108 University Geological Survey of Kansas. 
the state measures from 40 to 50 feet. In Greenwood county 
the lower limestone is separated farther from its companions, 
and by the time Longton is reached in a southward journey it 
is found to be 60 or more feet away and thins out so that it was 
nowhere seen south of that town. Likewise it was not found 
north of Atchison. 
Area.—From the relations of the different limestone masses 
constituting the Oread limestone, their outcropping lines form 
but one escarpment, which is very prominent from Doniphan 
county to Chautauqua county. The upper Oread limestone 
passes out of the state southward near Elgin and under the 
Missouri river on the north side of Doniphan county. 
Characteristics.—The upper of these Oread limestones is a 
gray rock throughout its extent, but somewhat darker at its 
southern end than elsewhere. Chert nodules are very abun- 
dant in it. The lower limestone weathers buff to brown, but 
has an exceptionally light layer in the hills south of Lawrence. 
It carries a few chert concretions but not nearly so many as the 
upper. The thin middle limestone, although only 2 feet thick 
or less, has a persistency of lateral extent far beyond any 
reasonable expectation. It is continuous from the extreme 
north to the extreme south of the entire Oread outcroppings 
within the state. Very large slabs of this thin limestone cap 
the hills north of Sedan. It also forms the platform on the 
University campus, in front of Fraser Hall. The Oread lime- 
stones are quite hummocky in Elk and Chautauqua counties, 
forming dome-like hills with little irregularity, and are flexed 
near Yates Center, Woodson county, at the head of Owl creek, 
and also at Pomona, in Franklin county. The lower interven- 
ing shales are mainly olive-colored clays. The upper have a 
bituminous bed just above the middle limestone. And here it 
might be said that this bituminous bed is as persistent as the 
thin limestone below it from the extreme north to the extreme 
south. 
Kanwaka Shales.58 
The name Kanwaka shales was given by Adams to the shales 
occupying the interval between the Oread and Lecompton lime- 
stones, so named after a municipal township in Douglas county, 
where they occupy a large portion of the surface. 
Thickness.—The Kanwaka shales vary in thickness from 50: 
to 100 feet. 
58. Adams, Dr. George I.: U.S. G.S., Bull. 211, p. 45. Washington, 1908. 
