584 W. T. LEE STKiTIGRAPHY OF COAL FIELDS OF XEW MEXICO 



stone, Mancos shale, which is equivalent in age to Benton, Niobrara, and 

 a part of Pierre; Mesaverde formation, Lewis shale, "Pictured Cliffs 

 sandstone," and "Laramie" formation. The "Pictured Cliffs sandstone" 

 may be regarded as the basal sandstone of the "Laramie" formation. The 

 Animas formation, lying unconformably on the "Laramie," was corre- 

 lated with the post-Laramie formations of the Denver Basin, which were 

 then generally referred to the Cretaceous, but which have recently been 

 referred to the Tertiary by G. B. Eichardson (122). 



This subdivision of the Cretaceous finds its latest expression in a sec- 

 tion measured by J. H. Gardner, a few miles east of Durango, for use in 

 a folio now in preparation. At the writer's solicitation Doctor Gardner 

 has prepared the section for use in this paper as follows : 



Section of Cretaceous Rocks measured on Florida River near Durango, Colo- 

 rado (except the Wasatch, which icas measured farther East) 



(Data furnished by J. H. Gardner) 



Feet In. Feet In. 

 Sandstone, massive ledges, coarse-grained, 



tan-colored, with thin beds of shale 80 



Sandstone alternating with beds of shale ... 70 



Sandstone, massive, tan-colored 20 



Shale, variegated and thin sandstone 100 



Sandstone, massive, coarse-grained, gray... 30 



Shale, gray and drab .' 50 



Sandstone, tan-colored, coarse-grained, with, 

 lenses of colored quartz and chert, average 



bird-egg in size 20 



Shale, variegated with lenticular beds of 



Wasatch as brown and gray sandstone 400 



determined Shale, variegated with benches of gray sand- 

 by vertebrate stone and thin ferruginous sandstone and 



remains. sandy shale 660 



(Section i Sandstone, massive, soft, gray 20 



measured on Shale, variegated 50 



east side of Sandstone, massive, coarse-grained, dark- 



Ignacio gray but locally purplish-brown 4 



Quadrangle.) Shale, variegated with brown, reddish, gray 

 and drab, with thin beds of brown and 



gray sandstone 325 



Shale, brownish and reddish, with lenses of 

 conglomeratic sandstone; pebbles of col- 

 ored quartz and ohert chiefly 85. 



Shalo. yellowish and gray 50 



Sandstone with small pebbles of quartz. ... 1 



Shale, yellowish, drab and gray 60 



Shale, tan-colored and reddish at the base, 

 containing Platan us reynoldsii Newb. ? 



at the base 250 



2,275 



