Vol. 6] Eeid: The Geomorphogeny of the Sierra Nevada. 119 



to faulting and shattering of the rocks. Clear Creek, however, 

 has not yet been mentioned, as it flows entirely over granodiorite. 

 There is a deep canon for several miles up this stream, which does 

 not carry a great volume of water. These is no indication that 

 the creek ever was sufficiently large to be able to cut such a large 

 canon. Nor is such a hypothesis necessary when the topography 

 is examined/ Were the canon water-cut, the two sides, being of 

 identically the same rock, and under the same conditions, should 

 be of similar form. This is not so. In the lower courses the 

 north wall is precipitous and high, while the slope of the south 

 wall is comparatively gentle. About three miles above the mouth 

 the north side is an alluvium covered flat, while the south wall 

 rises very steeply for nearly 1,600 feet. Further, the line through 

 Clear Creek if prolonged westward passes through the granite 

 fault-scarps north and southeast of Glenbrook Bay and along the 

 south boundary of the down-dropped block underlying the valley 

 at Spooners. Lastly, this rather prominent structural line marks 

 approximately the south boundary of the intensely faulted Car- 

 son topographic area. For all these reasons the course of Clear 

 Creek, with its prolongation westward, is held to be a fault-line; 

 no other hypothesis appears able to account for all the facts. 



The next structural feature of importance connected with 

 the drainage is Kings Canon. From Eagle Valley a view up 

 Kings Canon shows what appears to be a mature valley topo- 

 graphically not consonant with the other features of the geomor- 

 phy. The canon is flat-bottomed from a distance, and its course 

 is longitudinal rather than transverse. A careful examination, 

 however, reveals the true characteristic of the canon. The cross- 

 section of the valley is asymetric, the lowest part lying on the 

 east side. The east and west walls rise steeply, and the bottom 

 slopes at a low angle from the west to the east sides. The canon 

 comes rapidly to an end about three miles above its mouth, at 

 the prominent ridge extending eastward from the mass of Snow 

 Valley Peak. The other side of this ridge falls away in a very 

 steep fault-scarp, on a fault parallel to Clear Creek. The creek 

 in Kings Canon is small, and practically nothing above the 

 branch carrying the falls. It is trenching the material in the 

 canon, and there is thus exposed, not rounded stream boulders 



