vaughan.] ANACACHO FOKMATION. 33 
F< el 
13. Coarsely crystalline limestone, in thick ledges, containing a species of Radio- 
lite 15 
12. Hani limestone ledge, containing small scattered calcite crystals and shell 
fragments in a brown matrix 10 
11. Coarsely crystalline yellowish-gray limestone 15 
1 0. Soft limestone 20 
9. Searp-i'< >rming limestone, several alternations of harder and softer beds about 
the base : ;< ) 
8. 1 lard limestone with small Gryphrea |() 
7. Soft limestone 20 
6. Soft limestone containing Trigonia sp 10 
5. Thick ledge of yellow limestone 10 
4. Softer, more shaly limestone 20 
3. Thick ledge of granular, argillaceous, ferruginous limestone 5 
2. Softer, rather marly material 15 
1. Ledge of limestone resembling No. 3 5 
Total thickness 320 
Base of Anacacho formation and top of the Austin chalk. 
The foregoing section must be regarded as only an approximation. 
Evidently there is considerable variation in the lithologic characters 
of the sections, frequently making it difficult to correlate from one 
section to another. The sections were, for the most part, measured 
with an aneroid barometer, and although it was attempted to check 
them by the height of the hills as given on the topographic maps, 
absolute exactness could not be expected. 
A carefully measured section along the Sabinal River was not 
obtained, but from a study from several bluffs, and from several well 
1 borings, the general characters of the equivalent beds were discovered, 
and an estimate of thickness was made. The beds here are inter- 
i mediate in character between the typically developed Anacacho forma- 
I lion and the Taylor marls. There are beds of limestone showing the 
same characters as the typical Anacacho, and also rather thick beds of 
yellow clay of the same character as the Taylor marls. There is more 
clay than in the vicinity of the Anacacho Mountains, and more lime- 
stone than in the central Texas region. These bods near Sabinal are 
considerably over 300 feet in thickness, probably 400 or more feet. 
EAGLE PASS FORMATION IN BRACKETT AND UVALDE QUADRANGLES. 
In the Uvalde quadrangle, between Turkey Creek and the Nueces 
River, the Anacacho limestone is overlain by a brown arenaceous lime- 
stone which grades into brown sandstones. 
Bull. 164 3 
