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STUDIES FOR STUDENTS 



5. Distributed in belts (river iiats and piedmont alluvial plains). 



6. Bedding planes dip in one general direction, though slightly divergent 

 in the direction of general dip. 



7. Beds dip at angles varying up to 18"^. 



8. Deposit diminishes uniformly in thickness in the direction of the 

 divergence of dips. 



9. Material likely to be heterogeneous, lithologically. 



10. Pieces angular or rounded. 



11. Fossils rare, and of terrestrial forms. 



Fig. 2. — -A typical fluvial deposit, showing lens and pocket structure. A section 

 of a stream terrace in Jo Daviess County, 111. 



The lens and pocket structure seems to be especially character- 

 istic of fluvial deposits. In Owens Valley no textural division in 

 the fans could be traced more than fifty feet in any direction. 

 This structure is quite unlike the layered character of still-water 

 deposits such as those laid in lakes or in the sea, and somewhat 

 different from the structure of materials deposited by ocean or 

 lake waves and currents. The 18° of No. 7 above is the highest 

 angle read on the surface of the fans. The slight divergence of 

 dips as stated in No. 6 is due to distribution of the streams. Fig. 2 



