460 University of California Publications. [Geology 



the east, between Caliente and the Tejon Ranch House, is itself 

 a fault scarp, and dates from about the same time as the fault- 

 ing which gave rise to Tehachapi, Brites and Cummings Valleys. 



BEAK VALLEY. 



Bear Valley lies to the northwest of Cummings Valley along 

 the base of the southwest scarp of Bear Mountain. Its longer 

 diameter is parallel to the line of the scarp and is about 3 miles 

 in extent. The general width of the valley is about 2 miles. Its 

 area is about 6 square miles. The valley is in two levels. Along 

 the immediate base of the southwest scarp of Bear Mountain is 

 a well denned terrace about 1000 feet wide mantled by the allu- 

 vial wash from the scarp which rises steeply at its rear This 

 terrace is bounded on the southwest by a rather sharp rocky 

 ridge which is in general less than 100 feet above the terrace, 

 and which is notched down to the level of the terrace in a num- 

 ber of places. On the southwest side of this ridge there is an 

 abrupt drop to the level of the main floor of the valley. The 

 latter has an altitude of about 4300 feet at the Fickert ranch 

 house. The terrace is from 300 to 500 feet above this, its highest 

 point being at its southwest end where the wagon road from Bear 

 Valley begins to descend to Cummings Valley. From this cul- 

 minating point the terrace slopes down to the northwest in the 

 direction of its extension. It is evident that this remarkable 

 feature is a fault terrace. It is a narrow strip of the mountain 

 mass lying between the main fault of the Bear Mountain scarp 

 and a subsidiary parallel fault, the scarp of which forms the 

 descent from the terrace to the main valley. The terrace prob- 

 ably sloped originally down toward the main Bear Mountain 

 scarp and owed that slope to rotation of the fault-bounded block. 

 The trough thus formed has since been filled by the debris shed 

 from the scarp above. In its essential features this narrow fault 

 block flanking a major fault scarp is identical with the kernbuts* 

 of the Upper Kern. The main portion of the valley below the 

 fault terrace is constricted near its middle by a narrow sharp 

 ridge of small height which projects as a spur from the moun- 



* Geomorphogeny of the Upper Kern Basin. Bull. Dept. Geol. Univ. 

 Cal., Vol. 3, No. 15, p. 331. 



