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- 23. General geologic map and sections of Marathon uplift In pocket
- 24. Geologic map of Monument Spring and Marathon quadrangles In pocket
- 1. Index map of trans-Pecos Texas showing location of Marathon region 2
- 2. Views of the Marathon Basin from the escarpments on the east and west 9
- 3. Sections of the Cretaceous escarpments on the east and south sides of the Marathon Basin 10
- 4. Map showing deposits of gravel on the uplands east of the Marathon region 10
- 5. Block diagrams of the escarpments on the west side of the Marathon Basin 12
- 6. Block diagrams of three anticlinal mountains in the Marathon Basin, showing forms displayed during the course of their erosion 14
- 7. Block diagram of the alluvial fan of Antelope Creek, at the base of the Del Norte Mountains 17
- 8. Section across northeast part of Dagger Flat area showing the four erosion surfaces typical of the MarathonBasin 17
- 9. Maps showing possible stream history in the south half of the Marathon Basin 18
- 10. Section through Threemile Hill, showing relation of Dagger Flat sandstone to younger beds 23
- 11. Sketches showing structural features in the Marathon limestone 27
- 12. Section in bed of Alsate Creek showing sequence and structure of part of the Ordovician rocks 29
- 13. Sketches showing structural features in the Maravillas chert 37
- 14. Section across novaculite ridge at picnic grounds south of old Fort Pea Colorada 38
- 15. Thin sections of pre-Carboniferous cherts and novaculites 40
- 16. Hypothetical block diagram showing probable geography of the Marathon region in Ordovician time 44
- 17. Sketch of ripple marks in Caballos novaculite 49
- 18. Sections of lower part of Tesnus formation along Rough Creek, in southeastern part of Marathon Basin 58
- 19. Section across middle part of Devils Backbone, showing structure and relations of white quartzite beds in Tesnus formation 58
- 20. Sections between East and West Bourland Mountains, showing structural features in Tesnus formation 59
- 21. Structure section across southern part of Payne Hills 60
- 22. Sketch showing structural features of the Haymond beds in a bank of San Francisco Creek 67
- 23. Structure sections of boulder bed of Haymond formation 67
- 24. Sections showing stratigraphy and structure of the Haymond beds at the fossil-plant locality on Dugout Creek 69
- 25. Thin section of the mudstone matrix of the boulder bed 71
- 26. Plan of part of outcrop of boulder bed, showing how large limestone boulders might be interpreted as parts of a single stratum of limestone 90
- 27. Hypothetical section between exposures of boulder-bed member of Haymond formation and Hells Half Acre fault, showing possible source of boulders 91
- 28. Stratigraphic diagram of Permian rocks in the Glass Mountains 93
- 29. Map of trans-Pecos Texas showing structural features of Permian time 108
- 30. Map of trans-Pecos Texas showing progressive northeastward overlap of Comanche series 111
- 31. Restoration of structural features in the younger rocks of the Dagger Flat anticlinorium 126
- 32. Sections of Caballos novaculite in Warwick Hills, showing change in thickness of members and its relation to the Warwick overthrust 133
- 33. Diagram showing estimates of crustal shortening in different parts of the Marathon Basin 133