DESCRIPTIONS OF FORMATIONS 467 



determinable fossils except plant remains have been secured from these 

 beds, and while good collections were made we have as yet no definite 

 information as to the exact age indicated by them. 



Stratigraphically, this group is post-Jackson. Lithologically, the base 

 corresponds closely with the typical Grand Gulf, while the top is very 

 similar to the Oakville beds of the Nueces section, and up to the present, 

 in the absence of determinable fossils other than plants and on account of 

 the apparent stratigraphic connections, it has seemed to the writer that 

 the group represented a remnantal area of Catahoula overlain or sur- 

 rounded by the Oakville. Baker and Suman did not find any basis for 

 such a division of these beds, but regarded the observed unconformities 

 as local only, and, in view of the age of the fossils found in beds overly- 

 ing the Corrigan, it may be that this opinion is no longer tenable as a 

 whole. It now seems probable that the Corrigan represents some portion 

 or all of the Oligocene above the Vicksburg (which is wanting in this 

 area), and that while the base may be Grand Gulf the upper portion is 

 probably later. 



FLEMING 



South of the Corrigan sands and overlying them there occurs a broad 

 belt of clays and sands, with quantities of calcareous concretions, which 

 were called by Kennedy the Fleming clays. They occupy a belt from 15 

 to 25 miles in width and are followed by the deposits referred to the 

 Lafayette or Eeynosa. Since no clear basis for the division of these beds 

 was found, the name Fleming as used here includes all sediments between 

 the Corrigan sands and the Lafayette between the Sabine and Navasota 

 rivers, and these were mapped as a unit, although they probably comprise 

 deposits of both Mioceiie and Pliocene age. 



Burke^■ille is near the base of the Fleming clays as exposed in the 

 region near the Sabine liiver. Baker describes the deposits here as fol- 

 lows : 



"In color the Fleming is most generally a light shade of grayish or yellowish 

 green, often weatlieriug brown on the surface. The surface, when dry, is 

 cracked like ordinary plastic clay. The material is fine clay and clayey sand, 

 with small whitisli limestone concretions. However, there are, at Burkeville, 

 larger grayish brown, very fine-grained limestone concretions with dendritic 

 markings of manganoso dioxide, concretions of fine- to medium-grained sand- 

 stones, of large size and rough, irregular outline; and the fossiliferous breccia 

 or beach limestone conglomerate known oidy from one-half mile east of Burke- 

 ville and soutli of Little Cow Creek, where fragmentary bones of land mam- 

 mals and l)raclvish water mollusks were found. In many places the small 

 white concretions are arranged in thin beds parallel to the imperfect lines of 

 stratification. The fine sands are also locally finely laminated and cross- 

 bedded." 



