NEOCENE STRATIGRAPHY. 3OI 



being distinct. In other places the strata are very heavily 

 bedded, and frequently so intersected with joint planes 

 that it is difficult to make out the real bedding. In many 

 places these sandstones were observed to be peculiarly and 

 quite characteristically weathered, so as to give the surface 

 a pitted or honeycombed appearance, the cells being from 

 a fraction of an inch up to live or six inches across. The 

 resisting cell walls have probably been hardened by iron 

 which has infiltrated into the network of joint planes. At 

 Point San Pedro these strata lie upon the granite, and are 

 largely made up of granite boulders and fragments. The 

 proportion of granite increases as the main granitic mass 

 is approached, until it becomes difficult to recognize the 

 separating line. 



These two facies were not found occupying definite 

 horizons, but, as in the Pescadero section, grade into each 

 other, and succeed each other irregularly in the vertical 

 section. 



The third facies is more characteristic. It is a con- 

 glomerate, heavy bedded, and apparently made up of the 

 rocks of the metamorphics, fragments of phthanite being 

 particularly abundant. This conglomerate is usually quite 

 hard, the included fragments breaking across where a 

 piece of the rock is fractured. The rock is usually brown 

 or dark colored, except where relieved by the red or other 

 colors of the phthanite. The pebbles are usually not 

 very large, varying from an inch or under to three or four 

 inches in diameter. They are frequently found to be dis- 

 tinctly faulted. 



The conglomerate of Carmelo Bay is laid down upon 

 granite and contains considerable granite, which the con- 

 glomerates of the Santa Cruz Mountains do not, as far as 

 observed. This is, however, due to local conditions and 



