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schist on the outer shelf is basement or near basement (San 

 Onofre), then all rocks below the schist must be basement also; 

 which means that all rocks found in the deeper parts of the bay 

 should be composed of schist or at least basement rock of some 

 kind. Thus, if schist occurs on the outer shelf at the surface, 

 then only schist or basement rock should be found in the Santa 

 Monica Canyon. This is not the case since most of the rocks 

 dredged from the Santa Monica Canyon were Miocene in age. One 

 way to explain this anomalous problem is by assuming that an 

 east°west trending fault separates the rock and gravel area on 

 the outer shelf from the region north of the submarine canyon. 

 Such a fault would tilt the region north of the axis of the 

 submarine canyon downward, and uplift the outer shelf. In this 

 manner, Miocene and post-Pliocene rocks could still be present 

 in the canyon, but have been largely removed by erosion on the 

 outer shelf. Another alternative is to assume that the schist 

 dredged from the outer shelf is not in place. Third, the schist 

 and gravel area of the outer shelf may represent an eroded dome- 

 like structure. 



Poland, et_ al. (1948) mentions that the Ballona escarpment 

 along the southern boundary of the Ballona Creek has character- 

 istics which suggest faulting. For example, the escarpment is 

 more or less straight over most of its length, but more impor- 

 tant is the fact that the gravels in the old stream channel are 

 thicker on the south side. The thickening to the south can be 

 explained by tilting of the land area to the south and by 

 assuming an east-west trending fault at the southern boundary 

 of the stream channel. It is possible that the faulting and 



