Stockdale: Stylolites 



13 



GEOLOGIC DISTRIBUTION OF STYLOLITES 



Stylolites are found in several geologic formations thruout 

 different parts of the world. In Europe their most extensive 

 development is probably to be found in the Muschelkalk (Tri- 

 assic)- of Germany. In America their occurrence is espe- 

 cially noticeable in the Mississippian limestones of Indiana, 

 the Niagaran limestones-' of New York, and the Ordovician 

 marbles (Holston formation) ^ of Tennessee. Their presence, 

 however, is by no means limited to the above-mentioned 

 geologic strata. The Indiana limestones offer examples of 

 the largest and best-developed stylolites in America. 



The Muschelkalk of Germany probably presents the most 

 complex stylolitic structures known. The American lime- 

 stones, as a whole, show less complicated stylolites. The 

 Tennessee marbles, however, exhibit many complexities. 



An important conclusion derived from a study of the 

 geologic distribution of stylolites is that they are present only 

 in carbonate rocks — varieties of limestones, dolomites, and 

 marbles. Their occurrence has not been observed (1) in 

 clastic rocks — conglomerates, sandstones, and shales (with 

 the possible exception of highly calcareous sandstones and 

 shales, in which the percentage of soluble carbonates is ex- 

 tremely high) ; (2) in igneous rocks; (3) or in metamorphic 

 rocks other than carbonate types. 



EARLIEST OBSERVATIONS OF STYLOLITES AND 

 TERMS APPLIED TO THEM 



The earliest mention of stylolites appears to have been 

 made by Mylius, in 1751, who described them as ''Schwielen" 

 and spoke of them as resembling 'Versteinert Holz". Freies- 

 leben, in 1807, spoke of the phenomenon as ''zapfenformige 

 Struktur der Flozkalksteine", and Hausmann later referred 

 to it as ''Stangelkalk". 



- The most extensive parer treating of the stylolites of the Muschelkalk is that of 

 Wag-ner (1913, pp. 101-128). Other late writers are Fuchs (1894, pp. 673-688), Giimbel 

 (1882, p. 642; 1888, p. 187), Reis (1901, pp. 62-92; 1902, p. 157), Rothpletz (1900, 

 pp. Sf-32). 



^ A detailed discussion of the stylolites of American geologic formations has never 

 been written. Earliest observations were made in the Niagaran limestones of New 

 York. They have been described by Eaton (1824, p. 134), Bonnycastle (1831, p. 74). 

 Vanuxem (1838, p. 271; 1842, pp. 107-109), Emmons (1842. p. Ill), Hall (1843. pp. 95, 

 96, 130, 131), Marsh (1867. pp. 135-143). 



The most recent paper upon the stylolites of the Tennessee mai bles is that of 

 Gordon (1918, pp. 561-569). This discussion is very brief and not detailed. 



