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adjustment of the region. It lies between five and ten miles back from the 
general scarp. Muddy Fork of Blue River flows west-southwest past 
Pekin, and as a graded stream is entirely in the Knobstone rocks. Muddy 
Fork of Silver Creek flows southeast, and is characterized by a barbed 
drainage pattern. This drainage is almost wholly in the Knobstone rocks. 
Only the long, tongue-like, inter-stream tracts S00 feet or more in eleya- 
tion are capped by the Harrodsburg. The slopes are steep and wooded, and 
are quite characteristic of Knobstone topography where it is in a much 
dissected condition due to minor stream development. The uplands be- 
tween Pekin and Martinsburg have a typical surface expression of the 
overlying Harrodsburg. The inter-stream tract east of Martinsburg reaches 
an elevation of about 950 feet, and is expressive of a remnant of the uplifted 
Tertiary peneplain, being capped by Tertiary gravels and sand. 
The valley of Muddy Fork of Blue River at Pekin has an elevation of T00 
feet, and seems to be in a graded condition. In the next fifteen miles the 
valley descends 100 feet, being approximately at an elevation of 600 feet at 
Fredericksburg. Drainage from approximately forty square miles flows 
past Pekin. Muddy Fork of Silver Creek heads in a number of steep ravines 
a short distance southeast of Pekin. These ravines are sharply trenched 
below the general level of the upland. Starting from an- elevation of 750 
feet in a broad, valley-like sag, a mere gravel and silt terrace above Blue 
River valley at Old Pekin, marking the lowest part of the divide be- 
tween.the two stream systems, one may make a rapid descent into Muddy 
Fork of ‘Silver Creek. A descent of 100 feet is attained in the first mile, and 
within one ‘and one-half miles the elevation is down to _ 600 
feet. This is the elevation of Blue River fifteen miles below Pekin. At 
Borden the valley of Muddy Fork of Silver Creek is down to an elevation 
of 560 feet. The stream here has developed a fairly wide, flat valley and 
is in a graded condition. 
The barbed drainage pattern of Muddy Fork of Silver Creek is a result of 
stream piracy. The parent stream of the present Muddy Fork of Silver 
Creek was a small stream flowing down the eastern face of the Knobstone 
scarp very similar to numerous others of the present time. Back-slope 
streams of the cuesta flowed westward from the crest of the escarpment. 
The position of the parent stream of Muddy Fork of Silver Creek does 
not appear to have been more favorably located for its development of head- 
ward erosion than many streams of the present along the escarpment. But 
for some reason it has succeeded in capturing practically the entire stream 
system of a large tributary that formerly flowed northwest and emptied 
into Blue River at Pekin. It would appear that after having once broken 
through the divide near the crest of the escarpment further capture of the 
lower tributaries followed in relatively quick succession. 
The drainage direction of the tributaries of Muddy Fork of Silver Creek 
coming in from the south between Borden and Broom Hill suggest that a 
single stream flowed to the northwest one time through sections 15, 12 and 
into section 1, and that this unit of drainage has been broken up by the 
