180 QmCKSILYEli DEPOSITS OF THE PACIFIC SLOPE. 



Cliico. This will bo called tlra Wallala series. Above the Tejou is found 

 unquestionable Miocene, and resting unconformably upon the Miocene the 

 Pliocene is met with in a few localities. To the Pliocene also belong the 

 fresh-water beds of Cache Lake, wiiich will be described later in this chap- 

 ter. Between these last eras occurred an important upheaval recognized 

 by Professor AVhitney, and to which he ascribed the formation of the 

 Coast Rang-es, Avhile a great u[)lift of the Sierra and of the Basin ranges 

 he attributed, in accordance w-itli the evidence before liim, to a Post-Juras- 

 sic upheaval. 



Nomenclature here adopted. — To facilitate rcfereuco to the various groups of 

 strata Dr. White and I have agreed to give locabnames to several of the 

 California occurrences. The fossiliferous beds of the Mariposa estate will 

 be known as the Mariposa beds; the groups especially characterized by 

 the presence of Amelia in the Coast Ranges will be referred to as the 

 Knoxville series, because tliey are typically developed and have been spe- 

 cially studied in the neighborhood of the mining town of that name; the 

 rocks from whicli Messrs. Gabb and Whitney obtained a large fixuna, con- 

 sidered by them as probably equivalent to the Gault, w^ill be called the 

 Horsetown beds; and a series which occurs along the coast north of tlie' 

 Russian River will be denominated the Wallala beds. Meek's Jurassic on 

 the western slope of th3 Sierra Nevada is thus equivalent to the Mariposa 

 beds. The Shasta group of Messi-s. Gabb and Whitney is here divided 

 into two series, recognized by them as distinct, the Knoxville and tlie 

 Horsetown. The designations Chico and Tcjon are retained, but the latter 

 is considered Eocene. The Martinez is regarded as a portion of the Chico 

 series. 



Granite. — As luis been shown in the preceding chapters, there is much 

 evidence that granite underlies the entire quicksilver belt, and indeed tlie 

 whole of central California. South of San Francisco it is frequently 

 exposed in positions where erosion has been greatest, viz, along the axial 

 lines of ranges and at the sea-coast; it is also exposed at a few points 

 somewhat north of San Francisco, on the coast; and the Farallone Islands, 

 20 miles off the Golden Gate, are granite. To the north of the Bay 

 of San Francisci), away from the coast, granite is not known to occur in 



