CALIFORNIA. 



169 



California. 



* By Dr. J. G. Cooper, late Assistant State Geologist. 



1. Volcanic and glacial, with 1. Archaean (granite) and metamorphosed rocks of uncertain age. 

 Metalliferous but not rich. Mt. Stanford, northward, Is 9,500 feet high. 



2. Glacial,and detrital ahove 16. Triassic and 17. Jurassic sandstones, containing most of the 

 gold mined on the western slopes. 



3. Detrital above 1. Archaean (granite). Surface mining. 



4. The mountains to the east produce lime, marble, copper ore and some lignite (19 c. Pliocene). 



5. Mt. Diablo, 3,876 feet high, is in full view and easily ascended from near the coal mines. 



6. Follows the 20. Quaternary (alluvial) nearly after passing through Alameda Canon 10 miles, 

 traversing 19. Tertiary, 19 c. Pliocene and 19 b. Miocene, then lignitic, with little coal. 



7. The islands visible are all like S. F. in geological structure. 



8. Eedwood Peak, 1,635 feet high, is the highest in the range opposite S. F. Mission Peak, 34 

 miles southeast, is 2.566 feet high. 



9. Mountains on the east side rise to 4,443 feet and on the west side to 3,780 feet in height. 



10. The " High Sierra," 14,000 to 15,000 feet, can be seen on clear days. The mountains east- 

 ward have the same general character as on the line from Boca to Sacramento, with the addition of 

 some 18. Cretaceous uplifts near base. 



