448 



STRUCTURAL GEOLOGY OF NORTH AMERICA 



VALLE OE 

 ACATITA 



SIERRA 

 ACATITA 



ACATITA ANTICLINE 



CANON 

 BLANCO 



BLANCO ANTICLINE 



SIERRA DE LAS 

 MARGARITAS 



NORTHEAST END OF 

 VALLE DE LAS DELICIAS 



LAS DELICIAS ANTICLINE 



SIERRA 

 DEL VENADO 



AURORA LIMESTONE 

 UPPER CUCHILLO 



LOWER CUCHILLO 



WEST ^ALLUVIUM 



EAST PERMIAN? 



CROSS SECTION OF MOUNTAINS BORDERING ACATITA AND LAS DELICIAS VALLEYS NEAR NORTHERN EDGE 

 OF ACATITA.- LAS DELICIAS AREA. 



60001 



SANTA ANA 

 PARRITAS ANTICLINE 

 MUCHACHO ANTICLINE SAN ANTONIO ANTICLINE 



INDIDURA 



TERTIARY? 

 CONGL. 



PUERTO DE 

 VENTANILLAS 



ACATITA ANTICLINE 



SIERRA 

 DEL SOBACO 



SIERRA 

 CANDELARIA 



SOUTHEAST END OF SIERRA 



VALLE DE LAS DELICIAS DEL VENADO 



LAS DELICIAS ANTICLINE 



U. 2000 



SEA 

 LEVEL 



AURORA LIMESTONE 



LLUVIUM 



UPPER CUCHILLO 



WEST 



EAST 



CROSS SECTION OF MOUNTAINS BORDERING ACATITA AND LAS DELICIAS VALLEYS NEAR SOUTHERN EDGE OF ACATITA.- LAS DELICIAS AREA. ELEVATIONS 

 APPROXIMATE AND RELATIVE. 



CONCEALED (GYPSUM, 

 DOLOMITE,& LIMESTONE) 



GYPSIFEROUS BEDS 

 OF CUCHILLO 



BASAL LIMESTONE 



OF CUCHILLO 



PERMIAN 



SHALES 



LEGEND 



LIMES TONE 



Es3 



DOLOMITE 



GYPSUM 



WEST 



EAST 



PROFILE SECTION OF NORMAL FAULTING OBSERVED ON 

 SOUTH SIDE OF EAST-WEST SPUR OF SIERRA ACATITA 

 IMMEDIATELY NORTH OF LAS UVAS. LENGTH OF SECTION 

 ABOUT ONE-HALF OF ONE MILE. VERTICAL RELIEF ABOUT 

 500 FEET. 



AURORA 



LIMESTONE- 



LIMESTONE MEMBER 

 IN CUCHILLO 



WEST 



EAST 



PROFILE SECTION ON SOUTH SIDE OF EAST-WEST SPUR 

 OF SIERRA CANDELARIA ABOUT DUE NORTH OF EL RAYO. 

 LENGTH OF SECTION ABOUT THREE-QUARTERS OF ONE 

 MILE. HEIGHT OF SCARP ON EAST ABOUT 1500 FEET. 



Fig. 28.6. Cross sections of the Acotita and Las Delicias area, Coahuila, Mexico. Reproduced from Kelly, 10 36. 



PARRAS SYNCLINORIUM 



South of the Coahuila peninsula is a belt of sinuous folds that trends 

 approximately east-west. It is about 130 miles long, and tapers from a 

 width of 40 miles in the west to 20 miles in the east. The folds developed 

 out of the sediments of the Parras trough (see paleotectonic map of the 



Late Cretaceous). The anticlines plunge to the west beneath the alluvial 

 plain of the Laguna de Mayran; they are steepest on their north flank, 

 and are usually overturned. Along any one occur domes and saddles, of 

 which the domes are more overturned (de Cserna, 1956). 



At the western end of the Parras basin, the Sierra de Hispana over- 

 thrust occurs. See Fig. 28.7. The thrust sheet has ridden northeastward 



