o()4 B. BROWN — CRETACEOUS-EOCENE CORRELATION IN NEW MEXICO 



almost white. No massive sandstones characteristic of the Paskapoo 

 series were seen under the thick coal vein. 



At a point about II/2 miles below the Grand Tr\mk Railroad bridge 

 the river cuts through a nearly white sandy clay filled with glistening 

 particles of mica. This stratum is ^■ery homogeneous and weathers in 

 vertical faces. It continues down the river several miles, and in the val- 

 ley of Tail Creek forms the conspicuous white band near the top of the 

 formation. 



Below this conspicuous white layer the beds are as a whole lighter than 

 those above the big coal vein and are distinctly banded in light colored 

 sandy-clay strata, thin coal seams, and carbonaceous clays. 



The first dinosaur bones, a humerus and vertebrae of Trachodon sp., 

 were found at water level 1 mile above the wagon bridge across the Red 

 Deer River at the mouth of Tail Creek. This is the highest level in the 

 Edmonton beds in which dinosaur bones were found, approximately 100 

 feet below the big coal seam that marks the top of the formation. 



For several miles below this point there is little appreciable change in 

 the character of the beds ; talus and brush obscure most of the banks and 

 clean-cut escarpments are seen only in bends of the river. 



About 30 miles below Tail Creek opposite the mouth of Big Valley 

 occurs the most rugged exposure of this formation along the river. Here 

 on the west side for a distance of a mile the beds are eroded into bad 

 lands that extend a mile back from the river. The beds are composed 

 chiefly of clays, with sandstone layers toward the top,- and are distinctly 

 banded light and dark toward the top and light blue-gray at the base, 

 with an occasional thin seam of ironstone that weathers to a rust-brown 

 color. The prairie level is 470 feet above the river, and no less than 50 

 feet of the upper strata seen at Tail Creek, including the big coal seam 

 and some of the white sandstone layers, are missing. 



A generalized section taken at the lower end of the bad lands, not the 

 liighest point, shows as follows : 



Feet 



Boulder-clay 10 



T.oosely cpraented white sandstone and clay 40 



Impure lignite 1 



Light clay 10 



Lignite 3 



Clay, dark gray 20 



Lignite 1 



Sandy clay, light gray above, darker below 25 



Impure lignite and carbonaceous clay 6 



White sandy clay 20 



Brown-gray clay with ironstone 40 



