192 G. I. ADAMS RED BEDS OF NORTHERN TEXAS 



portion in strike with the Permian limestones is of Permian age. The 

 stratigraph)^ of the Red beds is difficult to study because of the absence 

 of conspicuous horizons and the general absence of fossils. It is be- 

 lieved, however, that the results of the reconnaissance supply a correct 

 interpretation of the beds and furnish a basis for future detailed study 

 of them. 



After having arrived at the conclusions above stated concerning the 

 relation of the Red beds in Oklahoma, the writer was impressed with 

 the idea that similar features might be found in northern Texas. Ac- 

 cordingly a trip was made in the month of October, 1902, for the pur- 

 pose of reviewing that field and studying the critical points in the 

 mapping which had been done by the Texas survey. The writer was 

 accompanied b}^ Mr Bailey Willis during a portion of the time, and has 

 had the benefit of his criticism and suggestions. 



Results of Cummins's Investigations 



The relation of the Carboniferous and Permian limestones of northern 

 Texas to the Red beds in that region as first explained by Mr W. F. 

 Cummins,* of the Texas surve}^ has never appeared wholly satisfactory. 



The accompanying sketch map (figure 1) has been prepared from the 

 published maps and sections made by the Texas survey. It will be 

 observed that certain of the divisions of the Carboniferous seem to have 

 been difi'erentiated by correlating sections made across the strike of the 

 beds, and that the sections in the northern part of the field do not tie 

 to each other. Mr Cummins first expressed doubt as to the accuracy 

 of his earlier mapping, f and finally reviewed the field in part and sup- 

 plied a more satisfactor}^ interpretation. His conclusions, which are 

 corroborated by the results of the writer's reconnaissance, are stated 

 b}^ him in a preliminar}^ paper,J but his fuller paper has not yet been 

 printed by the Texas surve3\ It is not proposed here to review the 

 somewhat conflicting statements which have been published concerning 

 the relation of the Albany and Cisco to the Wichita and Clearfork divis- 

 ions, but to proceed at once to the interpretation of the stratigraphy 

 which was arrived at from a study of the field. 



Reconnaissance in northern Texas 



It was considered advisable to examine at several points the Carbon- 

 iferous-Permian contact as mapped by Mr Cummins in the second annual 



* Report of geology of northwest Texas. Second Annual Rep't Texas Survey, 1890, pp. 359-555. 



t Texas Survey, vol. iv, p. 223. 



I Trans. Tex. Acad. Sci., 1897, p. 93. 



