RECENT ALLUVIAL CHANGES IN SOUTHWESTERN IOWA. 
BY J. E. TODD. 
The region specially discussed in this paper is about five square 
miles in the northwest corner of Fremont county, Iowa, which is 
the southwest county of that State. It lies mostly on the bottom 
lands of the Missouri River. It is bounded on the east by a table- 
land rising abruptly in steep bluffs cut by deep ravines. These 
bluffs rise 250 to 300 feet above the plain and are composed mainly 
of yellowish loam, typical loess. This yields easily to erosion espe- 
cially when water soaked. At such times, its cementing lime, 
which when dry holds it firm like a soft rock is dissolved and the 
mass washes or creeps like wet sand. 
The map (Fig. 1) shows the main localities and features. Wa- 
bonsie Creek is ordinarily a stream 6-8 feet wide, where it comes 
from the hills. It has a basin about 27 square miles in extent 
above that point. Near its egress, around which cluster most of 
the facts we record, are two lakes, the North or Buckingham Lake 
and the South or Wabonsie Lake. These were doubtless once 
portions of the bed of the Missouri River, possibly about the same 
time, but more likely the south lake is the older, the north corre- 
sponding in time to an old channel northwest of the south lake. 
The turning of the river to its east bluffs at that time may be 
referred to the influence of Calument Point which stands out con- 
spicuously from the Nebraska side. 
It will be found advantageous to narrate the facts recorded, in 
the order of discovery, rather than in chronological order of their 
occurrence. 
The writer’s earliest personal acquaintance with the region was 
in the early sixties, when he fished in the south lake from the foot 
of the bluffs near the south line of section 11. At that time no 
road was possible along next the bluffs southward. Wabonsie 
Creek followed the bluffs closely in that direction, but old residents 
claim that it did not enter the lake but turned west to a channel 
northwest of it. 
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