WICHITA FORMATION OF NORTHERN TEXAS 113 



Academy of Science, Cummins announced the discovery of evidence 

 showing that the limestones of eastern Baylor County are the same 

 as those of the "Albany." In this paper the beds of Baylor County 

 are said to constitute the upper part of the Wichita. Owing to 

 the discontinuance of the Texas Survey the report on this area 

 prepared for the Fifth Annual Report has not appeared. 



Rocks of the Wichita area. — East of Baylor County the rocks 

 consist for the most part of red concretionary clays, red sandstones 

 and sandy shales with occasional beds of blue shales, and bluish 

 to grayish- white sandstones. Limestones are conspicuously absent. 

 Occasional impure nodular layers occur, however, which contain 

 considerable calcareous matter, but these do not constitute strata 

 of limestone. The sandstones are usually soft and distinctly cross- 

 bedded. In some places they are shaly, in others massive. Some 

 layers are streaked and specked with grains of black iron oxide, 

 while others contain nodular masses and concretions of iron ore. 



The clays are mostly deep red or red mottled with bluish-white 

 and drab colors. The red clays contain an abundance of nodular 

 concretions of irregular shape varying in size from that of a pea to 

 masses 4 or 5 inches in diameter. They consist of clay, iron, and 

 lime, and at times are hollow or with the interior filled with cal- 

 careous clay or lime carbonate. In some cases they are flattened 

 and stand in vertical position in the clays, suggesting their origin 

 through the filling of fissures. 



Occasionally a bed is met with consisting of rounded lumps of 

 hardened clay cemented together by ferruginous matter, repre- 

 senting what Cummins called "a peculiar conglomerate." This 

 formation is believed to have had its origin in the breaking-up of a 

 bed of clay by running water or wave action. 



In places the bluish clays are copper bearing. Efforts to mine 

 these deposits, however, have not been profitable. The ore occurs 

 in the form of small nodules in the clays and also as a replacement 

 of wood. 1 



In the sandstones occasional traces of plants occur, and some- 

 times remains capable of identification are found. White reports 

 Taeniopteris from the sandstones near Fulda. The stratification 



1 J. F. Cummins, First Annual Report, Geological Survey (Texas, 1889), 188-96. 



