STRUCTURE OF THE DRIFT BORDER. 67 



are well represented, and bowlders 4 feet in diameter are occasionally 

 found on the immediate drift border. 



Reference will be made to a few of the wells showing thick drift and 

 to characteristic exposures, beginning in Posey County and passing 

 northeastward. 



The thickest drift noted in Posey County is in an abandoned valley 

 which connects the head waters of Big Creek with Black River. One well 

 in this valley, on the farm of Joseph Nesbit, about a mile west of Cynthiana, 

 penetrated 127 feet of drift, and entered sandstone at that depth. The well 

 mouth is only about 420 feet above tide and 80 feet above the neighboring- 

 portion of the Wabash River. The driller, T. F. O'Herron, of Haubstadt, 

 reports that the entire depth is a stiff clay, of which the upper 36 feet has 

 a brown or yellow color, and the remainder a blue color. On a neighbor- 

 ing farm, owned by Joseph Cale, a well reached a depth of 114 feet without 

 entering rock. In this well two thin beds of fine gravel were passed 

 through. Aside from these the drift is a stiff clay, of which the upper 40 

 feet is yellowish brown and the remainder a blue color. 



On the head waters of Big Creek, in northwestern Vanderburg County, 

 several wells 40 to 60 feet in depth do not reach rock. This valley appears 

 to have been silted up to a depth of 50 feet or more in the portion imme- 

 diately outside the glacial boundary. Wells there are reported to pass 

 through " clay and quicksand." 



In the vicinity of Haubstadt, within a mile north of the glacial bound- 

 ary, there is a plain in which several wells have penetrated 40 to 70 feet of 

 drift before entering rock. The upper 20 or 30 feet is yellowish-brown 

 clay and the remainder blue clay. Occasionally the clay maintains a yel- 

 low color to a depth of 40 feet or more. The loess in that region, both 

 outside and inside the glacial boundary, is about 12 feet in thickness and is 

 similar in color to the oxidized portion of the underlying glacial drift. 



In the ridged belt near Fort Branch there are several hillside exposures 

 showing a few feet of till with considerable stony material just below the 

 loess, and beneath this a fine sand. The wells along the ridge enter a soft 

 blue clay, called "blue mud," at a depth of 30 or 40 feet. Only one well 

 was found which entered rock. This is located at the residence of Lawrence 

 Byers, near the east base of the ridge, and reached rock at a depth of 97 

 feet. Several wells along the crest of the ridge, 50 to 100 feet in depth, 



