662 



INDEX TO THE STRATIGRAPHY OF NORTH AMERICA. 



point to the south at which the Laramie shows is where it emerges from beneath the Puerco, 

 about 10^ mUes southwest of Cuba. The Laramie strata exposed between this point and 

 Raton Spring are coal bearing, the coal beds increasing in thickness and number toward the west. 



The section given by Gardner applies in a general way to the region originally 

 described by Hohnes in the valley of San Juan River and may be compared with 

 that observed by Button in the Zuni Plateau farther south. Sections by both 

 Holmes and Button are given in the latter's report.^"^'' 



South of Santa Fe, N. Mex., Lee " observed the following section. The lower 

 555 feet of the section was measured about 2 miles north of Galisteo Canyon; the 

 upper part about li miles south of Galisteo. 



Section of rocks exposed in Galisteo Canyon, south of Santa Fe, N. Mex. 



Age. 



(?) 



Upper Cre- 

 taceous. 



Jurassic or 

 Cretaceous. 



Carbonifer- 

 ous (Pton- 

 sylvanian). 



Formation. 



Galisteo 

 sandstone. 



Montana. 



Colorado. 



Dakota 

 sandstone. 



Morrison 

 formation. 



Character. 



Sandstone, conglomeratic, red, containing petrified trunks of palm wood and 

 trees of deciduous varieties. 



Sandstone and shale, coal bearing (Madrid group of Johnson) 



Sandstone with layers of black shale : 



Sandstone, brown, massive, cliff-making 



Shale, dark colored, with limestone concretions containing Benton fossils 

 near the base; calcareous layers with Niobrara fossils a little higher; and 

 limestone concretions containing Pierre fossils near the middle and at the 

 top 



Limestone in thin plates alternating with black shale (probably Green- 

 horn limestone) . 



Shale, black, with sandy layers near the base 



Sandstone, brown, in thin layers, alternating with black shale and character- 

 ized by numerous worm borings 



Sandstone, massive, buff colored, irregular texture 



Shale, black, with concretions of impure limestone that weathers yellow 



Sandstone, white, conglomeratic at the base 



Shale, blue 



Sandstone, white, friable, coarse grained, cross-bedded 



Shale and sandstone, variegated 



Sandstone and shale with beds of gypsum, red. 



Thickness 



(feet). 



460 ± 

 200 ± 

 50-100 



2,000 



20 

 110 



]5 

 10 

 70 



40 

 10 

 70 



210 



The Cretaceous of the western Great Plains near the southern boundary of 

 Colorado is described by Hills/'^''' *" from whose account the following notes are 

 derived. 



The lowest Upper Cretaceous in the Elmoro quadrangle is the Bakota sand- 

 stone, the base of which is not there exposed. On Purgatoire River, farther east, 

 it rests upon the Comanche series and, as described by Stanton,^^^^ is a gray and 

 brown, mostly massive cross-bedded sandstone about 100 feet thick. On the same 

 stream in the Elmoro quadrangle Hills measured 300 feet and estimated the total 



= Lee, W. T., unpublished notes. 



