Stylolites: Their Nature and Orijj^in 



A Study with Special Reference to Their Occurrence in 

 Indiana Limestones 



By Paris B. Stockdale, Imtructor in Geology, Ohio State 



University 



Part I. Introduction 



There are few of the minor, yet important, geologic phe- 

 nomena whose explanation has been as unsatisfactory and 

 under as much controversy as that of stylolites. They have 

 been observed and described since the middle of the eighteenth 

 century ; yet today their manner of origin is held in doubt by 

 many scientists. 



GENERAL CHARACTERISTICS OF STYLOLITES 



Stylolites consist of a series of alternating, interpenetrat- 

 ing columns of stone which form an irregular, interlocked 

 parting or suture in rock strata (see Figs. 1, 2, 3, and 15). 

 In their most common occurrence they are found along the 

 bedding or lamination planes of limestone, resulting in an 

 intricate interteething of the rock by the alternating do^^^l- 

 ward and upward projection of the columns of one layer into 

 the opposite. The length of these columns varies from a 

 small fraction of an inch to a foot or more. The width is 

 as variable as the length. Oftentimes the union of the stone 

 at a stylolite-parting is so firm that the rock will split more 

 readily elsewhere than along this jagged suture. Where this 

 parting is cut across, as in the wall of a quarry, it presents 

 a rough, jagged line (see Figs. 3, 15, and 26) . To such a 

 line the terms ''stj^lolite-seam" or ''stylolite-line" may well 

 be given. Because of the intricate interlocking of the col- 

 umns, these lines have been compared by Vanuxem (1838, 

 p. 271)^ to the sutures of the human skull (see Fig. 16). 



^ Reference to literature will be made by .uivincc the name of the writer, date of 

 publication, and page. The title of the paper and name of the publication can be 

 obtained by consulting the bibliography. 



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