HE CSLO CARBONIFEROUS GLACIAL DEPOSITS 
OF SOUTH AMERICA 
A. P. COLEMAN 
University of Toronto 
INTRODUCTION 
The proofs of tremendous glaciation at the end of the Carbon- 
iferous have been given in great detail from South Africa and Aus- 
tralia and less fully from India; but comparatively little has been 
reported regarding Permo-Carboniferous glaciation in South 
America. Having seen something of the tillites and glaciated rock 
surfaces of typical localities in the first three regions, it seemed 
desirable to visit the less-known glacial deposits of South America. 
During the past summer this has been accomplished, and it is 
proposed to give in this paper a brief account of what was observed. 
The probability that certain Carboniferous or Permian bowlder 
conglomerates with a matrix of shale in southern Brazil were of 
glacial origin was recognized by Orville Derby as early as 1888;7 but 
no striated stones were found, and the evidence seemed scarcely suf- 
ficient to establish the point. In 1907 and 1908 I. C. White and 
David White made it almost certain that the widespread bowlder 
conglomerates were glacial, the latter showing that the accompany- 
ing flora, as collected during I. C. White’s examination of the coal 
deposits of southern Brazil, was identical with floras in a similar 
relation in South Africa and India.? Still the final proof, the finding 
of striated stones, was lacking. 
In 1908 J. B. Woodworth studied the southern Brazilian tillites, 
finding striated stones plentiful and making their glacial origin 
absolutely certain. His report on the field work accomplished, with 
‘Orville Derby, “‘Spuren einer carbonischen Eiszeit in Siid Amerika,’ Newes 
Jahrb. fiir Min., etc., Band II (1888), 175. 
2, David White, ‘‘Permo-Carboniferous Climatic Changes in South America,” 
Jour. Geol., XV (1907), 615-33; and I. C. White, in his Relatorio Final on the Brazilian 
Coal Fields, 1908, pp. 11-110. 
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