PEALE.] GEOLOGY SECTION OF TERTIARY STRATA. 157 



Thicknees. 

 Base. Ft. lu. 



15. Space probably filled yrith soft yellowish sandstones and intei'laminated 



red and green shales and marls, a continuation upward of No. 14 170 



16. Soft, grayish-white sandstone 46 



17. Red and greenish shales _^ 23 



18. Gray sandstone 3 



19. Greenish-gray sandstone 8 3 



20. Red shales, passing up into green 3 6 



21. Yellow sandstone, covered near the top, having in all probability interlami- 



nated shales 75 



82. Yellow sandstone 48 



23. feed and greenish-gray shales, probably calcareous, especially in the red - 



layers. At the top the layers weather into rounded masses looking like 

 concretions ; the lower beds are covered with debris. The red layers are 

 from one foot to 2 feet in thickness, while the green are from 18 inches 

 to 2| feet. They are rather irregular, hovvever, the colors fading out in 

 places 45 



24. Massive, coai'se-grained yellow sandstone, with angular fracture breaking 



into large square blocks 90 



25. Greenish argillaceous and sandy shales in laminse of an inch or less thick- 



ness 22 



26. Massive vellow sandstone like that of No. 24 11 



27. Shales like those of No. 25 24 



28. White, red, and yellow sandy argillaceous and gypsiferous beds 38 4 



29. Yellow sandstone resembling that of No. 24 and No. 26, exeept that it is 



not quite so massive, and is gypsiferous 5 



30. Yellow sandstone, conglomeritic at base, then shaly, and finally massive.. 14 



31. Argillaceous and sandy shales, greenish, and in fine laminae below, becoming 



reddish above 3 



32. Massive yellow sandstone 6 



33. Micaceous sandstones and shales, with a band of massive sandstone, 20 feet 



thick, in the center. The shaly layers are fossiliferous, containing fi-ag- 



ments of bones 100 



34. Red and greenish sandstone, weathering into rounded masses 10 



35. Green and red sandstone shales with intermediate bands of sandstone 46 



36. Red and yellow mottled, rather massive, sandstone, weathering in rounded 



masses 5 



37. Hard dark-greenish sandstone ? on q 



38. Red irregular sandstone \ 



39. Soft shaly sandstones with fragments of hones 13 2 



40. Massive sandstones 9 10 



41. Shaly sandstones with fragments of iones -. 57 



42. Yellow sandstones with bones imbedded 9 



43. Yellow sandstones, somewhat shaly below but becoming more massive 



toward the top, especially in the upper five feet 34 6 



44. Argillaceous and sandy shales with fragments of bones 3 



45. Greenish and reddish sandstones, somewhat argillaceous, weathering in 



bowlder-like masses 12 



46. Massive sandstones 12 



47. Greenish sandstone, like No. 45 10 



48. Massive yellow sandstone 50 



49. Greenish and yellow shaly sandstones, with fragments of Tjones 150 



50. Massive yellow sandstones, with imbedded bones, especially abundant in 



the lower part 10 



51. Coarse, soft, gray, shaly sandstones 50 



52. Massive yellow sandstone 6 



53. Greenish-gray sandstones, mostly laminated, some of the layers having 



mud-marks on the surfaces 100 



54. Coarse yellow sandstones in massive layers \ 75 n 



55. Soft gray sandstones with numerous fragments of tones S 



56. Soft and hard gray sandstones with interlaminated shales, calcareous and • 



argillaceous, reaching from the top of layer No. 55 to the base of the 



white bluffs below station 50. The total thickness is about 1,600 



57. Alternations of dark-gray indurated clay beds, weathering white, and are- 



naceous layers reaching to the summit of station No. 50. Many of these 

 layers are probably calcareous. Gypsum does not seem to be as abun- 

 dant as in the lower layers of the section. I did not have time to make 



a detailed section. The total thickness is about 1 , 000 



Top. 



Total thickness 6,767 7 



