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University of California Publications. [Geology 



ing almost vertical in places. The creek that enters Kings 

 Canon a little over a mile from the mouth does so in a series of 

 three falls, aggregating over sixty feet in height, the largest be- 

 ing over twenty feet. Above the falls the creek, although it has 

 trenched quite deeply, yet flows over a comparatively gentle 

 grade. At the summit of the falls the fault fissure in the schists 

 is strikingly in evidence, and the schists themselves are in dis- 

 cordance with the normal strike and dip. Furthermore, the rock 

 exposed is perfectly fresh, a condition not found elsewhere. Both 

 structurally and physiographically this small fault-scarp is the 

 most recent in this immediate area. The question now comes 

 naturally, why do the other creeks tributary to Kings Canon not 

 show similar falls at this most recent fault line? This question 

 leads into the next important sub-topic under faulting. 



On the creek having the "falls" there is little or no discord- 

 ance in the schist on either side of the stream near the falls, and 

 hence no considerable east-west cross-faulting. The creek gul- 

 lies north of this connect with the flow of Kings Canon by 

 gradual slopes without trace of falls or rapids. But in these side 

 canons the schist walls on either side are not in accordance and 

 each creek is flowing over the trace of an east-west fault. Ash 

 Canon, to the north, is likewise a fault canon, as is evident even 

 from the geological map. Thus the large schist area east of Snow 

 Valley Peak is broken by many north-south and east-west faults. 

 The topography shown by the map expresses this; in the field 

 the topographic evidence is much stronger. The main creeks 

 flow over fault-planes. East-west movement near the falls is not 

 noticed, yet there appears to be some discordance above. And the 

 deep notch cut by the creek in the upper courses indicates a weak 

 zone which must be structural, for it is not due to differential 

 rock hardness. North of Ash Canon the granitic mass is intensely 

 fractured and faulted. The many small dikes of andesite are 

 badly dislocated. The large dike on Lakeview Hill, which is 

 mapped, shows the same character. 



Lastly, under the faulting of this topographic area comes a 

 consideration of the peculiarities of the drainage, with the faults 

 bounding them on north and south. Thus far it is evident that 

 most, if not all, the main creeks flow over lines of weakness due 



