90 A GEOLOGICAL SURVEY OF LANDS 



east of Chilpotin tank a dip to the east-northeast measures seven 

 degrees. 



MINOR FOLDS. 



There is a minor class of structures which are frequent in the 

 country covered by the Eagle Pass formation. These consist of 

 abrupt and small folds where the more indurated members, such 

 as the sandstones, limestones and shell breccias assume a high 

 inclination for a short distance and appear with their edges on 

 the surface of the ground as low and straight hog-backs. The 

 indurated member is sometimes unbroken and the fold is seen as a 

 well marked crest, with the rock changing its dip along the crest. 

 But at other times only one side of the fold is seen. In the latter 

 case these folds probably are to be regarded as small overthrusts. 

 These folds are due to lateral pressure. The more plastic clays 

 have yielded to this pressure by shortening in the direction the 

 pressure has been applied, while the indurated and rigid ledges 

 imbedded in the clays have been fractured and folded. The direc- 

 tion of the force was northwest and southeast, for the prevailing 

 trend of the folds are from southwest to northeast. A list of the 

 more important places where these structures were noted is as 

 below: 



1. NEJ4, survey 20, block 6. Trend N. 25° E. 



2. Near centre, survey 22, block 6. Trend N. 45° E. 



3. SEM, survey 18, block 6. Trend E NE. 



-i. South of centre, survey 98, block 6, Trend N— S. 



. 5. Yi mi. WNW of SE corner, survey 100, block 6. Trend N 68° E. 



6. NW of centre of survey 98, block 6. Trend NE— SW. 



7. Nearcentresurvey 116, block 6. Trend N. 48° E. 



ECONOMIC FEATURES. 



ARTESIAN WATER. 



Water in the Cretaceous Rocks. 



In describing the Devils river limestone reference was made 

 to the fact that there are two water-bearing horizons in this 

 limestone, one about a hundred feet below its upper surface and 

 the other some two hundred feet below this level. There is no 

 doubt that the large springs north of the Southern Pacific rail- 



