80 Kansas Academy of Science. 



much used for sidewalks. The shale between these limestones is 

 very rich in fossils. 



(11) Elmdale Beds, 150 feet. One-third of the thickness of 

 these beds is limestone, and the remainder is shaly limestone and 

 shale. Of these limestones, three deserve special mention : The 

 Friable Fusulina, twenty-four feet above the base of the beds, con- 

 tains myriads of rhizopods. The Neva limestone, forty-six feet 

 below the top, is twelve feet- in thickness. The upper half was 

 named "cotton rock" by Swallow, an early Kansas geologist, and 

 the lower half was named "dry bone;" from its peculiar appearance 

 when weathered. The Cottonwood limestone, twelve feet from the 

 top of the Elmdale beds, is one of the most highly valued building 

 stones of middle Kansas. It is a white limestone, and lies in a 

 stratum six and one-half feet in thickness. The twelve-foot shale 

 bed above this limestone is literally full of fossils and becomes ex- 

 cellent soil on decomposition. 



The Elmdale beds lie at the summit of the Coal Measures of 

 Kansas. No unconformity exists between these beds and those 

 above, but Permian fossils are increasingly abundant. 



III. ROCKS OF THE PERMIAN PERIOD OF THE CARBONIC ERA. 



Thickness, 2375 feet. 



1.— Strata of the Lower Permian Epoch. 



The rock beds found in central Kansas. Thickness. 565 feet. ( The layers are described, 

 beginning with the lowest.) 



(1) Stro7ig City Beds, 180 feet. These include Crusher Hill 

 alternating shales and limestones, 140 feet. The limestones offer 

 little resistance to atmospheric influences, and, therefore, have little 

 influence on topography. The stratum next above is the Strong 

 flints (Wreford limestone), 40 feet. This formation is chiefly re- 

 sponsible for the Flint Hills of central Kansas, because of its power 

 to resist erosive agencies. The layers of limestone have been re- 

 placed wholly or in part by silicious material, and are much used, 

 when crushed, for railroad ballast. The Flint Hills, or, as they were 

 named by the earlier geologists of Kansas, the Permian mountains, 

 extend across the state from Nebraska to Oklahoma, but are best 

 developed in Chase, Greenwood, Butler, Elk, Cowley and Chau- 

 tauqua counties. 



(2) Florence Beds, about 159 feet. These consist of Cedar 

 Point ( Matfield ) shales and shaly limestones, about 92 feet ; Flor- 

 ence flints and shaly, buff limestone, 37 feet ; Fort Riley ( Florence) 

 limestones, 30 feet. In the midst of the Florence flints are one or 

 two heavy layers of white limestone, quarried at El Dorado for fine 



