BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA 

 VOL. 27, PP. 437-450, PL. 18 JUNE 17, 1916 



CRYSTALLINE MABBLES OF ALABAMA 1 



BY WILLIAM F. PROUTY 



{Presented before the Society by title only December 29, 1915) 



CONTENTS 



Page 



Varieties of marble other than crystalline in the State 437 



The crystalline marble 438 



General extent and location 438 



General geologic and topographic setting and age. . . " 438 



Structural conditions 440 



Faulting 440 



Dip 440 



Schistosity 440 



Joints 441 



Drag-folding 443 



Cross-sections of field 44(5 



Relation of calcite and dolomite 447 



Characteristics of the marble 447 



Quarry methods 448 



Mapping the marble 450 



Varieties of Marble other than crystalline in the State 



There are several varieties of marble in the State of Alabama, both 

 crystalline and semi-crystalline. The chief semi-crystalline marbles com- 

 prise the variegated and somewhat brecciated deposits of Middle Cambrian 

 age in Shelby County, near Calera ; 2 the gray and somewhat variegated 

 marble, chiefly of Pelham age, at Pratts Ferry, Bibb County, 3 and the 

 local deposits of marbelized Subcarboniferous and Knox limestones in 

 the northern part of the State. Of these the Pratts Ferry deposit alone 

 has been in the past considerably developed. 



1 Published with the permission of the Alabama Geological Survey. 

 Manuscript received by the Secretary of the Society April 7, 1916. 



2 Henry McCalley : The valley regions of Alabama, vol. ii, pp. 513-514. 

 ■ Charles Butts : Bull. TJ. S. Geological Survey, No. 470, pp. 237-239. 



3 Henry McCalley : The valley regions of Alabama, vol. ii, pp. 498-499. 



P. Byrne : Marble formations of the Cahaba River in Alabama. Trans. Engineering 

 Association of the South, vol. xii, pp. 48-59. 



(437) 



