SECTIONS IN THE YORK RIVER VALLEY. 161 



Two and one-half miles southwest of Money shell marl about 10 feet in 

 thickness is exposed along the roadside. Cham a congregata is by far the 

 most abundant fossil. 



Three-quarters of a mile northwest of Clopton, a layer of shell marl out- 

 crops along Carter's Creek just below the dam. In the vicinity of Gloucester 

 Point there is considerable marl which before the war was used extensively 

 on land, but little has been dug since then. At Bellefield on the south side 

 of the river the same is true. 



At the road crossing of Scimmino Creek mottled Pleistocene sand and 

 clay about 30 feet in thickness overlies about 25 feet of Miocene (Yorktown) 

 gray, iron-brown, and buff-colored sands in definite layers. In certain bands 

 there is considerable clay present. 



At the road crossing of Queen and Carter's creeks Miocene buff-colored 

 sand containing fossils is exposed in the bottom of the valleys. The over- 

 lying Pleistocene is about 25-30 feet in thickness and consists of mottled 

 (red, brown, and drab) clay grading downward into a cross-bedded sand. 



At the road crossing near the head waters of King Creek, a shell layer 15 

 to 20 feet in thickness is poorly exposed along the roadside. The great quan- 

 tity of Pecten jeffersonius and a few fragments of Pecten clintonius indicate 

 , that this layer is the same as that seen at the upper part of Bellefield and 

 1 mile below King's Mill on the James River. Some large species of Car- 

 dium were seen. Among the species represented at this locality are the 

 following: Area centenaria, A. incile, Astarte concentrica, A. symmetrica, 

 A. thispMUa ?, A. undulata, Cardita arata, Chama congregata, Crassaiellites 

 undulatus, Glycynieris subovata, Ostrea compressirostra, Pecten jejfersonius, 

 P. madisonius, Phacoides anodonta, Venus rileyi, Crucihuluui grande, Tur- 

 ntella variabilis. 



On Black Swamp Creek there is a shell layer exposed, consisting prin- 

 cipally of casts, with some decayed shells. It resembles the layer occurring 

 near the west end of Bellefield bluff. 



Section exposed along the right hanl- of Yorh River from. King's Creek 



to Wornilcy's Creek. 



Feet 

 Miocene. Yorktown Sandy gray shell marl: shells generally large 



bivalves badly worn, sometimes fragmentary. 

 Contains Crepidnia spinosa, Ostrea, perhaps 

 0. rirginica ; at Bellefield, Meliva maxiUata, 

 Pecten jeffersonius, P. clintonius, Glycynieris 

 subovata, Venus tridacnoides, V. rileyi, etc.. 10 

 Gray marl full of shells in some places becom- 

 ing fragmentary; contains A7ca incile, Car- 



