BURIED STRANDS OF LOP 



373 



stream after it had carved a channel 

 in the soft clays numbered 1 to 4. 

 Elsewhere along the sides of the mod- 

 ern gully where the section shown in 

 figure 13 is exposed, the whole of the 

 cross-section of the old channel can be 

 seen. The channel is cut in clay and 

 sand, and forms a typical fossil stream 

 bed of gravel several hundred feet 

 wide. Figure 13 shows how it hap- 

 pened that the old stream of figure 12 

 could cut so deep a channel. A-B 

 seems to be a battered lacustrine bluff, 

 cut by the lake when the water stood 

 some 50 or 60 feet above the present 

 level. The lake stood at this height 

 long enough to cut a bluff resembling 

 that of plate 33, figure 3. Later the 

 water rose above the bluff at various 

 times and the overlying strata were 

 deposited. 



It is impossible to assign a date to 

 the fossil bluff of figure 13. It was 

 certainly formed before the time of the 

 115-foot strand and probably before 

 that of the 300- and 600-foot strands. 

 As appears in figure 5, the strata above 

 the unconformity consist of ivro de- 

 l)osits of semi-lacustrine ami very saline 

 red clay separated by -41 feet of sub- 

 aerial deposits belonging to an unmis- 

 takable interlacustral epoch. The upper 

 layer of saline deposits lies well above 

 the 115-foot strand, and clearly ante- 

 dates it. The lower layer of saline de- 

 posits is, of course, still older. It may 

 be that the two were formed during the 

 300- and 600-foot epochs of lake ex- 

 pansion, although the red color seems 

 to he against this. In the present ab- 



