JAMES RIVER SECTIONS. 75 



I. Section at Drewry's Bluff. 



Feet 



Pleistocene Argillaceous, ferruginous sand 6 



Gravel bed 5 



Lower Cretaceous. Patuxent Light gray coarse, arkosic sand 5-20 



Similar materials much cross-bedded and carry- 

 ing gravel, cobbles, and clay balls 5-15 



Dark drab clay lenses in sand 5-10 



Indurated arkosic sand 12 



Coarse, arkosic, cross-bedded sand with clay 



balls and cobbles 15 



Total 53-83 



As previously mentioned, the materials change so rapidly from point to 

 point that no two sections of the bluff would be identical. The clay lens 

 near the middle of the outcrop is very variable and the cobbles frequently 

 tend to become aggregated into lenticular masses. Indurated layers a foot 

 or two in thickness are also irregularly scattered through the bluff. 



The next exposure is at Chaffin Bluff along the left bank one mile below 

 the last. 



II. Section at Chaffin Bluff. 



Feet 



Pleistocene Ferruginous, sandy clay 15 



Bed of cobbles 5 



Lower Cretaceous. Patuxent Gray, arkosic sand 10 



Dark drab clay 15 



Total 45 



This section also is extremely variable horizontally. 



The next exposure about three miles below the last is along the right 

 bank a short distance below Proctor Creek where the Patuxent is overlain 

 bv a remnant of Eocene materials. 



III. Section below Proctor Creel-. 



Feet 



Pleistocene Argillaceous, ferruginous sand about 10 



Course gravel with cobbles 8-10 



Eocene Glauconitic sands 5 



Lower Cretaceous. Patuxent Indurated, coarse, arkosic, cross-bedded sands. 10-15 



Total :33-40 



