110 



GEOLOGICAL SUEVEY OF THE TERRITORIES. 



Fig. 27. 



the ridge toward the uorth, it is south 

 30^-35° west; aiij;le, 800-85°. Still 

 higherupit is south 1*0° west; augle,850; 

 and theu becomes, withiu a very short 

 distance, south 10° west; angle, 880-90° 

 As we i)rogress it passes the vertical 

 and dips northeast at a high angle, 



1 which gradually decreases, the dip be- 



2 coming more and more northerly until 

 the arch is completed. At the western 

 end of the caiion beneath the limestone, 

 which immediately succeeds the fossilif- 

 erous sandstone, there is a fine exposure 



4 ofquartzite-'beds, the top layers of which 



5 are somewhat calcareous. Then comes 

 G a layer of conglomerate nmde up of 



7 green and brown tlint pebbles, varying 

 from the size of a walnut to eight inches 

 in diameter. Associated with these peb- 



8 bles are geodes of quartz, some of which 

 contain calcite. 



The best section of all the beds ex- 

 posed in Spring Caiion is obtained in 

 the center of the caiion at the point 

 marked in Fig. 20 by the dotted line S. 

 We commence at the top of the hill, 

 which rises 1,100 feet above the level of 

 the creek. The first bed we notice is a 

 highly metamorphic-looking quartzite, 

 '^ which cro]>s out along the summit of 

 I'i the hill. Its general color is a dull red, 

 '"' passing in places into a dull purple and 

 j(5 again becoming light gray, with bright 

 red and yellow streaks. Some of them 

 ^^ 17 have an almost ilinty fracture. Wq esti- 

 mated the thickness of the beds at 50 

 feet. Kcxt below these beds are quartz- 

 |«o ites and light gray sandstones followed 

 by conglomerates, in the lower layers of 

 which the pebbles are very fine'. The 

 conglomerates are followed bv brown 

 limestones and sandstones, the weath- 

 ering of which gives a red tinge to the 

 soil. These beds are succeeded by fine, 

 dark-gray calcareous sandstones, which 

 break into iamiute of from two to four 

 :53 inches thickness. Next to these are the 

 coarse-grained fossil iferous sandstones 

 that I have ref'erretl to above, (layer 

 No. 7 in the section,) containing frag- 

 ments of Ostrca and C'amptonecies. They 

 might almost be called siliceous lime- 

 stones from the amount of lime they 

 contain, but they are made up of coarse 

 grain.s of sand and more properly de- 

 serve the name of sandstones. Intttr- 



