Texas Bureau of Economic Geology The Big Bend of the Rio Grande: A Guide to the Rocks, Geologic History, and Settlers of the Area of Big Bend National Park

Cover

Front Cover (1971 edition): Santa Elena Canyon of the Rio Grande
Front Cover (1987 edition): View of Casa Grande from the lower part of the South Rim trail within the Basin, Big Bend National Park (photo by Raquelle Smalley Keegan)

Introduction

The scene is set
Acknowledgments

Geologic processes

Geologic time scale
   Paleozoic era
   Mesozoic era
   Cenozoic era

Geology, place names, and legends

Marathon Basin
The Solitario
Persimmon Gap
Dog Canyon
Tornillo Flat
Hot Springs
Boquillas
Boquillas Canyon
Presidio de San Vicente
San Vicente Mountain
Mariscal Mountain
Cow Heaven anticline
Glenn Spring
The Chisos Mountains
Alsate's Face
The Watchman's House
The Basin
The South Rim Trail
Boulder Meadows
The Lost Mine Trail
The Window Trail
Burro Mesa
Castolon village
Santa Elena Canyon
Origin of the Rio Grande canyons

Natural uses of plant life

General information

Bibliography

Glossary

Index (omitted from the online edition)

Frontispiece: "Nugget." This old horse never trained for the Kentucky Derby but he did carry the writer about 73 miles between sunrise and sunset in the southern Big Bend country.

Frontispiece "Nugget," a cow horse of the Big Bend country

1. Map of West Texas showing some of the early trails and Big Bend National Park

2. The Texas Highway Department's first camp in the area that is now Big Bend National Park

3. A traveler's lonely camp in the Big Bend country

4. Big Bend National Park with principal geologic and topographic features and roads

5. Geologic time scale

6. Outline map of North America showing general location of the most persistent Paleozoic sea troughs

7, 8, 9. Fossil shellfish

10. Primitive armored fish

11. Primitive amphibian

12. Outline map of North America showing area submerged by the Mesozoic sea

13, 14. Mesozoic dinosaurs

15. Swimming reptiles

16. Flying reptiles

17. Skull of Phobosuchus riograndensis collected in Big Bend National Park

18. Agatized tree stump with roots embedded in rock; west side of Tornillo Creek, southern Tornillo Flat

19. Blocks of the earth's crust that have been broken and tilted by faults

20. Some Cenozoic mammals

21. Exhibit shelter containing some of the Mesozoic mammal bones found in the Park

22. Anticlines and synclines produced by folding of layered rocks

23. Rocks that are tilted in one direction

24. Sketch showing intrusions and extrusions in cross-section and plan views

25. Steeply tilted Paleozoic rocks about 15 miles east of Marathon, Texas

26. Diagram showing the development of folds, overturned folds, and thrust faults in horizontal rocks

27. Structure section of Marathon Basin

28. Conodonts

29. The development of laccolithic domes

30. Aerial photograph of the Solitario

31. A, Thrust faulting and overturned fold in Cretaceous rocks. B, Panoramic sketch, Persimmon Gap area

32. Asymmetric fold in Dog Canyon

33. Vertical beds of Lower Cretaceous limestone in the south wall of Dog Canyon

34. A, Sketch showing development of simple stream erosion. B, Photograph of arroyo development in horizontal rocks

35. A, Sketch showing development of step-like topography on horizontal rocks. B, Badlands development

36. The Hot Springs trading post as it appeared in 1936

37. The Boquillas Formation

38. Mail day—a group of Mexican Nationals who came to get their mail

39. Boquillas Mexico, in 1936

40. The aerial tramway which crossed the Rio Grande

41. The Sada "family" in front of their restaurant-home at Boquillas, Texas

42. The head of Boquillas Canyon as seen from the look-out stop along the Park road to the canyon

43. The Sierra del Carmen in Mexico

44. A metate, or rock mill, in the limestone ledge exposed in the river bank at the west end of the Rio Grande Village

45. A tinaja, a natural depression in the rocks

46. One of the last inhabited places at San Vicente, Texas

47. Aerial view looking southeast across the north end of Mariscal Mountain, Sierra San Vicente, and toward the Sierra del Carmen—Fronteriza escarpment south of Boquillas, Mexico

48. The head of Mariscal Canyon

49. Sketch of a graben that illustrates the structure between Mariscal and San Vicente Mountains

50. Ruins of the old Mariscal mine and part of Mariscal village as they appeared in 1963

51. Aerial photograph showing folded rock at the north end of the Cow Heaven anticline

52. Sketch showing how erosion develops valleys along the crest of an anticline

53. Elephant Tusk

54. Dominguez Mountain

55. Punta de la Sierra

56. A dike exposed in the channel of the Rio Grande

57. The Johnson ranch home and trading post in 1936

58. Aerial photograph of the Johnson ranch area in 1936 with Rio Grande, fields, and landing strip

59. Furs at the Johnson ranch trading post in 1936

60. Mortar in a boulder

61. Rock ledges elevated by the Glenn Springs intrusion

62. Dike filling of a fissure which originated from the Glenn Springs intrusion

63. Glenn Spring in 1936

64. Some abandoned adobe jacales as they appeared in 1936

65. The Glenn Springs battlefield site in 1936

66. The Glenn Springs store in 1936

67. Green Gulch, the only entrance by road to the Chisos Mountains Basin

68. A massive lava flow, about 50 feet thick, that forms the South Rim of the Chisos Mountains

69. Vernon Bailey Peak

70. Casa Grande

71. Alsate's Face

72. The Watchman's House

73. The Basin

74. The Window

75. Panoramic view of the Basin in the Chisos Mountains

76. Looking across the Basin toward Emory Peak

77. Rock jointing in the top of Emory Peak

78. The Cowboy Boot

79. The piñon-juniper forest on the higher slopes of the Chisos Mountains

80. Piñon forest in the highest Chisos Mountains

81. Looking south at the north side of Pulliam Peak

82. A small group of wild burros which are commonly seen in the lowland desert areas

83. Looking west at the Burro Mesa fault-line scarp

84. A plug-like intrusion on Burro Mesa that tilted the lava beds to form ring hogbacks around the intrusion

85. Sketches showing the development of Burro Mesa

86. Crumpled beds in the Chisos Formation that crop out between the Ward Mountain intrusion and the Burro Mesa fault

87. Canyon cut in the Chisos Formation

88. Looking northeast at Mule Ear Peaks

89. Cerro Castellan

90. A small volcanic neck near Cerro Castellan

91. Aerial view of Santa Elena Canyon

92. Sketch of Santa Elena Canyon

93. Smugglers Cave in the wall of Santa Elena Canyon

94. Sketches showing the development of drainage across a fault-block mountain

95. Willow Mountain

96. Barren surface characteristic of much of the Big Bend area

97. An abandoned ranch home near Dodson Spring

98. Mule Ear Spring

99. The candelilla wax plant in its native habitat

100. Candelilla wax being taken by pack train to the rendering vat

101. A stack of candelilla wax plant awaiting rendering

102. A small candelilla wax-rendering operation at Glenn Springs

103. An old steam boiler used as a source of heat to render candelilla wax

104. Sotol

105. Maguey or century plant

106. Spanish dagger, Spanish bayonet, soapweed, or yucca

107. Beargrass or basketgrass

108. Ocotillo

109. Ruins of the old Straw House as it appeared in 1936

110. Pitaya or strawberry cactus

111. A bee cave in Estufa Canyon about 5 miles east of the Chisos Mountains

112. Terlingua, as it appeared in 1936

113. The Chisosmine and dump in 1936

114. Freight wagon en route to Terlingua in 1936

115. The Terlingua cemetery in 1936

116. Lajitas, Texas, in 1936

117. National Park Service headquarters and administration building (omitted from the online edition)

Back Cover (1971 edition): Canyon of the Rio Grande at the "Big Hill." Santana Mesa to upper right. Road connects Big Bend National Park and Presidio, Texas.