446 University of California Publications in Geology [Vol. 7 



possible that the south front represents a degraded fault scarp. 

 East of the Alvord Mountains lies the well-rounded dome of 

 Dunn Mountain, the mass of which appears to consist largely of 

 schist. East of Dunn Mountain rises Cave Mountain. Through 

 the south flank of this imposing granitic massif the Mohave River 

 leaves the Manix Lake basin by a gorge cut in part in volcanics 

 which overlie the granite. South of the Mohave River and east 

 of the Manix Lake basin stand the Cady Mountains, of the 

 geology of which little more was learned than that basic volcanics 

 occur in the higher parts and that rhyolites with well-developed 

 east-west slaty structure, probably of early Tertiary age, are 

 present along the western flanks near Camp Cady. A patch of 

 the older granite also is exposed in this vicinity. South of the 

 Pleistocene basin the Kane Mountains rise abruptly. Lavas occur 

 on their flanks and Campbell 7 describes beds which are probably 

 Rosamond extending eastward toward this locality from a point 

 south of Daggett. 



Pleistocene Panglomerates 



The initial stage in the history of accumulation in the Manix 

 Lake basin was the transportation of large quantities of coarse, 

 more or less angular rock-waste from the surrounding ranges, 

 to be deposited at lower levels. The character of these waste 

 deposits indicates their alluvial-fan origin and therefore the 

 term "fanglomerates" has been applied to them in accordance 

 with the meaning of that term as defined by Professor Andrew 

 C. Lawson." 



A fault near Field, and downcutting by the Mohave River, 

 with consequent backcutting by side gulches, have been the prin- 

 cipal means of exposing to view both the fanglomerates and the 

 Manix Beds. 



The fanglomerates were deposited on the lower range slopes 

 as well as on the valley areas, and are of greater areal extent 

 than the overlying horizontally deposited lacustral beds of Manix 



7 Campbell, M. E., Reconnaissance of the Borax Deposits of Death 

 Valley and Mohave Desert, U. S. Geol. Surv., Bull. no. 200, p. 12, 1902. 



s Lawson. A. C, The Petrographic Designation of Alluvial Fan Forma- 

 tions. Univ. Calif. Publ. Bull. Dept. Geol., vol. 7, no. 15, pp. 325-334, 1913. 



