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GEOLOGIC GUIDEBOOK ALONG HIGHWAY 49 



[Bull. 141 



Fio. 1. Aerial view of Tuolumne Table Mountain, a lava flow which occupied a channel cut in an extensive flat surface of andesitic ash. The ash was eroded away leaving the harder 

 lava in relief as a Ions, sinuous, flat-topped ridge. Occasional remnants of the aildesite ash may be seen at the base of Table Mountain in numerous places. The Eocene bed- 

 rock surface surrounding Table Mountain was largely exhumed by this erosion. Photo by Olaf P. Jenking. 



