Reid.] 



The Igneous Rocks near Pajaro. 



175 



rock in the anticlinal axis. On either side are overlying 1 sedi- 

 mentary rocks, to the west dipping gradually under the valley 

 soil, and to the east buckled into another similar fold. The fold 

 next to the east, however, is exposed only as far south as the 

 river; south of that lies the San Juan valley. 



It is at the elbow of the river above mentioned, and at the 

 railroad bridge a quarter of a mile southeast, that the nature of 

 the overlying sedimentary rocks is best seen. 



At a point a few yards east of the railroad bridge is found 

 the synclinal axis separating the ridge mentioned from the one 

 to the east. From this point to the elbow of the river these 

 sedimentaries dip at angles varying from from nearly 90° to 40° 

 to the east. They are of soft white shales, with some medium- 

 grained yellowish sandstone near the bottom, all rather thinly 

 bedded. On the west flank of the ridge near the quarry are 

 found the same series, but nearly all removed by erosion. The 

 sandstone near the base is well exposed, however, dipping 40° to 

 the west. To the north of the quarry, on the west flank of the 

 ridge, the transverse canons all through the anticlinal axis and 

 beyond the syncline already mentioned, show a well developed 

 sequence of coarse, rather thickly bedded yellowish sandstone 

 below, and white shales, thinly bedded, above. Three miles 

 soiith of the quarry, on the i - oad from Watsonville to San 

 Juan, the same coarse, heavy-bedded, yellowish sandstones appear 

 on the summit of the ridge. The road here passes through what 

 appears to be the old worn channel of a fairly large stream, 

 being bounded on both sides by water- worn cliffs of sandstone. 



No fossils were found in this series of sandstones and shales, 

 hence its age is somewhat uncertain. In lithological characters, 

 however, it corresponds well with the rocks of the lower Mon- 

 terey. Future research will probably show its close relation to 

 the rocks of this series. 



At the quarry, on the west slope of the ridge, is found a later 

 overlying series of friable sandstones, non-coherent sands, and 

 heavily bedded shales. These rocks lie across the truncated 

 edges of the first named series and upon the worn surface of the 

 igneous rock. The sandstone and loose sands, showing the 

 characteristic cross bedding of beach sands, lie lowest, and are 



