SUBSURFACE CRYSTALLIXES 551 



members of the geological fraternity are gradually accumulating a vast 

 amount of useful information. 



Ten years ago relatively little was known regarding the subsurface 

 formations of the Great Plains. Academically, the geologist knew, of 

 course, that granite or other crystalline rocks underlaid all this region, 

 but little was known as to the character and thickness of the sedimen- 

 taries. Occasionally a driller reported granite in a deep well, but at that 

 time neither the oil man nor the geologist paid much attention to his 

 statements. 



XEMAHA M0UXTAIX8 



During the years 1914-1915 several wells located on well-defined anti- 

 clines in northern Kansas began to encounter crystalline rocks, and since 

 that time something like 30 wells have been drilled to granite in this 

 State. The results have shown a very peculiar geological phenomenon, 

 namely, the presence of a buried granite ridge, now known to extend 

 from somewhere near the mouth of Platte Eiver, in southeastern Ne- 

 braska, entirely across the State of Kansas and into northern Oklahoma, 

 a distance of over 200 miles. Prof. E. C. Moore, who is our best au- 

 thority on the subject, has very fully discussed the matter in two publi- 

 cations, one in the bulletin of the Geological Survey of Kansas^ ^ and the 

 other a paper read before this Society.^^ He has named this subsurface 

 ridge the Nemaha Mountains. Professor Moore states that at a point 

 near the Kansas-Nebraska line "the crystalline rocks approach to within 

 550 feet of the surface and attain an elevation of nearly 600 feet above 

 sea level '^ The elevation of the crest of the buried ridge gradually de- 

 clines toward the south, granite being encountered at 3,420 feet some 25 

 miles north of the Oklahoma line and at 4,800 feet near Newkirk, Okla- 

 homa. In addition to the writings by Moore, there has already grown up 

 quite a literature on the granite ridge, particularly the writings of 

 Haworth,^^ Taylor,^^ Powers,-^ and Wright.^^ 



Studies made by different geologists of the records of wells which 

 touched crystalline rocks have shown some very interesting facts. While 

 the data are still far from complete, enough facts are now available to 

 postulate the presence of several gra,nite ridges on the plains other than 

 the Nemaha Mountains, already discussed. 



AMARILLO MOUXTAIXS 



In 1905 the writer discovered along the Canadian Eiver, in the north- 

 ern part of the Panhandle of Texas, a series of large structures. These 

 were duly embalmed in the literature and straightway forgotten.-^ In 



