CHAPTER II. 



DESCRIPTION OF THE NORTHERN PORTION OF THE PLAINS PROVINCE 

 AND THE EASTERN EDGE OF THE ROCKY MOUNTAINS. 



(See plates 2 and 3, opposite pages 64 and 66.) 



Beede^has shown that the limestone which in southern Kansas can be 

 traced into the Red Beds of Oklahoma can be followed north through Kansas 

 and even into Nebraska. Its western extension in these States is covered by- 

 Cretaceous and Tertiary deposits. Barbour'' says that the Red Beds are 

 lacking in Nebraska, though the Permian limestone appears in the eastern 

 part. This means that they do not appear on the surface and have not been 

 reported in well records. 



Darton/ in his sections across Nebraska, suggests the disappearance of 

 the Red Beds to the west by playing out, but this is only a suggestion. 



The age of the Red Beds in Dakota, Wyoming, and Colorado is still 

 uncertain. The upper portion is without doubt Triassic, but there is good 

 reason to believe that the lower parts may be Permo-Carboniferous. In the 

 following pages evidence is given in some detail to show that the Permo- 

 Carboniferous portion of these beds may be a part of the area of deposition 

 in which the vertebrate remains occur in Texas, Oklahoma, and Kansas, and 

 that the two regions are connected by red beds continuous with the western 

 edge of the limestones of the same age which can be traced through Kansas, 

 Nebraska, and eastern South Dakota. 



Knight,"^ in 1899, suggested that the so-called Permian beds of Nebraska, 

 Kansas, and Texas (including those of Oklahoma) were all connected origin- 

 ally and that they extended to the Rocky Mountains. In 1902 the same 

 writer" referred the Red Beds of the Laramie Plains to the Paleozoic on both 

 stratigraphical and paleontologic evidence and showed that the invertebrate 

 fauna resembles that of the Kansas and Nebraska beds. He says: 



"The Red Beds merge into the limestones or rest conformably upon them, and 

 here we have conditions very similar to those that have been recently discussed 

 from southern Kansas and southward. From our present knowledge it seems 

 advisable to refer the Red Beds of the Laramie Plains to the Permian." 



He further states that others have mentioned that south of the Union 

 Pacific Railroad the beds rest on the Archean and north of it conformably 

 upon the limestone. He says: 



"I have found that the limestones shade almost imperceptibly into the red 

 sandstones, and that the strata of the lower portion of the Red Beds are identical 



"Beede, Kansas University Quarterly, vol. ix, p. 191, 1900. 

 •> Barbour, Geol. Survey Nebraska, vol. i, p. 129, 1903. 



° Darton, U. S. Geological Survey, Professional Paper No. 32, plates x and xi. 

 '' Knight, Jour. Geol., vol. vii, p. 369, 1899. 

 • Knight, Jour. Geol., vol. x, p. 420, 1902. 

 62 



