ADAMS: PHYSIOGRAPY OF SOUTHEASTERN KANSAS. 93 
anywhere discontinued or lose their importance the escarpment 
fades out, and the softer beds add their thickness to the escarpment 
geologically next higher. Likewise if the softer strata give place 
to more resistant ones, e. g. a limestone system appears in a posi- 
tion where in other cases there is a shale bed, a new escarpment is 
developed. If a shale bed gradually thins out the adjacent lime- 
stones are merged into the same escarpment, and, on the contrary, 
if two closely associated systems are separated at any place by the 
thickening of the intervening shales, their lines of outcrop diverge 
and two escarpments are produced. 
A stream flowing upon a back slope will gradually slide down 
upon the inclined strata until it reached the base of the next 
escarpment, cuts through the underlying formation, or reaches 
base level. In the latter case it would widen its valley, producing 
a plane independent of the dips of the strata. Along a single 
stream this area would be called a bottom land. When produced 
over a large area by a stream and its tributaries, or by several 
streams it 1s called a low land. 
The Prairie Plains region in Kansas is coextensive with the 
Carboniferous formation. Were a section made from Galena to 
Grenola it would pass across the entire formation as here exposed. 
At its eastern limit we have the break in geological time marked 
by unconformity, at its western limit the transition to the Permian 
is marked by the fossils only. The dip of the strata and the 
alternation of the easily eroded shales and sandstones with the 
more permanent limestones, is well exhibited by such a section 
drawn to scale. The lines of outcrop of the lmestone systems 
have been traced with considerable detail and are quite identical 
with the escarpments which are shown in the accompanying map 
(page g2). It will be observed that they trend in a northeast 
and southwest direction with many sinuosities where they cross the 
streams and divides. 
DESCRIPTION OF PHYSIOGRAPHIC FEATURES. 
Proceeding now to a description of the physiographic features 
and beginning with the southeastern corner of the state we find a 
small area of Sub-Carboniferous which belongs to the Ozark region 
and which forms our starting point (see map page g2). To the 
west of this lie 
THE CHEROKEE LOW LANDS. 
The base of the Carboniferous consists of a bed of shales and 
