724 TRANS-PECOS TEXAS. 



The Arietina bed rests in contact with the porphyry of Sierra Blanca Peak 

 at the south base, and the underlying Caprotina bed is in contact with the 

 granite of Quitman Mountain at its north base, and above these beds rise in 

 their order,, first, the second Caprina bed; second, the Malone bed, repre-« 

 sented by the sands at the base of the Etholen Knobs; and third, the Etholen 

 bed, which forms the body of Etholen Knobs to the top. 



Before the prodigious erosion that has laid bare the very hearts of the 

 mountains, which now stand two thousand feet above the surface of the filled 

 up basins that surround them, the rock forming the body of Etholen bed was 

 widespread, extending from Quitman to Sierra Blanca mountains, and from 

 Malone Mountain through the pass by Etholen Knobs down the east side of 

 the Devil's Ridge to Eagle Mountain. To the east and west of Etholen Knobs 

 erosion has destroyed and the basin debris has concealed the extension of the 

 Etholen bed. 



SECTION OF WEST ETHOLEN KNOBS. 



1. Massive limestone — chert conglomeratic breccia 240 feet. 



2. Pale blue compact limestone, weathering light yellow 20 feet. 



3. Grayish dull yellow limestone .... 30 feet. 



4. Brownish yellow sandstone, with small rounded limestone pebbles 2 to 5 feet. 



5. Grayish dull yellow sandstone, with occasional worn fragments of an ob- 



long oyster two to three inches long 90 feet. 



6. Grayish dull yellow sandstone, with a thin band of fragile Exogyraf 



near the lower edge '. 10 to 15 feet. 



1. Intrusive porphyry 



8. Steel-gray sandstone, weathering dull yellowish brown, disappearing be- 

 neath basin debris 



Total 400 feet. 



The conglomerate breccia and the included rocks so beautifully represented 

 in Etholen Knobs and Malone Mountain are classed as the Etholen bed. 



These 'rocks are peculiar, appearing as they do high in the Cretaceous. 

 They are massive bowlder breccia and conglomerate, made of Carboniferous 

 limestone and chert, and having a thickness of some two hundred and forty 

 feet in one body in Etholen Knobs. 



Lithological Characters. — The rocks range from a very coarse bowlder 

 breccia, some of the fragments being as much as three feet in diameter, 

 through a well worn conglomerate to a calcareous grit. The fragments 

 forming the breccia in Malone Mountain do not appear to be in the least 

 worn, and the body of the conglomerate is formed of sub-angular fragments. 

 In places the material is composed almost entirely of limestone fragments 

 (then the prevailing pebble is chert), and in other places they are well mixed. 

 The matrix is siliceous, gritty lime, and occasionally the body of the rock is 



