THE PLAINS PROVINCE 89 



In 1909, Beede^ gave the following account of the transgression of the 

 red color into the limestones : 



"The limestones do not all continue to the southern limit of Kansas, some 

 of them pinching out before reaching- the Oklahoma line and others soon after 

 crossing it. Few of them pass beyond the Arkansas River in that State. It 

 seems that the central part of the Kansas Basin may have been to the north- 

 westward during later Pennsylvanian time, since the shales frequently become 

 thinner, and the limestones thicker in that direction, though this can not be 

 said of the lower part of the section. Above the Americus limestone the succes- 

 sion of limestones and shales continues for about 700 feet. However, the shales 

 become more calcareous and marly, the limestones more porous and less crystal- 

 line; massive gypsum beds are intercalated, and coal in quantities is wanting. 

 The limestones also weather white. These changes are significant of decided 

 physical or climatic changes, as the local pools of the lower horizons showed no 

 tendency to concentrate and form massive gypsum deposits. Probably, also, 

 the changed aspect of the limestones is indicative of these altered conditions. 

 The first large deposits of gypsum occur just above the Cottonwood limestone 

 in the lower part of the Garrison formation (Neosho member). Above these are 

 the Wreford limestone, Florence flint, Fort Riley and Winfield limestones, heavily 

 charged with chert, and separated by thick layers of shale. The outcrops of 

 these formations form the 'Flint Hills' of the eastern part of central Kansas. 

 Over these strata are two soft limestones with three intervening shale beds and a 

 variegated, brecciated, thin limestone. These are grouped in the Marion stage, 

 and end the regular succession of limestones and shales. Over the rocks of the 

 Marion stage lie the Wellington shales, probably several hundred feet in thickness, 

 composed of blue, green, and some red shales. Upon these shales lie 1,400 feet 

 of red beds in Kansas. The upper part of the Red Beds does not occur in Kansas, 

 but is found in western Oklahoma and the Panhandle of Texas. 



"The whole of the lower succession of shales and limestones forming lowlands 

 and low escarpments divide this section of continuous sedimentation into short 

 stratigraphic units of great lateral extent convenient for paleontologic study. 



"In Oklahoma different conditions prevailed during much of the time repre- 

 sented by the Kansas deposits, above the Cherokee shales. 



"Passing. from Kansas to Oklahoma, the light-colored shales and limestones 

 of the upper part of the Kansas section grade off into red shales and sandstones. 

 The lowest horizon in Oklahoma at which the red sediments predominate is 

 unknown, inasmuch as the strike of the rocks is but little west of south, and the 

 Red Beds protrude eastward in central Oklahoma as a sort of embayment, 

 especially north of the Arbuckle Mountains. 



"In the region south of the western end of the Arbuckles the Red Beds lie 

 unconformably upon the tilted and eroded Pennsylvanian rocks. It appears 

 that the Albany-Wichita sea of northwest Texas transgressed over this region 

 during a time of slight depression, the waters covering the western end of the 

 Arbuckle Mountains, swinging eastward on their northern slope as far as the 

 Seminole country. According to Cummins, there is no unconformity in Texas 

 between the lighter sediments and the Red Beds, the transition between the 



^ Beede, J. W., The Bearing of the Stratigraphic History and Invertebrate Fossils on the 

 Age of the Anthracolithic Rocks of Kansas and Oklahoma, Jour. Geol., vol. xvn, p. 

 712, 1909. 



