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]