BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA 

 Vol. 34, pp. 541-560 September 30. 1923 



CEYSTALLI^^E EOCKS OF THE PLAINS ^ 



BY CHARLES N. GOULD 



{Presented hefore the Society December 29, 1922) 



CONTENTS 



Page 



Precambrian crystallines 541 



Crystallines of later age 543 



General statement 543 



Occurrences near the Rocky Mountains 543 



Occurrences in the Arkansas-Texas region 544 



Ohio Valley-Balcones line of disturbance 545 



Scattered occurrences of crystallines 547 



General statement 547 



Spavinaw Creek, Oklahoma 547 



Camden County, Missouri 548 



Woodson County, Kansas 548 



Riley County, Kansas 549 



Lamar, Colorado 549 



Subsurface crystalline rocks 550 



General statement 550 



Nemaha mountains 551 



Amarillo mountains 551 



Red River uplift 551 



Buried granite ridge in New Mexico 553 



Miscellaneous granite wells 553 



List of granite wells 555 



Discussion 558 



References 558 



Precambrian Crystallines 



A glance at the geological map of that part of the United States lying 

 between the Mississippi River and the Rocky Mountains will reveal six 

 regions of mountain uplift, namely, the Black Hills, the Ozarks, the 

 Ouachitas, the Arbuckles, the Wichitas, and the Llano Mountains (some- 

 times called the Central Mineral Region) of Texas. The general struc- 

 ture of all these mountains is essentially the same, being in each case a 



^ Manuscript received by the Secretary- of the Society February 7, 1923. 



(541) 



