24 MALONE JURASSIC FORMATION OF TEXAS. [bull. 26 
The region as a whole is characterized by rugged hills, ridges, an 
mountain masses rising abruptly from broad valley plains which ai 
filled to an unknown depth with coarse Tertiary ( ? ) deposits tha 
obscure the structure of the older rocks beneath them. The genera 
strike of the uplifted strata is northwest and almost all the smalle 
hills and ridges are monoclinal, with beds generally dipping south 
west. In describing the Cretaceous deposits of this region in 189] 
Mr. J. A. Tan" thought that the beds exposed north of the Sierri 
Blanca station are the oldest and that successively newer beds ar 
found to the southwest except that there is some repetition by fault 
ing. This opinion was based on the general posture and geographi 
relations of the beds and on the Iithologic similarity of certain con 
glomerate- and limestones in the Jurassic and the Cretaceous. Th- 
characteristics of the faunas involved were then practically unknown 
It will be shown, however, that the real succession of strata is verj 
different from that given in Mr. Tail's published section, the oldes 
Mesozoic rocks being found in Malone Mountain. Mr. TaflF briefs 
discussed the folding and faulting that is common throughout thll 
region and that is doubtless often present under the debris of the A T al ! 
leys as well as in the mountain masses. It would require much morn 
time and study than has yet been given to this area to work out al 
its details of structure, which is further complicated by many intra! 
she masses of igneous rock in all the larger uplifts except Malom 
Mountain. 
MALONE MOUNTAIN AND THE JURASSIC. 
The strata bearing the Jurassic fauna described by Professor (Ya- 
gin have been found only in Malone Mountain and the adjacent 
valleys. The Malone Mountain uplift extends from the Southern 
Pacific Railway near Finlay station about 5 miles in a southeasterly 
direction and ends abruptly a few hundred yards from the north- 
westerly extremity of the Quitman Mountains. Malone station, 
which is L3 miles by rail from Sierra Blanca station, is at its eastern 
base a little north of the middle. From this direction the mountain 
looks like a simple unbroken ridge, but on the southwest side it is-tj 
deeply dissected by both transverse and longitudinal valleys. 
The general structure seems to consist of a syncline along or eas 
of the crest of the principal ridge, with an anticline in the valley an 
subordinate ridges of the west slope. There are also several mind 
folds, often beautifully shown, and doubtless some faulting. Towar 
the southern end of the mountain a small anticline is developed o 
the eastern slope. Mr. TafF has published a figure of the Malo 
Mountain section h showing these general structural features. He ha 
a Second Ann. Rept. Geol. Survey Texas, pp. 714-738. h Idem, PI. XXVII. 
