A STUDY OF A PORTION OF THE IOWAN DRIFT BORDER IN 
FAYETTE COUNTY, IOWA. 
BY GRANT E. FINCH. 
When a boy, living on the border between the Iowan and the Loe^s- 
Kansan drift sheets, the great difference between the two regions was 
very apparent to me then, and now, in the light of the extensive and inter- 
esting contributions to glacial geology in recent years, it is a pleasure 
to take a geological review of the scenes of my boyhood. It is my pur- 
pose to make a few observations relating to the Iowan drift border in 
Fayette county, Iowa, in particular the region between West Union and 
Fayette. 
The first and most apparent feature to the eye is the great and abrupt 
contrast in topography; the Iowan prairies, gently undulating, with 
broad and basin-like valleys, and abounding in boulder-bearing sloughs, 
the rolling Loess-Kansas region, a timber country so far as not yet 
cleared, with sharply-rounded hills, deep and often narrow valleys, and 
almost without sloughs or boulders. Leaving West Union by the east 
wagon road to Fayette, which crosses the railroad tracks just east of 
the round houses of the railroad companies, one can locate to the east 
the Iowan drift* border all along the way, almost without leaving the 
main road. The Loess-Kansan hills rise abruptly and with little tran- 
sition interval to separate them from regions of typical Iowan in topog- 
raphy, and can be easily seen and recognized a mile or more away. Were 
we to stand on the edge of the Loess-Kansan hills and look out across 
the Iowan drift the change would be no less conspicious. 
One of the very apparent features of the Iowan drift, as its edge is 
approached, is its sandy character. The wagon road just mentioned 
between West Union and Fayette is so sandy as to be poorly adapted for 
travel, especially to the cyclist or automobilist. This sandy zone is evi- 
dence of an outwash from the melting front of the Iowan ice. The 
farms of this region have a soil that is warm and quick but rather light. 
They w^ere the first lands to be settled after the occupation of the river 
bottoms. 
Where this sandy zone comes in contact with the edge of the Loess- 
Kansan there was no overlapping observed; either of the loess over the 
Iowan deposits or of the Io\van over the loess, a fact that would go to 
show simultaneous deposition of the two formations. 
Another interesting point for observation here is the undrained por- 
tion of the Iowan, known as “sloughs”. Any one who has lived in this 
region and dug post-holes, and plowed, knows that the higher ground 
contains fewer boulders than the sloughs, which are always plentifully 
dotted with “nigger-heads”, usually lying well up out of the ground. The 
slough soil is a tough, unassorted till. The up-lands are more sandy 
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