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University of California Publications. [Geology 



The southern portion of Little Valley begins at an east-west 

 line through the jog in the creek about a mile and a half south of 

 its canon. This line is structural, and of great importance, as 

 the map indicates. It is characterized, from west to east, by (1) 

 a sharp jog in the high west fault-scarp, the south side having 

 moved east over a quarter of a mile; (2) a rock buttress of ande- 

 site over and intruded into granite just south of the line in Little 

 Valley; (3) the fact that the flat stream terraces marking the old 

 valley floor occur south of the line above the level of the floor of 

 the middle valley; (4) distinct change of slope on the ridge 

 crests to the west and east of Little Valley ; (5) a jog in the lower 

 east slope leading down to the Washoe Valley comparable in size 

 to that in the west fault-scarp ; ( 6 ) a distinct discordance in the 

 elevations of the floor of Washoe Valley and its arm at the south- 

 west corner; and (7) the physical prolongation of the line east- 

 ward by the line of north facing cliffs that bound Washoe Valley 

 on the south. The topographic characteristics connected with 

 the high west ridge along this line are rather complex. The very 

 prominent shoulder or offset in the scarp above the jog in Frank- 

 town Creek is found to culminate in a granite knob or buttress 

 separated from the main crest by a low flat-bottomed col. Here 

 again is the occurrence of the buttress form associated with an 

 unequivocal fault. The east-west scarp which forms the north 

 face of this shoulder dips northward, and from the position of 

 the buttress at its top is probably not far different from the actual 

 fault-plane. This plane curves slightly southward to the west. 

 But this is not the only faulting apparent on the high west ridge 

 along this general line. At a point on the ridge crest a little 

 north of east from Incline, and nearly a mile north of the col 

 above mentioned, a distinct break or low place occurs. Creeks 

 flow below it east and west, in wide, shallow notches. The west 

 creek lies in a sharp break in the continuity of the slope. Just 

 west of this latter creek occurs a well-formed rock buttress jut- 

 ting out to the west, as shown on the map. 



Along this general fault line in Little Valley there are found 

 two important topographic features. First there occurs a large 

 rock buttress extending from the west scarp halfway across the 

 valley. Its east end has forced the creek to that side of the valley. 



