BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA 

 Vol. 26, pp. 447-476, PLS. 25-27 DECEMBER 4, 1915 



PROBLEM OF THE TEXAS TEllTIARY SAXDS ' 



BY E. T. DUMBLE 



(Bead before the Socief;/ Aui/usI ■">. IDhl) 



CONTENTS 



Page 



Introduction 447 



Review of previous worl-c 449 



Recent examinations- 457 



Descriptions of formations of east Texas 459 



Lower Claiborne 459 



Yegua 459 



Fayette 460 



Frio » 461 



Upper Claiborne , 461 



Jackson 461 



Corrigan 465 



Fleming 467 



Summary ., 473 



Possible equivalency 476 



Introductio.\ 



In connection with the Oulf Tertiary deposits, which stretch entirely 

 across the Coastal Plain of Texas, there is a narrow helt within which 

 the outcrops of several distinct sandy formations are exposed. The shore- 

 ward margin of this belt averages about 100 miles from the present Gulf 

 coast. The belt is sometimes less Ihnii l<i miles in width, very rarely 

 widens to more than 20 miles, and reaches its broadest exposures of about 

 40 miles only on the Xueces and iiio Grande. 



There are five of these sands. They are very similar in composition 

 and appearance, fossils are comparatively rare in them, and it is often 

 diillcult to distinguish the one from the other, especially where the sands 

 of one division overlap and ai'c in liircct contact with another. 



These sands, in descending order, are : 



'Manuscript rocoivcd by Iho Socrotary of tlio Socloty Octobnr 1.3, 101.".. 



(447) 



