member
Blue, greenish, and gray fossiliferous limestone interbedded
with white, gray, and greenish sandstone and gray to
green shale. Lower part known only from deep wells.
Forms steep canyon walls.
900-1,800
Paradox Member
Salt, gypsum, and anhydrite with interbedded black and brown
shale; some limestone.
?
Paradox Valley, Colo.

Last but far from least among the factors responsible for the grandeur of the canyon country is the desert climate, which allows us to see virtually every foot of the vividly colored naked rocks and has made possible the creation and preservation of such a wide variety of fantastic sculptures. A wetter climate would have produced a far different and smoother landscape in which most of the rocks and land forms would have been hidden by vegetation. In the canyon lands the vegetation is mainly on the high mesas and on the narrow flood plains bordering the rivers, but scanty vegetation does grow on the gentle slopes or flats.

The desert climate has combined with the nearly flat lying layers of sediments of different character, hardness, and thickness to produce steep slopes having many cliffs and ledges and generally sharp to angular edges rather than the subdued rounded forms of more humid regions. This has led geologists to refer to such terrain as having “layer-cake geology,” and this is brought out by the profile in the rock column (fig. 9), by the cross section (fig. 10), by figure 15, and by many of the other photographs. But the baker of this cake was rather careless—not only do the layers range widely in thickness and character, but some are wedge shaped, thick on one side of the cake but thin or absent on the other. Then too, when he ran out of icing in the midst of a layer, he was apt to finish with a different kind or color, for no inspector was on the job to insure orderly construction.

If all the rock strata in the park were present at one locality, their sequence and thickness would be those shown on the right-hand side of the graphic section in figure 9. However, because of the lateral changes in thickness and character and the wedging out of certain beds, such as the White Rim Sandstone Member of the Cutler Formation, no two sections of the strata are exactly alike. This will be brought out in photographs of different exposures of rocks in various parts of the park.

An often-asked question is, why are most of the rocks so red? This can be answered by one word—iron, the same pigment used in rouge and in paint for barns and boxcars. Various oxides of iron, some including water, produce not only brick red but also pink, salmon, brown, buff, yellow, and even green or bluish green. This does not imply that the rocks could be considered as sources of iron ore, for the merest trace of iron, generally only 1 to 3 percent, is enough to produce even the darkest shades of red. The only rocks in the park that contain virtually no iron are white sandstones of the White Rim Sandstone Member of the Cutler Formation (figs. 21-24) and the Navajo Sandstone.

As pointed out by Stokes (1970, p. 3), microscopic examination of the colored grains of quartz or other minerals shows the pigment to be merely a thin coating on and between white or colorless particles. Sand or silt weathered from such rocks soon loses its color by the scouring action of wind or water, so most of the sand dunes and sand bars are white or nearly so.

The map (fig. 1) and cross section (fig. 10) of the park show that in general the major features of the landscape lie at three different and distinctive levels. A recently erected plaque on Grand View Point appropriately refers to these levels as the “Three Worlds.” The high plateaus, or mesas, in and adjoining the park dominate the skyline—in fact, the central one, between the Green and Colorado Rivers, is appropriately named Island in the Sky. If you stand on either the east or the west shore of this towering cliff-bordered island, you can look across a sea of fantastic erosional forms to a similar cliff-bordered shore at about the same level. Closer inspection of the sea of rocks on either side shows relatively flat benches or platforms about halfway to the bottom; below these are the generally steep sided or cliff-bordered canyons of the two rivers and their larger tributaries. From some vantage points along the shore, such as Dead Horse Point (fig. 15) or Green River Overlook (fig. 23), you can see the deepest level of all—the channels and flood plains of the Green and Colorado Rivers.

What caused the “Three Worlds” and the formidable cliffs supporting the high mesas or forming towering monoliths like Angel Arch or Druid Arch (figs. 43, 54)? Differences in the composition, hardness, arrangement, and thickness of the rock layers determine their ability to withstand the forces of fracturing and erosion and hence their tendency to form cliffs, ledges, or slopes. Most of the cliff- or ledge-forming rocks are sandstones consisting of sand grains deposited by wind or water and later cemented together by silica (SiO₂), calcium carbonate (CaCO₃), or one of the iron oxides (such as Fe₂O₃), but some hard, resistant ledges are made of limestone (calcium carbonate). The rock column (fig. 9) shows in general how these rock formations are sculptured by erosion and how they protect underlying layers from more rapid erosion. The nearly vertical cliffs supporting the highest mesas consist of the well-cemented Wingate Sandstone protected above by the even harder sandstone of the Kayenta Formation. To borrow from an earlier report of mine (Lohman, 1965, p. 17),

Vertical cliffs and shafts of the Wingate Sandstone endure only where
the top of the formation is capped by beds of the next younger rock
unit—the Kayenta Formation. The Kayenta is much more resistant than
the Wingate, so even a few feet of the Kayenta * * * protect the rock
beneath.

In some places remnants of the overlying Navajo Sandstone make up the topmost unit of the cliff.

How to See the Park

The question of how to see the park has no simple answer, for the park is too vast and complex to comprehend by a quick visit to any one of its many and varied parts or by any one means of transportation. Some, as did Major Powell, view it only from the rivers—by boat plus a few back-breaking climbs up the bordering canyon walls. Others see only the small parts reachable by passenger cars. The more venturesome see vastly more by jeep, foot, or horseback. And a few prefer to view it as the birds do—from the air. Many, those who put aside their magazines long enough, get bird’s-eye views without half trying, for Canyonlands is beneath the principal air routes connecting Los Angeles with Grand Junction and Denver. Actually, a full appreciation of all the wonders and beauties of the park is possible only by combining all these approaches and methods of locomotion, but only a few fortunate souls such as Bates Wilson have thus been able to inspect virtually every square foot of it.

The task clearly before me, then, is how best to present such a complex wonderland to you, the reader. The method I selected, after considerable thought and a few false starts, is to begin at the top—the high mesas—and work my way downward much as the rivers have done in carving out this fantastic area, to some of the broad benchlands beneath the mesas and eventually to the river channels and deep canyons. Although the approach I selected may not be the best, and admittedly is but one of several that comes to mind, I hope it gets the job done.

The High Mesas

Even though the “peninsular” mesas east and west of Island in the Sky, known respectively as Hatch Point and the Orange Cliffs, lie outside the present boundaries, they provide breathtaking views of important features within the park, so brief descriptions of them are included below. But first, let us take a closer look at Island in the Sky.

Island in the Sky

As the map (fig. 1) shows, Island in the Sky is really a fork of a wedge-shaped peninsula extending southward between the two rivers. An outlier to the south named Junction Butte has already been severed from the main peninsula by erosion and now is a true island. (See frontispiece and fig. 22.) A large chunk of Island in the Sky south of The Neck was about to be severed by erosion from the main peninsula to become a true island, when recent widening and grading of the road gave it a temporary reprieve. When my family and I first squeaked over this narrow neck in 1960 by jeep, furtive glances to right or left showed the two canyons perilously close, and complete severance seemed imminent. The road builders have staved off disaster for a few thousand years, but ultimately the large section to the south will become another island, and a bridge will be required to connect it to the mainland. Its appearance from the air before the road widening is shown in figure 11.

The entrance road to Island in the Sky intersects U.S. Highway 163 at a point 10 miles northwest of Moab, or 21 miles southeast of Crescent Junction on Interstate Highway 70. From U.S. 163 a paved road climbs colorful Sevenmile Canyon past sandstone cliffs of the Wingate, Kayenta, and Navajo Formations to reach the high mesa. There, just “offshore” to the north, are anchored the “battleships” that guard the island—Merrimac and Monitor Buttes (fig. 12). These landmarks are composed of the Entrada Sandstone—the same rock that forms Church Rock at the entrance to the Needles district (fig. 37) and that shapes the spectacular arches in Arches National Park. All three members of the Entrada (Wright and others, 1962), as noted in the figure 12 caption, are present here as well as at Church Rock. Eleven miles from the junction with U.S. Highway 163 a graded road to the right, called Horsethief Trail, goes 16 miles down to the Green River, where it connects with roads following the river both upstream and downstream. The road upstream leads to two uranium mines in the lower part of Mineral Canyon which were reactivated in 1972 and 1973. The switchbacks are quite spectacular and are reminiscent of the Shafer Trail. Three miles south of the Horsethief Trail turnoff is a fork in the road—to the left the pavement continues to Dead Horse Point, and straight ahead a graded road leads southward to the Island in the Sky district of Canyonlands National Park.

Most of Island in the Sky has a scattered growth of piñon and juniper trees, but several large flat areas, such as Grays Pasture, contain sufficient sandy soil to support a mantle of grass and weeds, which is used for grazing; however, grazing in this part of the park will be discontinued in 1975.

DEAD HORSE POINT STATE PARK

Let us follow the paved road from U.S. Highway 163 all the way to Dead Horse Point, which was set aside as a state park in 1957. The park has a visitor center, museum, modern campgrounds and picnic facilities, and piped water, which is hauled all the way from Moab. An entrance fee of $1 permits us to drive across the narrow neck to a parking area near the point proper, which is protected by stone walls and is provided with a ramada, benches, paths, and sanitary facilities. From Dead Horse Point we get breathtaking views in several directions, including a loop of the Colorado River called the Goose Neck, 2,000 feet nearly straight down.

How did such a magnificent viewpoint get such a macabre name? Dead Horse Point was named for a sad but colorful legend concerning a band of wild horses that once roamed the high mesas. The point is really an embryo island separated from the mainland by a narrow neck barely wide enough for the present road. In the early cowboy days the island was used as a natural corral in which wild mustangs were penned up behind a short fence across the neck so that the better ones could be sorted out and driven to mines in the San Juan Mountains of Colorado. A band of horses corralled too long without water allegedly died of thirst within sight of the river 2,000 feet below, hence the name of the point, or at least so one version of the story goes. Some versions allude to the wranglers as cowboys; others, as horsethieves.

To the northeast we can see the Cane Creek anticline—an upward fold of the rocks—behind which loom the La Sal Mountains (fig. 13). A cutaway view of a typical anticline is shown in figure 14. A better view of the Cane Creek anticline can be seen from Anticline Overlook, as shown in figure 31. From our vantage point at Dead Horse Point, we can see much of Hatch Point, including Anticline Overlook, by looking east and southeast. Spectacular views of the northern part of Canyonlands National Park lie to the south, southwest, and east. Looking southwest (fig. 15), we see most of the rock formations exposed in Canyonlands—more than can be seen from any other vantage point in or near the park. The names of the visible rock units shown in figure 15 can be compared with the complete list in the rock column (fig. 9). Parts of Shafer dome, a “closed” rounded anticline, are visible in the lower left of figure 15 and in the lower right of figure 13. Its general domelike shape is outlined by the bluish-white Shafer limestone, a marker bed which also caps the bench on the peninsula within the Goose Neck of the river. This limestone, which here forms the top of the Rico Formation, is not shown in the rock column (fig. 9) because its exposure is limited to the Shafer dome and the Cane Creek anticline and its name is used only locally by prospectors for oil and gas.

Note that the White Rim Sandstone Member of the Cutler Formation, referred to hereinafter simply as the White Rim Sandstone, becomes thinner toward the right (northeast) in figure 15 but is absent entirely in figure 13, just a short distance to the northeast. The gradual disappearance of recognizable beds of this type toward the northeast, including the disappearance of some limestone beds containing marine fossils, are examples of what geologists call facies changes. Here the changes result from the fact that while strata were being deposited in or near ancient seas that lay to the southwest, beds of different character were being laid down on land by streams emanating from the northeast. This will be gone into in more detail in discussions that accompany illustrations to follow, particularly figure 27, fig. 31, and fig. 35.

NORTH ENTRANCE

The north entrance to the Island in the Sky district of Canyonlands National Park used to be 6 miles south of the junction with the paved road to Dead Horse Point, but since the land additions of November 1971, it is only 4½ miles south of this junction. A temporary trailer-housed entrance station marks the old boundary.

SHAFER AND WHITE RIM TRAILS

During the early 1950’s a remarkable but hair-raising road known as Shafer Trail was cut down the face of the cliffs below The Neck to reach the C Group of uranium claims near the head of Lathrop Canyon. It branches southward from the park road a mile south of the new entrance, then descends in a series of switchbacks. The aerial view (fig. 11) shows the upper trail and The Neck before the park road was graded and widened, and a view from near The Neck (fig. 16) shows the precipitous cliffs the trail descends. It follows the general route of an old foot trail.

Shafer Trail connects with the White Rim Trail, which, as the name suggests, is built mainly on the White Rim, after which the White Rim Sandstone was named. The White Rim Trail can be followed northeastward to join the pavement at Potash, or it can be followed southward along the Colorado River canyons to Junction Butte, thence northward along Stillwater and Labyrinth Canyons of the Green River to and beyond the northern boundary of the park. At Horsethief Bottom, you can leave the canyon by Horsethief Trail and rejoin the paved road leading northward to U.S. 163. At Lathrop Canyon, 8 or 10 miles south of where Shafer Trail meets the White Rim Trail, a branch of the White Rim Trail leads downward to the Colorado River, where picnic tables and sanitary facilities are provided. This is used as a lunch stop by some boating groups.

Although some two-wheel-drive cars or trucks have traversed the White Rim and Shafer Trails, they may encounter trouble with deep sand, washouts, or fallen rocks, so four-wheel-drive vehicles are recommended. In the summer these trails should not be attempted without plenty of water, and two vehicles traveling together provide an added margin of safety. All vehicles should carry emergency equipment including a shovel, tow chain or rope, jack, tire tools, and other necessary items. Geologists and uranium prospectors working along the White Rim Trail have obtained good drinking water from small springs that flow from the base of the White Rim Sandstone in many places (Neal Hinrichs, U.S. Geol. Survey, oral commun., Feb. 1973). After rains, runoff gathers in large potholes in the White Rim Sandstone in some places and affords emergency drinking water. Several such potholes filled with water are shown in figure 17. Some potholes occur also in the Cedar Mesa Sandstone in the Needles district.

GRAND VIEW POINT

About a mile southwest of The Neck, the road crosses Grays Pasture—the widest and flattest part of Island in the Sky. The drive over this flat grassland yields not the slightest hint of the awesome cliff-walled chasms on either side of the island. Some 5 miles southwest of The Neck, both the island and the road branch like a Y. At a point 0.4 mile north of the Y, Mesa Trail leads one-quarter mile east to Canyon Viewpoint Arch, which frames the Colorado River canyon and the La Sal Mountains (fig. 18). This arch, at the very top edge of the cliff, is composed of the lower part of the Navajo Sandstone. The only other arch of Navajo Sandstone in or near the park that I know of is the small one shown in figure 33, but of course there may be others.

Let us now take the branch south of the Y and follow the narrow crest of Grand View Point for about 6 miles to the main overlook. About 0.9 mile south of the Y, a short walk to the west over the lower part of the Navajo Sandstone affords a magnificent view of Stillwater Canyon of the Green River, including Turks Head (fig. 23, fig. 24). Half way to the point is a parking area and overlook, from which we get a spectacular view of canyons cutting the White Rim and of the La Sal Mountains beyond (fig. 20). Note that the White Rim Sandstone, which forms the broad bench appropriately named the White Rim, is here much thicker than where seen near Dead Horse Point (fig. 15).

Three more miles southward takes us to Grand View Point and its nearby picnic area. Though named after the former Grand River some 2,000 feet below, Grand View Point has a double meaning, for we see from here a truly grand view (fig. 21)! At our feet is spectacular Monument Basin, cut below the White Rim into the brick-red Organ Rock Tongue of the Cutler Formation. The White Rim Sandstone here is slightly thicker than to the northeast (fig. 20) but thinner than to the west (fig. 23), because it forms a wedge-shaped body that thickens westward. In the distance southeastward are the Abajo Mountains, just west of Monticello, Utah. The prominent projection on Hatch Point on the left skyline is Needles Overlook, from which the photograph in figure 27 was taken. A closeup view of Monument Basin, showing Junction Butte and Grand View Point in the background, is shown in figure 22. The slender spire in the foreground has a measured height of 305 feet (Findley, 1971, p. 78).

GREEN RIVER OVERLOOK

About a quarter mile west of the Y, a left fork of the road goes about a mile and a half to Green River Overlook, which provides a superb view of Stillwater Canyon of the Green River, the Orange Cliffs beyond, and the Henry Mountains in the extreme distance (fig. 23). Note that here the White Rim Sandstone is much thicker than in preceding views. The prominent butte enclosed by the loop of the river is known as Turks Head and is better seen from the air (fig. 24). The light-colored band near the base of the cliffs in the background of figure 24 is characteristic of the bleached upper part of the Moenkopi Formation in this part of the park. According to F. A. McKeown and P. P. Orkild (U.S. Geol. Survey, unpub. data, Feb. 16, 1973), petroliferous material or odor generally occurs in this bleached zone and in the basal beds of the Moenkopi.

The campground just north of Green River Overlook has no water at this writing (1973), but water from wells in Taylor Canyon will eventually be piped to nearby parts of Island in the Sky.

UPHEAVAL DOME