Mesozoic and Ccenozoic Geology and PalcHontolociy. 185 



its power became spent, and unable to lift the imposed strata ; a 

 similar action from the north, acting in a southerl}' direction with 

 less vigor, produced an uplift, whose action ceased between latitude 

 37° and 38°. So that while the consolidated crust of the State was up- 

 lifted at each end, it was quiescent, or nearlj^ so, in the middle ; and 

 the two forces acting against each other may have produced a rupture 

 of the superficial strata, and even a depression of the surface below the 

 sea level, in which the waters of San Pablo, Suisun, and San Francis- 

 co, have taken their resting place. 



Depressions of the strata and fissures from east to west across the 

 line of the mountain ranges are common along the Pacific, north of this 

 point, latitude 38 deg., and extend inland even east of the Sierra Ne- 

 vada. In the course of these depressions rivers run. The Klamath 

 and the Columbia are examples; which rivers might possibly never 

 have emptied their waters into the Pacific, but for this fracturing effect 

 produced b}^ opposing volcanic forces. 



The upheaval of the Coast Eanges have brought to view onlv Ter- 

 tiary strata of the Miocene, and beds of clay of the Post-pliocene 

 periods. These beds are thicker and more extensivel}' distributed in a 

 connected series than anywhere else on this continent, In this respect 

 they rival or even excel the strata on the shores of the Mediterranean. 

 It is interesting to trace the resemblance of form and outline of hills 

 produced by similarity of geological circumstances, whether of forma- 

 tion or upheaval. Manj^ of the scenes of California resemble those on 

 the shores of northern Greece, Roumelia, northern Syria and the 

 Calabrian peninsula. 



There are no phenomena in California referable, to the period of the 

 polar drift or ancient alluvium, when the transport of large blocks or 

 bowlders occurred. Over the extensive plains east of the Sierra Ne- 

 vada, in Tulare valle}', in the pleasant little oak valleys of the Coast 

 Eanges, or on the terrace plains of the shore, not a single bowlder is to 

 be met with — not a stone from which the plough might turn aside. This 

 period, was, apparently, one of quiet in this State. Yet the mountain 

 chains were elevated at this time. The topograph_y was almost the 

 same as at present, save the whole plain countr}- was below the w^ater 

 level ; there were, therefore, elevated ranges from which the counties 

 along the coast might have had scattered over their surface these 

 blocks; but the Sierra Nevada has contributed no bowlders upon these 

 plains, nor is there an}- stone included in the terraces which ma}' not 

 be classed as belonging to those ranges immediately bounding the de- 

 posit. 



