The Geologic Story of Arches National Park 1

The Geologic Story of Arches National Park 1

The Geologic Story of Arches National Park

Geological Survey Bulletin 1393

 

Author: S. W. Lohman

Contents

 

 

Page

Beginning of a monument 1

Graduation to a park 5

Early history 9

Prehistoric people 9

Late arrivals 12

Geographic setting 18

Deposition of the rock materials 20

Bending and breaking of the rocks 24

Uplift and erosion of the Plateau 33

Origin and development of the arches 37

Examples of arches 46

How to see the park 50

A trip through the park 52

Colorado River canyon 52

Headquarters area 57

Courthouse Towers area 63

The Windows section 68

Delicate Arch area 74

Fiery Furnace 79

Salt Valley and Klondike Bluffs 82

Devils Garden 83

Summary of geologic history 98

Additional reading 104

Acknowledgments 105

Selected references 105

Index 109

 

 

 

 

Figures

 

 

Page

Frontispiece. Balanced Rock.

1. Arches National Park 6

2. Rock art in Arches National Park 11

3. Wolfe’s Bar-DX Ranch 14

4. Rock column of Arches National Park 21

5. Common types of rock folds 25

6. Common types of rock faults 26

7. Paradox basin 27

8. Geologic section across northwest end of Arches National Park 28

9. Index map of northwestern part of Arches National Park 28

10. Gravity anomalies over Salt Valley 31

11. Tilted block of rocks in Cache Valley graben 34

12. Jointed northeast flank of Salt Valley anticline 36

13. Index map 38

14. Tunnel Arch 43

15. “Baby Arch” 44

16. Broken Arch 45

17. Double Arch 47

18. Pothole Arch 48

19. Glen Canyon Group 53

20. Navajo Sandstone cliffs 54

21. Mouth of Salt Wash 55

22. Southeast end of faulted Cache Valley anticline 56

23. Faulted Seven Mile-Moab Valley anticline 58

24. Three Penguins 59

25. Moab Valley 60

26. Faulted wall of Entrada Sandstone 61

27. Park Avenue 62

28. Balanced rocks on south wall of Park Avenue 64

29. Courthouse Towers 65

30. The Three Gossips 66

31. Sheep Rock 66

32. Petrified sand dunes 67

33. “Hoodoos and goblins” 68

34. Eye of The Whale 69

35. Intricate crossbeds in Navajo Sandstone 70

36. Cove Arch and Cove of Caves 71

37. North Window 72

38. Looking southwestward through North Window 73

39. South Window 74

40. Turret Arch 75

41. Parade of Elephants 76

42. Suspension foot bridge across Salt Wash 78

43. Delicate Arch 78

44. Fiery Furnace 80

45. Trail to Sand Dune Arch 81

46. Sand Dune Arch 82

47. Tower Arch 84

48. Skyline Arch 85

49. Campground in Devils Garden 86

50. View north from campground 87

51. Southeastern part of Devils Garden trail 88

52. Pine Tree Arch 89

53. Landscape Arch 91

54. Navajo Arch 92

55. Partition Arch 93

56. Double O Arch 93

57. Dark Angel 94

58. “Indian-Head Arch” 95

59. Geologic time spiral 96

 

[Illustration: Petroglyph figure]

 

 

 

 

Beginning of a Monument

 

 

According to former Superintendent Bates Wilson (1956), Prof. Lawrence

M. Gould, of the University of Michigan, was the first to recognize the

geologic and scenic values of the Arches area in eastern Utah and to

urge its creation as a national monument. Mrs. Faun McConkie Tanner[1]

told me that Professor Gould, who had done a thesis problem in the

nearby La Sal Mountains, was first taken through the area by Marv

Turnbow, third owner of Wolfe cabin. (See p. 12.) When Professor Gould

went into ecstasy over the beautiful scenery, Turnbow replied, “I didn’t

know there was anything unusual about it.”

 

Dr. J. W. Williams, generally regarded as father of the monument, and L.

L. (Bish) Taylor, of the Moab Times-Independent, were the local leaders

in following up on Gould’s suggestion and, with the help of the Moab

Lions Club, their efforts finally succeeded on April 12, 1929, when

President Herbert Hoover proclaimed Arches National Monument, then

comprising only 7 square miles.[2] It was enlarged to about 53 square

miles by President Franklin D. Roosevelt’s Proclamation of November 25,

1938, and remained at nearly that size, with some boundary adjustments

on July 22, 1960, until it was enlarged to about 130 square miles by

President Lyndon B. Johnson’s Proclamation of January 20, 1969.

 

According to Breed (1947), Harry Goulding, of Monument Valley, in a

specially equipped car, traversed the rugged sand and rocks of the

Arches region in the fall of 1936 and, thus, became the first person to

drive a car into The Windows section of Arches National Monument. Soon

after, a bulldozer followed Harry’s tracks and made a passable trail.

 

When my family and I visited the monument in 1946, the entrance was

about 12 miles northwest of Moab on U.S. Highway 163 (then U.S. 160),

where Goulding’s old tire tracks led eastward past a small sign reading

“Arches National Monument 8 miles.” This primitive road crossed the

sandy, normally dry Courthouse Wash and ended in what is now called The

Windows section. At that time there was no water or ranger station, nor

were there any picnic tables or other improvements within the monument

proper, and the custodian was housed in an old barracks of the Civilian

Conservation Corps near what is now the entrance, 5 miles northwest of

Moab.

 

Former Custodian Russell L. Mahan reported (oral commun., May 1973) that

soon after our initial visit in 1946 a 500-gallon tank was installed

near Double Arch in The Windows section and connected to a drinking

fountain and that two picnic tables and a pit toilet were added. At that

time the only access to Salt Valley and what is now called Devils Garden

was a primitive dirt road which, according to Breed (1947, p. 175), left

old U.S. Highway 160 (now U.S. 163) 24 miles northwest of Moab, went 22

miles east, then followed Salt Valley Wash down to Wolfe cabin (fig. 1).

 

According to Abbey (1971), who served as a seasonal ranger beginning

about 1958, a sign had by then been erected at the crossing of

Courthouse Wash which read:

 

WARNING: QUICKSAND

DO NOT CROSS WASH

WHEN WATER IS RUNNING

 

The ranger station, his home for 6 months of the year, was what Abbey

described as “a little tin housetrailer.” Nearby was an information

display under a “lean-to shelter.” He had propane fuel for heat,

cooking, and refrigeration, and a small gasoline-engine-driven generator

for lights at night. His water came from the 500-gallon tank, which was

filled at intervals from a tank truck. At that time there were three

small dry campgrounds, each with tables, fireplaces, garbage cans, and

pit toilets. By that time an extension of the dirt road led northward to

Devils Garden, and some trails had been built and marked.

 

Bates Wilson became Custodian of the monument in 1949 and later became

Superintendent not only of Arches but also of the nearby new Canyonlands

National Park (Lohman, 1974) and the more distant Natural Bridges

National Monument. In the fall of 1969, Bates told me of some of his

early experiences in the undeveloped monument, including the evening

when 22 cars were marooned on the wrong (northeast) side of Courthouse

Wash after a flash flood. Bates and his “lone” ranger brought ropes,

coffee, and what food they could obtain in town after closing time,

threw a line across the swollen stream, had a tourist pull a rope

across, then took turns wading the stream with one hand on the rope and

the other balancing supplies on his shoulder. After a fire had been

built and hot coffee and food passed around, the spirits of the stranded

group rose considerably, except for one irate woman from the East, who

refused to budge from her car. Bates and his helper finally got the last

car out about 1 a.m., after the flood had subsided, and Mrs. Wilson then

supplied lodging and more food and coffee for those who needed it.