NORTH AMERICA AND THEIR VERTEBRATE FAUNA. 37 



Section 25. — In the south bank of the Wichita River, about 0.75 mile 

 southwest from the Fort Worth and Denver Railroad bridge, the bed 

 rock is exposed for a considerable distance, and extends up into the 

 bluff (Udden). The exposed section is as follows : ^^^^ 



7. Thin-bedded red sandstone of fine texture, consisting of straight, smooth, and 



persistent layers from one-eighth to one-half inch thick 4 



6. Red shale, with thin blue layers containing streaks of conglomerate, consist- 

 ing of calcareous concretions mixed with lumps of clay, both kinds averaging 

 one-fourth inch in diameter 2 



5. Red shale, containing scattered concretions of from one-third inch to 3 inches 

 in diameter; many of the largest concretions have an irregularly mammil- 

 lated surface 25 



4. Sandy brown shale i 



3. Sandstone, laminated and wavy-bedded 6 



2. Shale, brown and blue, in places consisting of lumps, as if brecciated, or as if 



it were a conglomerate of mud lumps 1.5 



1. Brown and blue shale with lentils of sand, one foot thick, extending down 



below water level in the stream 3 



Section 26. — Near the pavilion, at the north end of Wichita Lake (Udden). 

 The strata seen consist of: „ . 



Feet. 



4. Gray sandstone 2 



3. Red clay , 8 



2. Soft white sandstone 3 



I . Red clay 2 -f- 



15 + 



Section 2y. — About 4 miles south of Burkburnett the Wichita Falls and 

 Northwestern Railroad bed is cut into a low hill a mile south of the 

 main creek running east into the Red River (Udden). The west bank 

 of this cut shows some cross-bedded sandstone which lies in an old 

 channel evidently cut into the red clay by the currents which de- 

 posited the sand. It appears that the current was shifted northward, 

 as there was a greater filling-in of sand on the north side. The current 

 must have been thrown back and forth, for along one plane in the 

 main sand deposit on the north side it is clear that the sand below 

 this plane was eroded before the overlying sand was deposited. Later 

 the entire channel was filled with red clay. (See fig. 5, p. 39.) 



Section 28. — In the Red River bluflfs, on the A. A. Durfee survey, almost 

 due north from Iowa Park, outcrops of the Wichita beds are seen for 

 a distance of some 2 miles (Udden). A section was taken where the 

 bed-rock is highest, and this is as below: p^^^ 



10. Dark red sandy shale, with seams of dark red sandstone from i to 2 inches thick 8 



g. Laminated dark red sandstone 1.5 



8. Conglomerate of concretions and lumps of mud, dark red, with thin inter- 

 calated layers of sandstone 3 



7. Laminated and cross-bedded rusty red and gray sandstone 2 



6. Red clay, with a 6-inch stratum of calcareous light blue shale 10 feet above 

 its base; the red clay contains blotched gray concretions a half-foot in 



diameter 15 



5. Gray calcareous and sandy rock 1.5 



4. Red shale, in part sandy 15 



3. Calcareous sandstone, with fragments of fossils, in places with many sizes 

 and kinds of concretions; the lower side of this stratum has combs or 



narrow projecting ridges which fit in the underlying clay I 



2. Variegated shale, with calcareous concretions 6 



I. Red shale 12 



65 



The calcareous seam in No. 6 of the above section w^as noted 0.5 mile 

 farther west, in the Vjluff. 



