campbell.] GEOLOGY ALONG ROUTE TRAVERSED. 11 
to this range of mountains. It seems probable that movements so 
profound would have an appreciable effect on sediments lying on the 
southern edge of the desert, but no such effect is soon in the horizontal 
lake deposits 8 or 10 miles north of Cajon Pass. It is therefore prob- 
able that the beds in Cajon Canyon were deposited and folded prior to 
the existence of a lake in the desert near Victor. 
That this region has undergone profound changes since the disap- 
pearance of the lake in the vicinity of Victor is shown by the elevation 
of the great mountain mass south of the Lone Pine Canyon fault to its 
present position, by the accumulation of gravel on the southern margin 
of the desert to a thickness of 1,000 feet, and by the depression of the 
granite range several hundred feet below its former level. 
Mohave Desert or Victor. — The summit of Cajon Pass has an altitude 
of 1,100 feet, and it is formed of the gravel beds just described. In 
passing into the desert the road descends over the surface of the gravel 
at the rate of about 100 feet per mile. The gravel grows gradually 
thinner and finally disappears, leaving the surface composed of beds 
of fine material, lying in a horizontal position. 
These beds are made up of sand and clay sufficiently indurated to 
stand up in nearly vertical cliffs along Mohave River. They carry 
alkaline salts, but, so far as known, no borax has been found in them. 
The presence of alkaline deposits seems to indicate clearly that the 
body of water in which they were deposited lay in an inclosed basin, 
and that at times the aridity of the climate was so great as to cause the 
water to evaporate, leaving its alkaline constituents on the floor of the 
basin. 
No fossils have been found by which to determine the geologic age 
of these beds. They have been classed as Eocene and correlated with 
beds of this age in the western end of Mohave Desert; but the latter 
carry a marine fauna, and are therefore not. necessarily of the same 
age as the lake beds at Victor. As previously mentioned, the writer 
feels inclined to correlate the marine Eocene of the western Mohave 
Desert region with the beds in Cajon Canyon and to refer the lake 
beds of Victor to a later epoch. It seems possible that Victor Lake 
was one of a long string of lakes reaching across the country ju-t east 
of the Sierra Nevada, which Mr. Clarence King" called the Pah-Ute 
Lake of the Miocene epoch; or it may have been in existence during 
the deposition of similar beds north of Owens Lake, in which Mr. 
Walcott discovered fossils of Pliocene age/ 
At Victor the lake beds are confined to the territory lying west of 
Mohave River. According to Mr. Spurr'' this relation holds down 
the river at least as far as the point where the course changes from 
"C s. Geol. Expl. Fortieth Par., Vol. I, p. 154. 
&The post-Pleistocene elevation of the Inyo Range and the lake beds of Waucobi embayment, Inyo 
County, Cal.: Jour. Geol., Vol. V, \>\>. 340-349. 
c Unpublished manuscript. 
