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GUIDEBOOK OF THE WESTERN UNITED STATES 



large sugar refinery. 



Oil leading Port Costa the train skirts the south shore of Carquinez 

 Strait, where the steep bluffs offer many good exposures of folded 

 sedimentary rocks. The first rocks seen are Upper Cretaceous 

 (Chico) sandstone and shale. The rocks have a moderately steep 

 westward dip and trend almost directly across the course of the 

 raih'oad; so that as the train proceeds successively younger forma- 

 tions are crossed. At Eckley, a short distance beyond Port Costa, 

 brick is manufactured from the Cretaceous shale. At Crocket is a 



Mare Island, across Carquinez Strait, is the 

 site of the United States navy yard, which, however, is not readily 

 discerned from this point. The Cretaceous shales and sandstones 

 continue to Vallejo Junction and a little beyond. 



On the southeast side of San Pablo Bay, near the west end of 

 -Carquinez Strait, there are wave-cut terraces and elevated deposits 

 of marine shells of species that are still living. These terraces and 

 deposits do not show south of San Pablo Bay, and therefore seem to 

 indicate the recent elevation of a block includmg only a portion of 

 the shore around the bay* This block probably includes the Berkeley 

 Hills and a considerable territory to the east, perhaps even extendmg 

 to Suisim Bay. 



From Vallejo Junction a ferry plies to Vallejo (val-yay'ho), which 

 is on the mainland opposite the navy yard and from which railroad 



Vallejo Junction. 



Elevation 12 feet. 

 Seattle 929 miles. 



lines extend into the rich Napa and Sonoma valleys. 

 Santa Rosa, the home of the famous Luther Burbank, 

 is in the Sonoma Valley. Vallejo was named from 

 Gen. Mariano Guadalupe Vallejo, who played a 

 prominent part in the early history of California. It was the capital 

 of the State from 1851 to 1853. Beyond Vallejo Junction Carquinez 

 Strait begins to open out into San Pablo Bay.* (See PI XXIV, J?, 

 p. 78.) 



Tlie dark Cretaceous shales near the railroad station at Vallejo 

 Junction are soon succeeded by brown shales and massive sandstones 

 belonging higher in the Cretaceous system. The contact between 

 the Chico and the Martinez (Eocene) beds is in a fault zone cut by 



^ The section along the shore of San 

 Pablo Bay between VaUejo Junction and 

 Pinole (see map and section on stub of 

 sheet 13j p. 90) includes six of the most 

 widespread divisions of the eedimentary 

 series in the Coast Range region of Califor- 

 nia. The formations or groups represented 

 are the Chico (Upper Cretaceous), Martinez 

 (Eocene), Monterey (earlier Miocene), 

 San Pablo (later Miocene), Pinole tuff 

 (Pliocene), and Pleistocene. The only 

 large divisions of the middle Coast Range 

 sequence not represented are the Fran- 



ciscan (Jurassic?), Tejon (Eocene), and 

 Oligocene, all of which are found vrithin 

 a few milea to the east and south. 



In the San Pablo Bay section all the 

 formations below the Pleistocene are in- 

 luded in a syncline, on the northeastc 

 side of which the strata are nearly verti- 

 cal, but on the southeast side the dip of 

 the beds is lower. The Pleistocene beda 

 rest horizontally across the truncated 

 edges of the Miocene and Pliocene. The 

 aggregate thickness of the sediments in 

 the San Pablo Bay section is not less than 



