SECTIONS ALONG THE MATTAPONI RIVEK AND ITS TRIBUTARIES. 137 



IV. WaU:erton. 



Just below the mill dam there is a thickness of 17 feet of diatomaceous 

 earth exposed. This lies below the shell marl described as occurring 4 

 miles northwest and 3 miles northeast of Walkerton. From roadside 

 exposures observed near Walkerton it seems that there is a thickness of 

 perhaps 30 feet of yellow or blue sand between the diatomaceous earth 

 and the shell marl. 



V. Mattaponi River between Walkerton and West Point. 



For several miles below Walkerton the diatomaceous earth appears in 

 the banks frequently showing a thickness of 20 feet. The Pleistocene 

 covering is thin and consists of brown to gray sand with some small 

 pebbles. At White Oak Landing (right bank) the diatomaceous earth 

 is replaced by a blue earth which is intermediate between diatomaceous 

 earth and blue sand. At Mantapike Landing (left bank) the bluff is 

 about 20 feet in height and extends for some distance below. Although 

 largely concealed by vegetation the lower part of the bluff is seen to 

 consist of Miocene buff sand. 



At Newington (left bank of river) there is a bluff 18 to 20 feet in 

 height with some Miocene buff sand outcropping at the base. Between 

 Wakema, right bank (Frazier's Ferry), and Indian Town there is a high 

 bluff about 75 feet in height which is said to be the highest bluff on the 

 river. Landslides have obscured part of it but it seems that at least 50 

 feet consists of Miocene sand which is buff above (where weathered) 

 and blue below. At Courthouse Landing about 2 miles from King and 

 Queen Courthouse the bluff is about 45 feet in height. Blue Miocene 

 earth extends from water to a height of about 5 feet. Between Court- 

 house Landing and Clifton se'^eral low bluffs with blue Miocene earth 

 appear while the exposure at Clifton Landing (left bank) shows the blue 

 Miocene earth very well. Below Clifton Landing no bluffs exposing 

 Miocene were seen on the Mattaponi. A few low bluffs show Pleistocene 

 strata. 



VI. Section along road six and one-lialf miles southeast of Ashland. 



Feet 



Pleistocene Surface loam yellow and mottled 4 



Band of clay with small pebbles 1 



Brown iron sand with some clay 5 



Pebble layer (pebbles from 1 to 3 inches in 



diameter) 1-3 in. 



Miocene. Calvert Drab clay with many fossil casts, blue when 



fresh ( exposed ) 10 



Total 20^ 



