730 ARTHUR C. TROWBRIDGE 



constant. No faults, minor folds, or other evidences of diastro- 

 phism were seen. This dip may be depositional, or the beds may 

 have been tilted to their present position by an uplift in the moun- 

 tains. Eighteen degrees is a high dip to be considered depositional 

 when the material is fine. 



4. The older deposit shows a tendency toward cementation, 

 and some layers are firmly cemented. In general it is the layers 

 of coarse material, originally more porous, that are cemented. 



In the beds east of Citrus mentioned under (3) above, the upper 

 layer of gravel is cemented to firm conglomerate. It is so solid as 

 to ring under the hammer and to need more than one hard stroke 



c • 



iii ma 1 ' i - . -*• --^ »• - ; 95 . ». •■ 



Fig. 20. — A stream terrace of older alluvium in Mazourka Canyon 



before it is broken. The material of the finer layer below cannot 

 be picked out by the hand, but yields readily to the hammer. The 

 gravel layers are almost everywhere so indurated that they stand 

 out conspicuously, the determination of dips thus being made easy. 

 The above characteristics hold for all the deposits of older 

 materials at the foot of the mountains, with the exception of those 

 in Mazourka Canyon. The deposits in this canyon belong to the 

 older deposit, for they occur in terraces above the present deposi- 

 tional surfaces, but the materials are in some respects different. 

 Areally considered they take the form of the canyon in which they 

 were deposited, and thus occur in a long strip. They constitute 

 more or less definite stream terraces on the sides of the present 

 valley (Fig. 20). Texturally they are like the deposits along 

 the foot of the mountains, the chief difference being in the strati- 



