WA THE JOURNAL OF GEOLOGY. 
the Strong flint, which varies in thickness from 35 to 45 feet 
Frome1roto 115 feet above they base toOmmtheRsinomeen intetsm tne 
base of the second massive flint with a heavy limestone above. 
The horizon is well exposed along the McPherson branch of the 
A., T. & S. F. R. R., and in the Jones’ quarries from one to two 
miles northeast of Florence. This may be called the Florence 
fiint and limestone. ‘The flint strata are 22 feet thick and are sep- 
arated near the center by a white cellular limestone from one to two 
feet thick, while above the flint are 4o feet of buff limestone, the 
lower and upper portions of which are generally more or less shaly, 
with a massive ledge forming the central portion. The highest 
flint and limestone is well exposed along the bluffs of the river 
and small streams near Marion, and its base is about 123 feet 
above the base of the Florence flint. Near Marion at the base of 
the flint horizon is a flinty limestone about 4 feet thick, followed 
by 13 feet of yellowish shales, capped by a zone 10 feet thick, 
composed of two strata of limestone separated by shales, the 
limestones containing large irregular concretions which weather 
to a brown color. The flint is not as uniform in occurrence as in 
the Florence and Strong flints, so at some localities this horizon 
is represented simply by a prominent light gray limestone nearly 
free from flint, and occasionally the particles in the concretion- 
ary limestone are small and inconspicuous. As a rule, however, 
the concretions are large and the stratum may be readily traced 
across the country either from its exposure in bluffs or streams, 
or from the line of loose brown concretions crossing the prairie. 
This limestone has been traced by the writer along its line of 
outcrop from the center part of Butler county across Chase and 
Marion counties into Morris county. 
This flint and concretionary limestone is the highest prom- 
inent flint ledge in the upper Paleozoic of Kansas. It forms a 
marked stratigraphic horizon that is of great assistance in deter- 
mining the areal geology of eastern central Kansas, and on 
account of the good exposures of this zone near Marion City, 
the horizon has been called the Marion flint and concretionary 
limestone. 
General geologic section of the Chase formation—Y¥rom the 
