Vor. 111] ANDERSON—NEOCENE DEPOSITS OF KERN RIVER 79 
toward the west. From a nearer view they are seen to be 
very much dissected by erosion. The larger streams coming 
from the Sierra meander through the zone of foot-hills in 
sinuous valleys along narrow flood-plains developed by corra- 
sion in the yielding sediments. The intervening parts of the 
area are deeply cut by canons and ravines of varying gradients, 
which reproduce, in measures proportionate to their size, the 
features of the larger streams. As the general mesa-like 
surface rises gradually toward the east, so too, in going up- 
stream toward the basement formations, the canyons and their 
tributaries become deeper, and the hills higher and steeper. 
The effect is that usually produced upon yielding sandy forma- 
tions by recent but rapid degradation. The topography is 
similar to much that is found in the more arid belt along the 
western border of the Great Valley. 
The principal streams are the Kern and White rivers, Poso, 
Caliente and Tejon creeks, all of which derive their waters 
from the older areas of the Sierra, and descend thence through 
deep and narrow gorges, and enter the zone of foot-hills in 
rapids, below which the grade is quickly lost. With the excep- 
tion of the Kern River, these streams are without water during 
the drier portions of the year, while in the wet seasons they 
are often torrential. They cross the zone of foot-hills in rela- 
tively wide and shallow canyons, and have developed flood- 
plains that are in strong contrast to the narrow defiles in the 
older and harder formations. The canyon of Caliente Creek 
offers some interesting features which will be taken up later. 
RIVER-TERRACES 
The later erosional phases in the physiographic development 
of the region are well illustrated in the terraces along the 
several streams in the zone of the Tertiary hills. They are to 
be seen along all of the larger streams, but especially along the 
valley of the lower Kern. Within four miles of the point at 
which the river emerges from the granitic defile, five distinct 
terraces are to be seen above the present level of the river. 
Most of these terraces are shown in the plates at the end of this 
paper. Within the limits of these views they are found at 
elevations of 20, 60, 100, 160 and 350 feet above the level of 
the river. There are terraces at still higher levels, and rem- 
