APPENDIX. 



577 



Section in Southern California. 1 



Names of Formations. 



Thickness 

 in Feet. 



Characteristics 



Alluvium, etc. 



1-100 



Clay and gravel. 



dune sand. 



10-400 ± 



Sand and gravel. 



Paso Robles forma- 

 tion. 



Unconformity ^-^ ^ 

 Pismo formation 



{in south part of 



area) . 

 Santa Margarita 



(in north part of 



area). 

 Unconformity -~-^^ 



Monterey shale. 



1000 + 



3000 ± 



1550 ± 



5000-7000 



Vaquero sandstone. 

 • Unconformity -^^~~ 



Atascadero forma- 

 tion. 



Unconformity ■> — ~~- 



Toro formation 

 (Knoxville.) 



Unconformity -~ — — - 



San Luis formation 

 (Franciscan). 



Unconformity ^^^ 

 Granite. 



0-500 



3000-4000 



3000 ± 



1000 ± 



Sandy and marly clay, with pebbly conglomer- 

 ate; fragments of Monterey shale at bottom. 



Sandstone and conglomerate at the base, 

 siliceous shale, diatomaceous earth, and soft 

 sandstone above. 



Alternations of conglomerate and sandstone, 

 with layers of diatomaceous earth and pumice. 



Thin-bedded bituminous shale, largely sili- 

 ceous, with diatomaceous earth in places; 

 carries oil and asphaltum. Toward base, 

 limestone, with volcanic ash below, and 

 sandstone at bottom. 



Sandstone and conglomerate. 



Sandstone with some conglomerate and shale. 



Dark clay shale, with irregular beds of conglom- 

 erate at bottom and near the middle. 



Chiefly sandstone, but locally much shale; 

 numerous radiolarian jasper lentils, and some 

 contact metamorphic schist. 



1 Fairbanks, San Luis folio, U. S. GeoL Surv, The Comanchean and Cretaceous are classed as 

 Cretaceous in the folio. 



