INTERMEDIATE STAGE OF CORDILLERAN GLACIATION 567 



glacial till. In the southeast quarter of this section 100 feet of unassorted 

 material was found, and in the northwest quarter of section 6,. township 33 

 north, range 12 west, a thickness of 150 feet was observed. Here and else- 

 where glaciated pebbles were found, though these are nowhere abundant and 

 consist mostly 'of the green, quartzitic argillite. Such striated erratics were 

 found in the sides of the valley of Arnold Creek as far out on this plain as our 

 traverse was extended." 



In October, 1912, the top of this ridge was crossed and the drift exam- 

 ined at numerous places in township 34 north, range 12 west. In the 

 east %, section 32, is an old scarp exposing the drift, but partly grassed 

 over and obscured, so that we could not determine positively that the de- 

 posit was unmodified till, though the heterogeneous mixture of fine and 

 coarse material favors such interpretation. It is possible there was an 

 error in location, and that this is the exposure seen by Mr. Thomas in 

 1911 and described above as in northwest *4, section 6, township 33 north, 

 range 12 west. At this exposure no limestone pebbles were seen and peb- 

 bles of diorite were disintegrating. Numerous striated pebbles of red and 

 green argillite were noted. Such were also found at several other ex- 

 posures (plate 14, number 8). 



The new grade on the Browning-Babb stage road, which crosses the 

 ridge in the northern part of this township, exposes 1 to 4 feet of gravelly 

 drift. This is not definitely stratified and contains striated stones, but 

 most of the pebbles are quite well rounded, as though water handled. 

 Similar drift, with striated pebbles, was found on this second plain, ex- 

 tending northeastward through the northwest part of township 11 north, 

 range 34 west, and also as far north as the northwest corner of section 16, 

 township 35 north, range 11 west. This last location is nearly 20 miles 

 from the mountain front. Striated pebbles were also found in the drift 

 on the flat top of the hill west of the Wetzel Eanch, in sections 28 and 33, 

 township 35 north, range 12 west. 



On the ridge between Peterson Coulee and Livermore Creek many 

 quartzite boulders 1 to 3 feet in diameter are to be seen where the Btage 

 road crosses. On the ridge north of Peterson Coulee (township 35 north, 

 range 12 west, sections 9 and 11) finely striated pebbles were found in the 

 gravelly drift at nearly every point where examination was made between 

 the stage road and a point 2 miles east. Some of the pebbles are nearly 

 as finely scored as those in the later drift (plate 14, number 7). No good 

 sections of the deposit were seen. 



Where slightly exposed in the north part of section 2, township 35 

 north, range 13 west, about a mile southwest of Goberta Ranch, 3 Peel o\' 

 oxidized, brownish gravelly drift was seen, containing Btriated pebbles, 



