372 C. H. Gordon — Chalk Formations of Northeast Texas. 



Upon the outcrop of the chalk are located the towns of 

 Clarksville, Atlas, Roxton, Honey Grove, etc. Annona, the 

 town in Red River county from which the formation received 

 its name, lies several miles south of the outcrop of the beds. 



About three miles west of Clarksville, the exposures of 

 chalk and accompanying marls are interrupted by a covering 

 of Quaternary deposits, partly filling a broad shallow valley 

 excavated in the formation now occupied by the headwater 

 branches of Cuthand Creek. 



At Clarksville several wells have been extended through 

 chalk and underlying marls to the Blossom sands. No distinc- 

 tion is made in the well records between the marl and the 

 chalk, both being included under " white rock," which is said 

 to be about 600 feet thick. 



The outcrop of the blue chalk marls, called the Brownstown 

 marls, which underlie the Annona chalk, constitutes a belt of 

 black land, several miles wide, along the north side of the 

 chalk and bounded on the north by a strip of sands (Blossom 

 sands) representing the top of the Eagleford formation. The 

 thickness of the Brownstown in Red River and Lamar coun- 

 ties is estimated at 400 to 500 feet. It thins toward the west, 

 with a corresponding diminution in the width of outcrop, as 

 shown in Fannin county. Accompanying this change in the 

 thickness of the marls, there is an increase in thickness of the 

 chalks, the north boundary of which passes to the northward 

 of Honey Grove and thence to Sherman. 



The chalk beds occurring in the vicinity of Sherman have 

 generally been recognized as Austin. It is evident therefore 

 that the Annona chalk and the underlying Brownstown marls 

 are stratigraphically the equivalents of the Austin chalk. 

 The meager collections of fossils thus far obtained from these 

 formations in northeastern Texas offer little in the way of 

 faunal evidence bearing on the classification of these beds. 

 The collections thus far made indicate a wide range of the 

 species represented and no satisfactory conclusion can be 

 drawn from them. 



One hundred to two hundred feet above the Annona chalk 

 is another bed of chalk having a thickness of fifty to one 

 hundred feet. This chalk outcrops along the south side of 

 North Fork in the northern part of Delta county from the 

 vicinity of Enloe to the western boundary of the county. 

 The position of this chalk suggests its correlation with the 

 Saratoga chalk in Arkansas, which occupies a similar position 

 with respect to the Annona (White Cliffs) in that region. 

 There are no intervening exposures of chalk, however, and 

 the data from well borings seems to indicate that these upper 



