June 17th, 1914 
Canada 
Geological Survey 
Museum Bulletin No. 2. 
GEOLOGICAL SERIES, No. 14 
II. — Columnar Structure in Limestone. 
By E. M. Kindle. 
Columnar structure, though very rare in sedimentary beds, 
is not altogether unknown in argillaceous sediments . 1 In 
limestones only one example of this structure has ever come 
under the writer’s notice 2 . This occurs in a bed of Silurian 
limestone on Temiscouata lake in eastern Quebec. This structure 
is believed to be here a consequent of special conditions of 
sedimentation. So much remains to be learned about the 
factors of sedimentation involved in the formation of the various 
types of limestone that any deductions or inferences regarding 
them which may be made from physical features merit con- 
sideration as well as the structures themselves. 
The pronounced columnar structure of the limestone shown in 
Plate II is comparable with that found in basalt, but the columns 
are perhaps less regular in the number and width of the sides. 
The columns vary rather widely in the number of f aces shown, 
five to seven being a common number. One side of a column 
may have a width two or three times that of an adjacent side. 
The faces or sides while roughly plane show more or less irregular- 
ity of surface. The columnar limestone is a dark blue, hard, fine 
textured rock. It leaves a fine argillaceous and siliceous residue 
when dissolved in acid. The rock shows on a weathered surface 
Salisbury, R. D., Columnar structure in subaqueous clay, Science, new ser., 
vol. 5, 1885, p. 287. 
2 The structure called stylolites which Is sometimes referred to as columnar 
structure 7 (Geology of Canada, 1863, pp. 631-633) is unrelated to that under 
consideration here. 
56815—3 
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