TERRESTRIAL DEPOSITS OF OWENS VALLEY 725 



clay, which contains enough lenses and pockets to give it a bedded 

 aspect. In other places it is made up of alternating layers of 

 gravel and clay, the latter containing bowlders in many places 

 (Fig. 14). 



Just below these coarse, roughly sorted materials on the main 

 road, the constitution changes abruptly to sandy clay, arranged 

 in continuous, uniform, apparently horizontal layers. The change 

 from coarse, poorly sorted conglomerates to fine clays takes place 

 within 500 ft. These clays appear all the way to the mouth of the 



- « —- - e -v 





• v '' : "v--- 



Fig. 15. — Lacustrine sand and clay in the Waucobi embayment. The layers are 

 continuous and of uniform thickness. 



canyon, as erosional hills about 100 ft. high, and in the valley 

 walls. Most of the clay is fine, becoming white dust when powdered. 

 Some layers are sandy and some calcareous. They are not usually 

 firmly cemented. Layers 1-10 ft. in thickness can be traced con- 

 tinuously along the hills (Fig. 15). 



These are doubtless lake deposits, the coarser marginal con- 

 glomerates being the littoral phase, and the centrally located clays 

 and sands having been deposited in quieter, deeper water, farther 

 from shore. The fossils have been determined by Dr. Dall as 

 Pliocene to recent. As the beds lie unconformably under Quater- 

 nary alluvium, they are probably Pliocene or early Quaternary 

 in age. 



