714 TRANS-PECOS TEXAS. 



CHAPTER V. 



THE CRETACEOUS DEPOSITS. 



BY J. A. TAFF. 



The Cretaceous strata which were studied during the present year in El 

 Paso County are embraced within an area of one hundred and eighty square 

 miles, having a width of twelve miles north and south and a length of fifteen 

 miles east and west, with a point one and one-half miles east of Sierra Blanca 

 Junction as the centre of the east side. 



The rocks of this formation appear here principally in apparently detached 

 ranges of hills rising above the general level from three hundred to seven 

 hundred feet, usually having their eastern or northeastern faces quite precipi- 

 tous, a flat top or mesa of greater or less area, and a gradual slope towards 

 the west or southwest down into the surrounding plain. The connection be- 

 tween these different exposures is generally obscured by the drift of the great 

 flats which stretch around them on every side, and adds much to the diffi- 

 culty of their study. A glance at the map accompanying this Report will, 

 give the relative positions of the localities to be described. 



Sierra Blanca is the junction of the Southern Pacific and the Texas and 

 Pacific railways, which from that point run into El Paso on the same track. 

 Six miles west of Sierra Blanca the railway passes between two mountain 

 ranges of entirely dissimilar character. The conical peaks north of the rail- 

 way are the Sierra Blanca Mountains and the rugged range on the south the 

 Quitmans. Three and one-half miles east of the Sierra Blanca Peak is the 

 Flat Mesa, with its long eastward facing scarp stretching southeast nearly to 

 Sierra Blanca Junction. East of the Quitman Mountains and south of the 

 railway are Bluff Mesa, two miles southwest of Sierra Blanca Station, and 

 Yucca Mesa, three and a half miles south of the station and to the east of the 

 pass leading from the Sierra Blanca to the Quitman Pass. The Etholen 

 Knobs are situated one-fourth and one-half mile 'respectively northwest of 

 Etholen Station, and the Malone Mountains lie west of the Quitmans and di- 

 rectly southwest of Malone Station. Partial studies were also made of the 

 Cretaceous rocks on the eastern side of the Eagle Mountains, at Finney's 

 Ranch, Carpenter's Spring, Eagle Spring, Mica Water Hole, south end of 

 the Quitman Mountains, and in the small buttes one mile northeast of Eagle 

 Flat Station. 



The following description of the rocks of this series is only intended as an 

 explanation of their stratigraphy and their correlation, as far as may be, with 

 the rocks of similar age north of the Colorado River, to which area my work 



