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GEOLOGIC GUIDEBOOK ALONG HIGHWAY 49 



[Bull. 141 



FIG. 8. Syncline in Logtown volcanics on South Fork of the Calaveras River 

 one mile south of lone. 





FIG. 10. Sharply folded anticline in Mariposa slate on Ganns Creek, 

 Mariposa County. 



** 



FIG. 9. Outcrop of "tombstone rocks" in the schistose bedrock near Campo Seco. 



FIG. 11. Stream-worn quartz boulders of ancient gold-bearing channel near the 

 Sixteen-to-One mine at Allegheny, Sierra County. Photo by Wm. 0. Jenkins. 



