VARIOUS LOCALITIES OF THE ASPHALTE GROUP. 
63 
I am inclined to look upon this series as the most recently elevated strata in California ; the 
upper soft rock, which is the most persistent and easiest recognized, being the distinguishing 
stratum. I have not observed them north of San Luis hay, not having reached the coast north 
of that point. It is likely they extend along shore to Punto Gordo; the deeply excavated 
beach would imply some such soft rocks at the base of the Santa Lucia range. Prom San 
Luis, south, they may he traced, by hfaporna, along shore, and occupying the low hills of the 
Saint Inez range, at Point Concepcion ; thence under the terrace at Gaviote pass, and along 
shore, close to Santa Barbara, where it rises up to form a terrace cliff harrier 100 feet high. 
From Santa Barbara it may he traced, not far from the shore, to San Buenaventura; and 
east of the Santa Clara river it leaves the shore, running directly east, and forming the upper 
beds of the low hills called the Sierra Monica, whence they may he found running out north of 
the town of Los Angeles. 
In the Santa Margarita valley these strata were not observed occupying a prominent posi¬ 
tion—perhaps the centre of the plain may he occupied by them—hut they were found in the 
northern end of the Santa Maria valley, where they form the latest beds of the San Jose moun¬ 
tains on both slopes, and are found occupying a position superior to the ostrea and pecten 
beds, corresponding to those described in the account of Santa Margarita valley. In the valley 
of Santa Maria river they were found traversing the base of the hills about 150 to 300 feet 
above the level of the valley; upon these layers the lowest hill terrace of the valley was placed, 
the strata extended twenty miles along the hills towards the head-waters of the river. This 
is the furthest point inland at which they were observed, about sixty miles from the sea. In 
their extended course (above 200 miles from north to south) they have a varied dip along the 
San Jose range, whose axis is granite ; they are unaltered in character, and have an elevation 
on the east side not more than 15°, while on the west it approaches 45°. 
In the valley of San Luis the dip is 20°, while along the coast at Gaviote pass it is 40° 
Both in Santa Barbara and Los Angeles counties it varies from 8° to verticality, in proportion 
to its proximity to the trappean and trachyte eruptions. In the eastern end of the Sierra 
Monica, north of Los Angeles, the strata are almost vertical. 
Though not observed further north on this survey than Estero hay, there is no reason to 
doubt of their occurrence in the valleys of the Coast Bange further inland. From Dr. Trask’s 
description, I am inclined to think that beds found by him near the mouth of the Pajaro river, 
and those observed by Mr. W. P. Blake, near the town of Monterey, are extensions of those to 
the north. Dr. Trask notices that these beds, the two upper series of the group described 
here, are never found at a lofty elevation—that they are not found above an altitude of 500 
feet. This was also observed upon this survey, with one exception, the Santa Maria valley. 
Everywhere these ■ beds have - been observed, they seem to have suffered extensively by 
denudation. In San Luis valley, towards the south, these strata merge into the San Lucia 
range, and shut up the valley in that direction. Around the town of San Luis, and north to 
the ocean, these soft strata have been removed, and have left only the harder conglomerate 
standing here and there as landmarks to indicate the former position of the strata. 
The history of these beds would he incomplete if notice was not taken of their occurrence upon 
the hills which form the divort between the valleys La Purissima and Santa Inez. In descend¬ 
ing this hill slope on the southeastern side, or entering the Santa Inez valley, the upper yellow 
slate was met, forming the sides of a canon down which the wagon road led to the valley ; on 
examining these shales, they were found to contain in places the impressions of numerous bodies 
